1.6D Fiesta bike build

[Tetronator]

Lots of compressor troubles it looks like... I bought mine for about 140 Euro's at the local Aldi...
I haven't given it any real hard work but it sure beats manual filling of flat tires or seating tires.



Loud as heck tough and takes a good long time to fill up.


Edit; Maybe couple some of these smaller cheaper units together? Just an idea.

[dieseltech]

Nah. In fact, there's your problem.

One thing which was very apparent from dissecting the failed unit - these cheap compressors are not built for any type of serious use, and definitely built to a price point. The motors use very thin magnet wire, way too thin to handle the amps on a continuous basis.

I'd say that, as a rule of thumb, you can get away with maybe about 25% duty cycle on those units (over a 20-30 minute period). 50% is pushing it really hard. 100% duty, and the motor won't last an hour.

In any case, because they lack an aftercooler, running them for more than about 10 minutes continuously will result in a lot of liquid water in the receiver, and the air hose - unless you live in an extremely arid climate. In any case, not good at all.

For low-duty, occasional DIY use - inflating tires, sporadic blow gun operation, a bit of impact wrenching maybe - these El Cheapo units are generally pretty reasonable (but see note below(*)).

As far as serious work goes, however - sandblasting and the like - forget about it, unless you have really deep pockets - to afford replacing the compressor (or at least the motor) on a regular basis. But then you might just as well buy a real industrial compressor and be done with it, so why even bother?

(*): Beware of substandard welding on the compressor tanks. On cheap compressors, the tanks are NOT certified by a recognized certifying body (ie. ASME(?) in the USA), and NOT built nor tested to any sane margin of safety.
In fact, the vast majority of them wouldn't have a snowball's chance in hell of actually being certified, if they were submitted for certification in the first place.


Regarding duty cycles - interestingly, even the "industrial" belt-drive piston compressors are usually not rated for continuous duty.
I've been browsing the Fini compressor catalog, and they have a compressor sizing chart. For the 8-6 bar range:
Screw compressors, 95-100% max. duty,
Belt drive, two stage - 75% max duty,
All single stage - 60-65% max duty.

And remember, this is NOT your average Chinese crap, but quality compressors manufactured by a reputable company.


@tetronator - going back to your suggestion, hooking up multiple small cheap compressors in parallel would do nothing to address the basic issues of poor quality and lack of basic safety.
And in my case, it would also immediately trip the main breaker if I tried to run more than 1 compressor at a time.

Also, remember that I need my compressor also for sandblasting and painting, which requires dry (and for the latter, also very clean) air. Hence why I attempted to retrofit my old compressor with an aftercooler and the relevant filters, only to discover it dead on arrival.


In the relatively distant past, there have been a few instances of me (or my parents) buying cheap Chinese tools. Mostly because of the difficult financial situation back then.
The majority of that crap eventually ended up where it rightfully belongs: in the garbage bin. Which then generally involved buying a replacement tool of proper quality.

Just look at this particular instance:
- cheap crappy compressor, ~$200-250 a few years ago (now correct that for inflation!),
- all the time, effort, and resources wasted on attempting to upgrade it, ~$400+, or much more, depending on how you count,
- a new, quality compressor, ~$500+, and possibly much MUCH more.
End result, ~$600+ down the drain. Gone forever. And totally avoidable, if I had bought a REAL industrial compressor in the first place.
Not to mention all the grief the whole situation caused me.

And this anti-pattern is the same with most other tools - be it wrenches, sockets, ratchets, drills, angle grinders, kitchen tools, whatever, you name it.

***************************

In any case, I've done some thinking concerning selecting a new compressor, and I'm strongly inclined to get an industrial quality 100L (or maybe 150L), 10 bar, belt driven, single phase compressor. Manufactured by a reputable company, not some Wan Hung Lo chinese crap.
Preferably 2.2kW, but 1.5kW will have to do if 2.2kW is not available. Still way too little power for my needs, but at least with the bigger tank, and the higher cut-in pressure (due to the 10bar rating), it should be a bit more manageable.
The next order of business is to measure the available space in my car. No point buying a compressor that I can't load into the car (trailers are out of the question - I don't have neither a trailer, nor a tow hook). A 100L compressor should just about fit, 150L might be too large though.

And then I'll take the filters and aftercooler+fans - which were intended for the previous P.O.S. compressor - and install them on the new one, with an extra input port for connecting an optional external compressor, so that the external air would also pass through the cooler and filters.
That way, in the future (once I have my own workshop set up) I can hook up a big 4+kW 3-phase compressor as well, greatly increasing the available throughput for peak demand situations, while still getting the full benefit of the rather expensive filters installed on the single-phase compressor.

[Tetronator]

@tetronator - going back to your suggestion, hooking up multiple small cheap compressors in parallel would do nothing to address the basic issues of poor quality and lack of basic safety.
And in my case, it would also immediately trip the main breaker if I tried to run more than 1 compressor at a time.

Also, remember that I need my compressor also for sandblasting and painting, which requires dry (and for the latter, also very clean) air. Hence why I attempted to retrofit my old compressor with an aftercooler and the relevant filters, only to discover it dead on arrival.

Well, that idea sure got blown out of the sky. (Get it? Blown out of the sky. )
But hey, I am by no means an expert on the subject...

(*): Beware of substandard welding on the compressor tanks. On cheap compressors, the tanks are NOT certified by a recognized certifying body (ie. ASME(?) in the USA), and NOT built nor tested to any sane margin of safety.
In fact, the vast majority of them wouldn't have a snowball's chance in hell of actually being certified, if they were submitted for certification in the first place.

To my untrained eye the welds on my units tank look OK, not pretty but OK. Nevertheless, once I am done with it, I completely depressurize it every time to be sure.

Manufactured by a reputable company, not some Wan Hung Lo chinese crap.

I see you concerns and I do agree with not buying anything Chinese if you can help it. (Thats why I don't want a winsun or punsun in my bike).

Maybe source some parts from old 'good' compressors and build your own?

[bf109v7]

To my untrained eye the welds on my units tank look OK, not pretty but OK. Nevertheless, once I am done with it, I completely depressurize it every time to be sure.

It is very easy to test it yourself. Fill the Tank with water and then pump it up to 1,5 times the pressure it should take. If it blows up you have a little bang from the air you put in for the pressure an midium sise flood.
Alex

[bf109v7]

To my untrained eye the welds on my units tank look OK, not pretty but OK. Nevertheless, once I am done with it, I completely depressurize it every time to be sure.

It is very easy to test it yourself. Fill the Tank with water and then pump it up to 1,5 times the pressure it should take. If it blows up you have a little bang from the air you put in for the pressure an midium sise flood.
Alex

[Tetronator]

To my untrained eye the welds on my units tank look OK, not pretty but OK. Nevertheless, once I am done with it, I completely depressurize it every time to be sure.

It is very easy to test it yourself. Fill the Tank with water and then pump it up to 1,5 times the pressure it should take. If it blows up you have a little bang from the air you put in for the pressure an midium sise flood.
Alex

That is actually pretty smart, but I also do not posses copious amounts of money to trow at it. It does still have warranty tough...

[bf109v7]

You don't have to expect that it will blow. I testetet about 55 Tanks this way, not one blew. I dont know how close you are when it is presurerised with air, but it can kill you if it blows. But, on the other hand, if it still have Warranty, I would not worry to much.
Alex

[dieseltech]

To my untrained eye the welds on my units tank look OK, not pretty but OK. Nevertheless, once I am done with it, I completely depressurize it every time to be sure.

Any visible undercut on the welds is a serious cause for concern. Although minor undercut might not be visible through the (relatively thick) paint coating.
Also, keep in mind that with MIG welding (which is how these are made), it is very easy to make a weld that looks beautiful, but is absolutely worthless in terms of structral integrity.

Also, here's what ASME has to say on the subject of pressure vessel design (emphasis mine):
"(...) a pressure of 1.5 times the maximum allowable working pressure should not produce stresses in the vessel that exceed the yield stress of the material. And at 3.5 times that pressure, the stresses should not exceed the ultimate tensile strength."
Here's a link to some interesting reading on the subject.

In other words, according to the above, there should be no permanent deformation after a 50% overpressure, and the tank must not actually explode at 250% (!) overpressure... if it is to receive an ASME certification (or equivalent, in countries other than the USA). Which the imported/rebadged Chinese compressors invariably lack.

Not to mention that the "mystery metal" they're made of can be pretty much any scrap steel they remelted that day. Most likely quite weak and brittle, and NOT suitable for pressure vessel construction.

The bottom line is - the safety of the cheap compressors can't be guaranteed. If you absolutely must use one, it's best to either move it to a safe location before firing it up (ie. outside), or, if that's not possible, then try locating it in a separate room, or at least behind a very sturdy partition of some sort. Either way, it is very unwise to stand near such a compressor when it's pressurized and running.

In my current "temporary" workshop, the old compressor (not mine, the property owner's) is really old, dinged, rusty and nasty, looks like it's about to blow any second now. I reduced the pressure switch and relief valve settings by about 2 bar to improve the "safety" somewhat, and the compressor is hidden away between a concrete wall and a very large pile of steel scaffolding frames.

Maybe source some parts from old 'good' compressors and build your own?

Unfortunately, the tanks on compressors do deteriorate significantly with age. Mostly due to internal corrosion at the bottom, especially if they aren't regularly drained. Which, unfortunately, tends to be the rule, rather than the exception. I've personally seen tanks over half full of water (!) on very neglected units - does that officially make it a water tank then?
All in all, it probably isn't worth the risk. And it's definitely not worth the amount of time, money and effort involved, anyway.


Regarding my initial idea of building a diesel compressor - It sounds great, but... there are 3 main problems with that.
One is portability, or rather the lack thereof.
Another problem is much more trivial. In a one-man workshop, there are always some days when the air usage is very low. Way too low to justify running the diesel all day, in any case. Then what? Go and restart the engine every time the pressure gets too low? Far too much hassle.
Finally, placement. Obviously, running the diesel indoors is out of the question. Permanently placing it outdoors, also out of the question, due to the possibility of theft. Carting the huge and heavy beast in and out of the shop every morning and evening? Meh. Not likely.

So, as it turns out, this is one of the very few instances of a problem where slapping a diesel on it is not a viable long-term solution

*********************

In the end, I've done the measurements: a 90L compressor will just barely fit in my car; the limiting factor is the height. In fact it might be 1-2 cm short of being able to fit through the trunk opening, but I can easily gain that much by changing the compressor's wheels to a smaller size, and/or tilting it sideways a bit during loading/unloading.
The 150L would easily fit as far as the length goes, but it's about 15cm too tall

So it's settled. I'm buying this compressor (from a different, local distributor, of course). ~$600 incl. shipping.
And then I'll install the aftercooler and extra filters on it. Which will void the warranty, but it's not like it really matters after the first few hours of use anyway.

[Tetronator]

You don't have to expect that it will blow. I testetet about 55 Tanks this way, not one blew. I dont know how close you are when it is presurerised with air, but it can kill you if it blows. But, on the other hand, if it still have Warranty, I would not worry to much.
Alex

The bottom line is - the safety of the cheap compressors can't be guaranteed. If you absolutely must use one, it's best to either move it to a safe location before firing it up (ie. outside), or, if that's not possible, then try locating it in a separate room, or at least behind a very sturdy partition of some sort. Either way, it is very unwise to stand near such a compressor when it's pressurized and running.

Right next to it. So if it goes I'm in trouble for sure. All this talk has made me think of putting it in its own little protective box tough, see about that in the new house.
But I like being able to walk around a car with it and just inflate all the tires, I only pump it up to about 5 bars then.

Any visible undercut on the welds is a serious cause for concern. Although minor undercut might not be visible through the (relatively thick) paint coating.
Also, keep in mind that with MIG welding (which is how these are made), it is very easy to make a weld that looks beautiful, but is absolutely worthless in terms of structral integrity.

'The machine's specs

Most welds look like this. To me, this looks good.

Regarding my initial idea of building a diesel compressor - It sounds great, but... there are 3 main problems with that.
One is portability, or rather the lack thereof.
Another problem is much more trivial. In a one-man workshop, there are always some days when the air usage is very low. Way too low to justify running the diesel all day, in any case. Then what? Go and restart the engine every time the pressure gets too low? Far too much hassle.
Finally, placement. Obviously, running the diesel indoors is out of the question. Permanently placing it outdoors, also out of the question, due to the possibility of theft. Carting the huge and heavy beast in and out of the shop every morning and evening? Meh. Not likely.

So, as it turns out, this is one of the very few instances of a problem where slapping a diesel on it is not a viable long-term solution

Maybe add 2 pumps? One diesel and one electric less powerful for the low use days.

Just weigh it down with so much weight no one wants to go to the hassle of stealing it.
Also, rust coat. (Works for Amsterdam bicycles so why not compressors?)

In the end, I've done the measurements: a 90L compressor will just barely fit in my car; the limiting factor is the height. In fact it might be 1-2 cm short of being able to fit through the trunk opening, but I can easily gain that much by changing the compressor's wheels to a smaller size, and/or tilting it sideways a bit during loading/unloading.
The 150L would easily fit as far as the length goes, but it's about 15cm too tall

So it's settled. I'm buying this compressor (from a different, local distributor, of course). ~$600 incl. shipping.
And then I'll install the aftercooler and extra filters on it. Which will void the warranty, but it's not like it really matters after the first few hours of use anyway.

That... looks like a serious compressor. Reminds me of one 100 Year old compressor I saw being used in an engine museum...

...To start the old ship diesels.
It was the best.

https://youtu.be/8qZ413p9M20?t=45s

[UAofE]

Finally, placement. Obviously, running the diesel indoors is out of the question.

No different with a gasoline engine.

[dieseltech]

The machine's specs

Aha, rated at 25% duty cycle... which effectively means VERY light duty.

3400rpm @50Hz? Definitely NOT physically possible with an induction motor. Either it uses a universal motor - rather unlikely at such a "low" RPM range though - or the sticker is outright lying (guess which is more likely...)
3000rpm is the theoretical upper limit for induction motors @50Hz. In practice it's about 2600-2800rpm under load, due to electromagnetic slip. 3200-3400rpm would be about right @60Hz.

Also, duct taped already?

Most welds look like this. To me, this looks good.

On my old chinese unit, most welds also look like that. Except for that one heavily undercut bugger, right at the carrying handle - a highly stressed point, due to the long lever arm afforded by the handle, combined with its heavy vibration due to a mechanical resonance.
It's also in a very difficult welding position, due to the highly acute angle involved (poor design), so no wonder they couldn't get the welding right on that one.
The bead in your photo, if it is 100+% penetration (there's no easy way of checking, unfortunately), looks... passable.

Just weigh it down with so much weight no one wants to go to the hassle of stealing it.
Also, rust coat. (Works for Amsterdam bicycles so why not compressors?)

Nah, that's not how thieves work. Not around here, at least.
If it's valuable, and isn't very permanently attached to the ground (bedrock, preferably), it's quite likely to get stolen eventually. And even if it's very permanently attached, then the detachable bits will be stolen instead. For scrap metal, if not for use/resale value.
A friend of mine once had an old, failed central heating furnace stolen from his own front yard at night, while he was sleeping in the house. It was due to be scrapped the next day - he had just removed it from the basement in the afternoon. Woke up in the early morning, nope, no sign of the furnace. And mind you, that's a big hunk of junk. A few hundred kilos at least. Which, incidentally, means at least a whole crate of cheap wine bottles at the scrapyard...

Maybe add 2 pumps? One diesel and one electric less powerful for the low use days.

For now I should be able to scrape by with this new single-phase unit. And then, further increasing the compressed air supply becomes a very low-priority issue. Eventually, in the far future, I'd prefer to supplement it with a 270L, 5.5-7.5kW, 2-stage 3-phase compressor, to handle the peak loads. Even just the extra tank capacity would help quite a bit.

As of right now, the situation doesn't really merit investing in a diesel compressor, in any case.

When I can eventually afford to build my own house+workshop, I'll most certainly go big on the electricity. We're talking 3-phase of course, and at least a 32A distribution (main) breaker.
That's good to about 20kW - much more than strictly necessary power-wise, but absolutely needed due to the preponderance of high-power single-phase loads, which cause a heavy phase loading imbalance under realistic operating conditions.

[rant]
Incidentally, in Poland at least, there's no extra per-month payment incurred for having a ludicrously large breaker rating. The tariff monthly rates are all the same, whether you have an eg. 10A or a 32A distribution breaker installed. It only affects the initial installation costs, to the tune of a few tens of $ per extra kW of load capacity. Which is why it's better to go big right from the start - in the long term, it's vastly cheaper than upgrading (read: replacing) the whole installation X years later on.

There are basically 2 unwritten rules pertaining to sizing distribution breakers, true in most everyday-life instances:
1. However much power you already have available, it will not be enough. If not right away, then usually in a few years.
2. No matter how much (or little) power you think you will need, it will be actually much more than that.
[/rant]

Finally, placement. Obviously, running the diesel indoors is out of the question.

No different with a gasoline engine.

I was making a general point here, about running engines inside what is effectively a relatively small, and closed, room.

Also, it is different with a gasoline engine:
A properly maintained diesel is fairly safe to operate in sufficiently large (but still enclosed) spaces, due to the very low carbon monoxide output. I've even seen diesel vehicles being operated in the cramped tunnels of underground mines. Not to mention all the diesel forklifts being operated every day inside of factories and warehouses.
OTOH, a carburated, uncatalyzed gasser - ie. your typical "small engine" - will spew out a few percent of CO... on a good day. Much more if the carb is out of adjustment, or the air filter is clogged, etc. IIRC, a small fraction of a % of CO in the air will kill you dead. You can draw your own conclusions from that.

[Tetronator]

The machine's specs

Aha, rated at 25% duty cycle... which effectively means VERY light duty.

3400rpm @50Hz? Definitely NOT physically possible with an induction motor. Either it uses a universal motor - rather unlikely at such a "low" RPM range though - or the sticker is outright lying (guess which is more likely...)
3000rpm is the theoretical upper limit for induction motors @50Hz. In practice it's about 2600-2800rpm under load, due to electromagnetic slip. 3200-3400rpm would be about right @60Hz.

Well, it was pretty cheap, wasn't expecting miracles. Quality costs money after-all.

Also, duct taped already?

https://www.youtube.com/watch?v=J2l-F1ElJMc

Nah, that's just to hold on an accessory to stop it from rattling off somewhere. (So yeah, duct tape already. )

Most welds look like this. To me, this looks good.

On my old chinese unit, most welds also look like that. Except for that one heavily undercut bugger, right at the carrying handle - a highly stressed point, due to the long lever arm afforded by the handle, combined with its heavy vibration due to a mechanical resonance.
It's also in a very difficult welding position, due to the highly acute angle involved (poor design), so no wonder they couldn't get the welding right on that one.
The bead in your photo, if it is 100+% penetration (there's no easy way of checking, unfortunately), looks... passable.

Welp, better take some precautions then next time I use it.

Just weigh it down with so much weight no one wants to go to the hassle of stealing it.
Also, rust coat. (Works for Amsterdam bicycles so why not compressors?)

Nah, that's not how thieves work. Not around here, at least.
If it's valuable, and isn't very permanently attached to the ground (bedrock, preferably), it's quite likely to get stolen eventually. And even if it's very permanently attached, then the detachable bits will be stolen instead. For scrap metal, if not for use/resale value.
A friend of mine once had an old, failed central heating furnace stolen from his own front yard at night, while he was sleeping in the house. It was due to be scrapped the next day - he had just removed it from the basement in the afternoon. Woke up in the early morning, nope, no sign of the furnace. And mind you, that's a big hunk of junk. A few hundred kilos at least. Which, incidentally, means at least a whole crate of cheap wine bottles at the scrapyard...

Sounds like my current neighborhood! All-tough here they also do it to buy more weed at the coffeeshops. They're creative enough to steal the copper wires away from above the train tracks. (Those things are live at 1500 Volts.)
I get why you cant leave ANYTHING outside then, sadly enough.

Maybe add 2 pumps? One diesel and one electric less powerful for the low use days.

For now I should be able to scrape by with this new single-phase unit. And then, further increasing the compressed air supply becomes a very low-priority issue. Eventually, in the far future, I'd prefer to supplement it with a 270L, 5.5-7.5kW, 2-stage 3-phase compressor, to handle the peak loads. Even just the extra tank capacity would help quite a bit.

As of right now, the situation doesn't really merit investing in a diesel compressor, in any case.

When I can eventually afford to build my own house+workshop, I'll most certainly go big on the electricity. We're talking 3-phase of course, and at least a 32A distribution (main) breaker.
That's good to about 20kW - much more than strictly necessary power-wise, but absolutely needed due to the preponderance of high-power single-phase loads, which cause a heavy phase loading imbalance under realistic operating conditions.

That sounds awesome!

[rant]
Incidentally, in Poland at least, there's no extra per-month payment incurred for having a ludicrously large breaker rating. The tariff monthly rates are all the same, whether you have an eg. 10A or a 32A distribution breaker installed. It only affects the initial installation costs, to the tune of a few tens of $ per extra kW of load capacity. Which is why it's better to go big right from the start - in the long term, it's vastly cheaper than upgrading (read: replacing) the whole installation X years later on.

There are basically 2 unwritten rules pertaining to sizing distribution breakers, true in most everyday-life instances:
1. However much power you already have available, it will not be enough. If not right away, then usually in a few years.
2. No matter how much (or little) power you think you will need, it will be actually much more than that.
[/rant]

Go big or go home, huh?

[dieseltech]

Sounds like my current neighborhood! All-tough here they also do it to buy more weed at the coffeeshops. They're creative enough to steal the copper wires away from above the train tracks. (Those things are live at 1500 Volts.)

Happens all the time in Poland (the stealing, not the legal weed, unfortunately ).
BTW, In Poland, it's 2.5kV DC, IIRC - not that it matters much, since it'll kill you dead in any case, especially since many megawatts of power are routinely available.

All that theft does not help our dying railway infrastructure in the slightest, especially since the vast majority of track is electrified - the diesels are used mostly for shunting yard duty, and to service the small minority of unelectrified track - mostly consisting of stub lines to large factories, etc.
Until fairly recently, it was also very common to hear about stolen rails, manhole covers, and roadside drainage grates. Luckily, these days most scrapyards refuse to accept ony of those 3, and IIRC they have a duty to report that to the police, too. So the thefts of those have mostly stopped.

And the thieves can range from extremely dumb (Darwin Awards, anyone?) - ie. trying to steal copper bus bars from the roof of an electric loco... with the pantographs still raised (result = carbonized husk of a thief found in the morning) - to extremely clever:
Sometime in the last few years, there was a major derailment in Poland, caused by stolen rail. Which is unusual, because the main lines are protected by track circuits, which, in addition to detecting the presence/absence of trains, can also detect broken/missing rails (the protected section then shows up as permanently occupied, blocking the trains from progressing any further).

So what happened? The thieves stole a large length of a single rail, bridging the gap with a length of wire (no doubt also stolen from somewhere!).
Why only one of the rails? Because the other is needed to carry the traction current - which can easily reach a few thousand amps on lines with heavy traffic.
And by bridging the missing length of rail with a length of wire, they defeated the protection afforded by the track circuit, so that nothing seemed out of the ordinary.

I dare say that the only way to top that would be to somehow steal the rails while a train is rolling on them, although I have no idea how such a feat might even be accomplished.

Go big or go home, huh?

That's how it is, really.
Think about it: right now I'm living in a flat of several square meters. 2 rooms + kitchen + bathroom + corridor. So, if we compare it to a typical freestanding house, it's positively tiny.
Yet, if I wanted to upgrade the wiring for any reason, or install 3-phase power (say, if I wanted an induction cooktop or somesuch), the amount of cost and effort involved would be colossal.

It would require moving ALL the furniture to get access to the walls. Note that some of the furniture is several years old, EXTREMELY large and heavy, and designed to never be moved at all.
Then a lot of demolition work would be necessary to gain access to the old wires, some of which are located in areas which make them positively impossible to remove without risking a major structural failure of the building itself.
Then it'd be necessary to repair the major damage incurred to the walls and ceilings, including re-wallpapering/repainting/retiling them.
And finally, move ALLthe furniture back into place.

All in all, at least 2-3 weeks of backbreaking labor... if you had a few people to help out. So we're talking about a few hundred man-hours, at the very least. Plus the cost of new wiring, cement, plaster, paint, wallpaper, tiles etc...

Absolutely not worth it. IMO it's one of those cases where it's far better to spend the extra money up front, and be set up for pretty much the rest of your life, rather than try to save a few $$$, and end up being royally screwed a couple years down the road.


****************************************

Going back to the subject of my build, I've made some progress on the connecting rods yesterday.
First, I jury-rigged a suitable jig for accurately and repeatably weighing the connecting rod ends. Luckily, I had all the needed hardware lying around, so it only took a couple of minutes.
Then, I ran some tests to see how good the jig was. And the answer is... very good.

Taking the same rod off, and putting it back on the jig, the measurements were all within +/- 0.1g.
If I was careful to also center the rod laterally on the bearings, the readings were within +/- 0.05g most of the time.
Not bad at all, considering that the jig was built mostly out of random crap lying around the workshop, and that it was positioned on a very flimsy, wobbly table.

In fact, if just placed the other 3 conrods on the table beside the jig, it would throw off the readings by well over a gram, due to the table surface sagging further under the extra load.

Here are a few photos (click to enlarge):



(note to self: do NOT trust the automatic white balance)
Also, for some bizarre reason the photos are overexposed, even though the camera was clearly set up to measure the light level averaged over the entire shot, not just in the center.

Anyway, here you can see the jig in action. That rod has had about 1/2 of the needed material removed, at the time that photo was taken.
If you're wondering why I didn't remove material from the obvious area on the cap first - that's because I separately balanced all the caps+screws first, before tackling the whole rods.
So no grinding the caps anymore at this point.

Also, balancing the big ends of forged rods by grinding only the caps is an inferior method, since it makes the mass unevenly distributed.
And that does make a difference, because of how it moves during operation.

As it turns out, the heaviest rods had the lightest caps, and vice-versa. No surprise there, really, since that's how it was done in the engine factories back in their day.
Because the rods and caps are forged, there will naturally be significant variation in their mass and its distribution.
The heaviest rod is ~0.2-0.5mm thicker (in the as-forged, unmachined areas) than the lightest one.

Finally, in case you're wondering... no, there is no harm in removing material from the rod in such a way. Remember, it is thicker than the lightest rod to begin with. Also, the rods were massively over-designed anyway - especially compared to modern designs.
Also, in fact, there is a net benefit to (lightly!) grinding a rod in this way: the smoother surface means fewer (and smaller) stress risers, which reduces the likelihood of developing cracks, despite the slight decrease in overall cross-section.


And now, a view from a few other angles:








Unfortunately, I was unable to finish balancing the rods yesterday. In fact, I ran out of time before I was able to balance even one rod, since I had other things to take care of before this, and when I began I only had 1-2 hours left.

So, for now, this was more of a proof-of-concept, really. But - in the end - it did, in fact, prove the viability of this approach.

Now, if all goes well, I might be able to finish balancing all 4 rods next Saturday.

[Tetronator]

Sounds like my current neighborhood! All-tough here they also do it to buy more weed at the coffeeshops. They're creative enough to steal the copper wires away from above the train tracks. (Those things are live at 1500 Volts.)

Happens all the time in Poland (the stealing, not the legal weed, unfortunately ).
BTW, In Poland, it's 2.5kV DC, IIRC - not that it matters much, since it'll kill you dead in any case, especially since many megawatts of power are routinely available.

All that theft does not help our dying railway infrastructure in the slightest, especially since the vast majority of track is electrified - the diesels are used mostly for shunting yard duty, and to service the small minority of unelectrified track - mostly consisting of stub lines to large factories, etc.
Until fairly recently, it was also very common to hear about stolen rails, manhole covers, and roadside drainage grates. Luckily, these days most scrapyards refuse to accept ony of those 3, and IIRC they have a duty to report that to the police, too. So the thefts of those have mostly stopped.

And the thieves can range from extremely dumb (Darwin Awards, anyone?) - ie. trying to steal copper bus bars from the roof of an electric loco... with the pantographs still raised (result = carbonized husk of a thief found in the morning) - to extremely clever:
Sometime in the last few years, there was a major derailment in Poland, caused by stolen rail. Which is unusual, because the main lines are protected by track circuits, which, in addition to detecting the presence/absence of trains, can also detect broken/missing rails (the protected section then shows up as permanently occupied, blocking the trains from progressing any further).

So what happened? The thieves stole a large length of a single rail, bridging the gap with a length of wire (no doubt also stolen from somewhere!).
Why only one of the rails? Because the other is needed to carry the traction current - which can easily reach a few thousand amps on lines with heavy traffic.
And by bridging the missing length of rail with a length of wire, they defeated the protection afforded by the track circuit, so that nothing seemed out of the ordinary.

I dare say that the only way to top that would be to somehow steal the rails while a train is rolling on them, although I have no idea how such a feat might even be accomplished.

Pfft, challenge accepted.

Impressive tough, the thieves here have yet to try and steal railroad tracks.

Go big or go home, huh?

That's how it is, really.
Think about it: right now I'm living in a flat of several square meters. 2 rooms + kitchen + bathroom + corridor. So, if we compare it to a typical freestanding house, it's positively tiny.
Yet, if I wanted to upgrade the wiring for any reason, or install 3-phase power (say, if I wanted an induction cooktop or somesuch), the amount of cost and effort involved would be colossal.

It would require moving ALL the furniture to get access to the walls. Note that some of the furniture is several years old, EXTREMELY large and heavy, and designed to never be moved at all.
Then a lot of demolition work would be necessary to gain access to the old wires, some of which are located in areas which make them positively impossible to remove without risking a major structural failure of the building itself.
Then it'd be necessary to repair the major damage incurred to the walls and ceilings, including re-wallpapering/repainting/retiling them.
And finally, move ALLthe furniture back into place.

All in all, at least 2-3 weeks of backbreaking labor... if you had a few people to help out. So we're talking about a few hundred man-hours, at the very least. Plus the cost of new wiring, cement, plaster, paint, wallpaper, tiles etc...

Absolutely not worth it. IMO it's one of those cases where it's far better to spend the extra money up front, and be set up for pretty much the rest of your life, rather than try to save a few $$$, and end up being royally screwed a couple years down the road.

You actually considered building a workshop inside an apartment? That would be a sight to behold.
But yeah I'm in the middle of moving now myself. Then I've finally got a place to start my build!

Going back to the subject of my build, I've made some progress on the connecting rods yesterday.
First, I jury-rigged a suitable jig for accurately and repeatably weighing the connecting rod ends. Luckily, I had all the needed hardware lying around, so it only took a couple of minutes.
Then, I ran some tests to see how good the jig was. And the answer is... very good.

Taking the same rod off, and putting it back on the jig, the measurements were all within +/- 0.1g.
If I was careful to also center the rod laterally on the bearings, the readings were within +/- 0.05g most of the time.
Not bad at all, considering that the jig was built mostly out of random crap lying around the workshop, and that it was positioned on a very flimsy, wobbly table.

In fact, if just placed the other 3 conrods on the table beside the jig, it would throw off the readings by well over a gram, due to the table surface sagging further under the extra load.

Here are a few photos (click to enlarge):



(note to self: do NOT trust the automatic white balance)
Also, for some bizarre reason the photos are overexposed, even though the camera was clearly set up to measure the light level averaged over the entire shot, not just in the center.

Anyway, here you can see the jig in action. That rod has had about 1/2 of the needed material removed, at the time that photo was taken.
If you're wondering why I didn't remove material from the obvious area on the cap first - that's because I separately balanced all the caps+screws first, before tackling the whole rods.
So no grinding the caps anymore at this point.

Also, balancing the big ends of forged rods by grinding only the caps is an inferior method, since it makes the mass unevenly distributed.
And that does make a difference, because of how it moves during operation.

As it turns out, the heaviest rods had the lightest caps, and vice-versa. No surprise there, really, since that's how it was done in the engine factories back in their day.
Because the rods and caps are forged, there will naturally be significant variation in their mass and its distribution.
The heaviest rod is ~0.2-0.5mm thicker (in the as-forged, unmachined areas) than the lightest one.

Finally, in case you're wondering... no, there is no harm in removing material from the rod in such a way. Remember, it is thicker than the lightest rod to begin with. Also, the rods were massively over-designed anyway - especially compared to modern designs.
Also, in fact, there is a net benefit to (lightly!) grinding a rod in this way: the smoother surface means fewer (and smaller) stress risers, which reduces the likelihood of developing cracks, despite the slight decrease in overall cross-section.


And now, a view from a few other angles:








Unfortunately, I was unable to finish balancing the rods yesterday. In fact, I ran out of time before I was able to balance even one rod, since I had other things to take care of before this, and when I began I only had 1-2 hours left.

So, for now, this was more of a proof-of-concept, really. But - in the end - it did, in fact, prove the viability of this approach.

Now, if all goes well, I might be able to finish balancing all 4 rods next Saturday.

Nice! Ever thought about a job in analytic physics?

I like how your using an analytic scale but you really need to sort the table for a sturdier one,
preferably a granite pillar straight into bedrock but I doubt you've got one of those around.
So the most sturdy one you've got around.

You can also make an air seal box around the entire thing to make it even more accurate.

[dieseltech]

Impressive tough, the thieves here have yet to try and steal railroad tracks.

Probably because they're far less valuable, by an order of magnitude.
OTOH, they're also much easier and "safer" to steal than the traction wiring.

Nice! Ever thought about a job in analytic physics?

No, not really. If college has taught me anything, it was that any laboratory work involves A. LOT. OF. PAPERWORK. Especially anything related to physics.
And not only paperwork of the dumb, mindless type - no, it's the most EVIL kind of paperwork, the kind that involves doing a lot of calculations.

Before you mention it - even if a computer is used to do ALL the calculations, it still requires entering the data, entering the equations, and presenting the results appropriately (ie. graphs, tables, etc.)

I hate paperwork. Maybe it's because of my experiences with college, but every time I have to fill out any paperwork, I feel like I'm completely wasting my time.

Also, I don't like R&D-type jobs - even if you don't screw enything up on your end, the boss/management might not like your idea, etc. There's just too much that can go wrong.
At work, my boss does a lot of the R&D himself, with a small handful of people helping him out with actually converting his "ideas" into "reality".
And if I were to describe the life of those people... "miserable" is the first term that comes to mind. I would definitely not like to be in their place, especially since they don't really earn much more than the rest of us. Certainly not enough to offset their... predicament.

The way I see it, it's not good to have too much of decision-making authority at work (unless you're the boss, of course - good for you, I guess).
When I was just an assembly worker (NOT an assembly line worker!), it was all nice and dandy: make sure you do your job to an appropriate standard of quality, and Bob's your uncle. I only got into trouble very few times - almost invariably because of some lapse of judgment on my part.
Now, in my current situation, it's not quite as nice overall - even though now I work >95% of the time sitting at a table, in my own room, far from the noise and chaos of the assembly hall.

I like how your using an analytic scale but you really need to sort the table for a sturdier one,
preferably a granite pillar straight into bedrock but I doubt you've got one of those around.
So the most sturdy one you've got around.

You can also make an air seal box around the entire thing to make it even more accurate.

I wouldn't exactly call it an analytic scale, really. At ~$120 and 0.01g accuracy, it's much more accurate than the typical kitchen scale - but still 2 orders of magnitude worse than the one you linked to.

Air seal box, not needed at the 0.01g range. Not like it would matter anyway - a drop of oil on the rod surface is a good few 0.01 grams. My rod balancing jig is only repeatable to a similar precision, too.
In fact, a 0.1g scale would've been easily enough for balancing engine parts - at least for engines of this size (for the tiny engines used in RC models, 0.1g imbalance is a lot!).


In any case, even if the parts themselves were perfectly balanced, the engine will still vibrate somewhat - piston motion is nonsinusoidal, so there can never be 100% cancellation of reciprocating inertia. Similarly for the connecting rods, since they're a distributed mass; the 2-mass "dumbbell" approximation used for balancing is just that - an approximation.
Combustion forces cause the engine parts to flex in weird and wonderful ways, and that also causes vibrations.
The valvetrain is simply impossible to balance, ever. Luckily, it is of little importance, since the speeds are relatively low, and the masses and displacements are rather small.

Finally, the torque applied to the crankshaft (and thus, also to the engine block) is nonsteady, with a cylinder firing once for every 1/2 revolution, and at low RPMs this will be the dominant vibration component anyway.
Also, any imbalance in power output between cylinders will manifest as additional vibration.The only viable way to address that, is to calibrate the injector opening pressure to be within tight tolerances of each other.

Well, you could also carefully equalize the compression ratio, piston-cylinder clearance and ring gaps between all cylinders, but that's well beyond the point of diminishing returns.
I'm not saying that it's bad to do so - in fact, it's an essential step for getting the most mileage and best performance possible out of an engine - but the cost involved is enormous, and in this case, the benefits would be insignificant.
The pistons, rings and cylinders will easily last > 200 000 km without any noticeable degradation in the smoothness of running (due to differences in amount of blowby present on different cylinders).
Think about it - that's 5x more than the circumference of the freaking planet, and enough to last me several years of riding - pretty much the rest of my life. So what's the point of bothering with any further "gold plating"?

[Tetronator]

Nice! Ever thought about a job in analytic physics?

No, not really. If college has taught me anything, it was that any laboratory work involves A. LOT. OF. PAPERWORK. Especially anything related to physics.
And not only paperwork of the dumb, mindless type - no, it's the most EVIL kind of paperwork, the kind that involves doing a lot of calculations.

Before you mention it - even if a computer is used to do ALL the calculations, it still requires entering the data, entering the equations, and presenting the results appropriately (ie. graphs, tables, etc.)

I hate paperwork. Maybe it's because of my experiences with college, but every time I have to fill out any paperwork, I feel like I'm completely wasting my time.

Also, I don't like R&D-type jobs - even if you don't screw enything up on your end, the boss/management might not like your idea, etc. There's just too much that can go wrong.
At work, my boss does a lot of the R&D himself, with a small handful of people helping him out with actually converting his "ideas" into "reality".
And if I were to describe the life of those people... "miserable" is the first term that comes to mind. I would definitely not like to be in their place, especially since they don't really earn much more than the rest of us. Certainly not enough to offset their... predicament.

The way I see it, it's not good to have too much of decision-making authority at work (unless you're the boss, of course - good for you, I guess).
When I was just an assembly worker (NOT an assembly line worker!), it was all nice and dandy: make sure you do your job to an appropriate standard of quality, and Bob's your uncle. I only got into trouble very few times - almost invariably because of some lapse of judgment on my part.
Now, in my current situation, it's not quite as nice overall - even though now I work >95% of the time sitting at a table, in my own room, far from the noise and chaos of the assembly hall.

Well you hit the nail on the head there, I myself am an chemical analyst.
Meant it more as a compliment.

I like how your using an analytic scale but you really need to sort the table for a sturdier one,
preferably a granite pillar straight into bedrock but I doubt you've got one of those around.
So the most sturdy one you've got around.

You can also make an air seal box around the entire thing to make it even more accurate.

I wouldn't exactly call it an analytic scale, really. At ~$120 and 0.01g accuracy, it's much more accurate than the typical kitchen scale - but still 2 orders of magnitude worse than the one you linked to.

Air seal box, not needed at the 0.01g range. Not like it would matter anyway - a drop of oil on the rod surface is a good few 0.01 grams. My rod balancing jig is only repeatable to a similar precision, too.
In fact, a 0.1g scale would've been easily enough for balancing engine parts - at least for engines of this size (for the tiny engines used in RC models, 0.1g imbalance is a lot!).


In any case, even if the parts themselves were perfectly balanced, the engine will still vibrate somewhat - piston motion is nonsinusoidal, so there can never be 100% cancellation of reciprocating inertia. Similarly for the connecting rods, since they're a distributed mass; the 2-mass "dumbbell" approximation used for balancing is just that - an approximation.
Combustion forces cause the engine parts to flex in weird and wonderful ways, and that also causes vibrations.
The valvetrain is simply impossible to balance, ever. Luckily, it is of little importance, since the speeds are relatively low, and the masses and displacements are rather small.

Finally, the torque applied to the crankshaft (and thus, also to the engine block) is nonsteady, with a cylinder firing once for every 1/2 revolution, and at low RPMs this will be the dominant vibration component anyway.
Also, any imbalance in power output between cylinders will manifest as additional vibration.The only viable way to address that, is to calibrate the injector opening pressure to be within tight tolerances of each other.

Well, you could also carefully equalize the compression ratio, piston-cylinder clearance and ring gaps between all cylinders, but that's well beyond the point of diminishing returns.
I'm not saying that it's bad to do so - in fact, it's an essential step for getting the most mileage and best performance possible out of an engine - but the cost involved is enormous, and in this case, the benefits would be insignificant.
The pistons, rings and cylinders will easily last > 200 000 km without any noticeable degradation in the smoothness of running (due to differences in amount of blowby present on different cylinders).
Think about it - that's 5x more than the circumference of the freaking planet, and enough to last me several years of riding - pretty much the rest of my life. So what's the point of bothering with any further "gold plating"?

No, its not an analytic scale but I do not know the proper english name for that specific type of scale.
It's the cheaper less accurate variant of an analytic scale. Guess that's the best way to describe it.

General rules of air pressure differences and platform stability still apply tough. The actual analytic scale on the picture was meant as an example.
But yeah, good is good enough.

[mark_in_manchester]

I was just reading upthread folks comments on air receivers. In the UK, anyone (even Lidl / Aldi) selling this cheap stuff has to bear liability if something blows up - so whoever they buy them off, they must be confident that they're not going to kill anyone.

My lash-up involves an ancient small compressor which can only get up to about 4 bar. I use a rusty old pub gas (CO2) bottle which would once have gone to 2000psi - and which I can still get refilled around here with Argoshield to 1000psi. i don't think 60psi is going to trouble it, though to be fair it is a little small. Perhaps I should pair it up - I have a few.

cheers

M

[Tetronator]

I was just reading upthread folks comments on air receivers. In the UK, anyone (even Lidl / Aldi) selling this cheap stuff has to bear liability if something blows up - so whoever they buy them off, they must be confident that they're not going to kill anyone.

My lash-up involves an ancient small compressor which can only get up to about 4 bar. I use a rusty old pub gas (CO2) bottle which would once have gone to 2000psi - and which I can still get refilled around here with Argoshield to 1000psi. i don't think 60psi is going to trouble it, though to be fair it is a little small. Perhaps I should pair it up - I have a few.

cheers

M

...Or they just did a cost/risk analysis. Eitherway if it does go I'll always be on the losing end if I die, rather be safe than sorry I guess.
Besides it cant hurt to put the thing in a nice soundproof box, right?

[dieseltech]

I was just reading upthread folks comments on air receivers. In the UK, anyone (even Lidl / Aldi) selling this cheap stuff has to bear liability if something blows up - so whoever they buy them off, they must be confident that they're not going to kill anyone.

Well, there is a small problem. Assuming the receivers are actually tested to their rated test pressure, that itself guarantees that it won't fail in operation - for a fair while, at least.

The trouble begins when the tank is old, and rusted inside. Although most of the time, the failure will be fairly benign - a leak due to corrosion pinholes on the bottom area, or at one of the welds (again at the bottom). The actual receiver explosions are relatively rare - but positively devastating when they do, in fact, happen.

...Or they just did a cost/risk analysis.

Quite likely.
Think about it: how often do you hear about exploded compressor receivers on the news? Quite rarely. Much more rarely than NG/LPG explosions in homes, that's for sure.

Also, one thing bothers me about the cheap compressors... on every certified pressure vessel that I've seen, the certification was always time-limited to a couple of years, and after the certification expires, they have to be either reinspected and recertified (with repairs performed if necessary), converted to a non-pressure-vessel duty (ie. cut open and used as a hopper, storage container, or somesuch), or scrapped.

The practical implication is, operating any pressure vessel with an expired certification means that all bets are off. If it fails catastrophically, the liability falls on the person(s) responsible for allowing the pressurization of a pressure vessel that was lacking valid certification.

But what if it was never certified in the first place? Who's to blame then? I haven't a clue.


In any case, even if a compressor exploded, and caused property damage / bodily harm / death, I'd imagine the burden of proof would still lie with the prosecution - especially if it happened after the warranty period expires, which is very much likely to be the case.
The retailer could always claim improper usage and/or maintenance by the operator, which would be very difficult to disprove in most cases.

I use a rusty old pub gas (CO2) bottle (...)

Oh yeah, those are quite bulletproof. Perhaps even literally - I don't think a typical handgun bullet could come even close to puncturing one.
The wall thickness on those is positively ridiculous, a good few milimeters of solid steel.


******************************

[BIG RANT]
The situation at my workplace is definitely not improving. In fact, it can be safely said that it just totally went tits up.

First, a quick bit of backstory: in order to do my current job, I need a vacuum chamber (for encapsulating linear motors).
We have only one at the moment - and it was designed by the boss, very hastily, for prototyping use only, and for a different encapsulation technology than what we actually ended up using.
In other words - although, technically, I can use it for our purposes - it requires A LOT of fiddling, hacking, and a whole roll of duct tape every time it is used (I kid you not!). Not to mention being very, VERY messy.

It totally sucks monkey balls, too, because it is top-loaded - which involves lifting the ~10+kg motor+mold assembly and carefully placing it inside, and then removing it in a similar fashion afterwards.
Also, the top is a transparent plexiglass pane which is just loosely placed on top. It gets scratched a lot from constantly manipulating it, and there are also major problems with the sealing arrangement used, as well.

Some 2-3 weeks ago, I was instructed by the boss to design a new vacuum chamber, and to "just make it taller".
However, after having used that old piece of garbage several times already, I was well aware that this was a thoroughly futile course of action. It would solve only ONE of the many problems that plagued the existing design.

So I did the obvious thing to do at that point - I designed a new, improved vacuum chamber from scratch.
It would be made using pretty much the same technology as the old one (laser cut from sheet steel -> bend -> weld the gaps airtight), so no problems there.

In the end, the extra cost (compared to doing it the way boss wanted me to do it in the first place) would be insignificant - to the tune of $100, tops - while the safety, performance, and ease of use would be significantly improved (and no more top-loading! ).
Remember, this is a one-off special tool - NOT a part that goes into the finished machines!

Now, let me put that into perspective: the vacuum chamber is used to make high-performance linear motors, which are worth at least a few hundred $ just in materials and labor cost (for a set of 3). We'll be making around 3-4 sets per month on average.
The motors are then installed into high-performance CNC laser cutters, which sell for anywhere from 1/4 to over 2/3 MILLION $ a pop (on average, just under 1/2 million).
At this time, we can build about 2.5 units per month.
That's a cash flow (not profit, though) of over 1 MILLION $ per month.

Now, just because the above simply can't be overemphasized enough:
That is more money, in one month, than the average person earns in their entire life.

So, you'd think there would be no problem with spending an extra ~$100 on a one-off basis, in order to significantly improve the safety, productivity, and the working conditions of the operator (me!).
Especially since the boss himself already authorized the purchase of over $2k worth of required tooling, and a vacuum pump worth a few thousand $ as well - all for the sole purpose of making the linear motors, so what's another $100 at this point?

Well, think again, because that is exactly the polar opposite of the truth. However insane and/or stupid that might sound.

Everything was going quite well - until the boss saw my design for the new vacuum chamber, and proclaimed that it would be "too expensive", "far too leaky" (blatantly false - it would be FAR more airtight than the previous design), and what effectively amounted to "frivolous".

So I took the matter up with the director, who has decision-making authority almost equal to that of the boss himself (it's a long story).
He's also actively involved with designing our products (and not just in the form of overseeing the design team - he actually designs many of the parts himself as well), and - unlike the boss - is a rather reasonable person, who generally doesn't turn a deaf ear to a convincing argument.

And the answer I got? "I'll have to think about it some more", immediately followed by "I don't have the time for this at the moment; for now, use what [vacuum chamber] you already have".
That was last week. Every day I keep pestering him about it, and every day I get the same response: "I didn't have the time to think about it".
And mind you, this IS an urgent matter - every day of holdup is effectively delaying the start of production, and the boss won't be pleased about that in the slightest.

So... dafuq? That's totally unlike the director that I know (and yes, it IS the same person). I'm thoroughly disappointed (and, needless to say, appalled) by this turn of events.

If it were an outright "no", at least I could understand that. But this... it doesn't fill me with any confidence, at all. Certainly does fill me with a lot of grief, though.
[/BIG RANT]

[coachgeo]

Hope getting all that off your chest helped. Actually did read the whole thing. Hang in there. My guess is the director see's your points are valid but is avoiding telling the boss cause it will bruise his ego and he does not want to deal with that issue.

[dieseltech]

Well, that issue is pretty much resolved now. A few days after my previous post, that very point was raised at a meeting of the higher-ups (including the boss and the director, of course).
I wasn't present at the meeting - which is fine by me, since they usually happen "after hours" anyway - but one of my coworkers, who was present, told me what transpired.

Basically, the general consensus was along the lines of "Dafuq is this? Why the hell are we wasting our time, and holding up production, bickering over such minor issues? Just build the damn vacuum chamber as-designed and be done with it."

Well, there's still a holdup - I've finally got the permission to make the vacuum chamber sheet metal part (already welded up, in fact), but not to order the thick plexiglass window - yet. Not until it's tested with a piece of scrap sheet metal in place of the window, first. So that's already caused over an extra week of delay.

**********************************

Also, in other news, I'll be getting a CNC mini-mill at work, sometime in the next few months, as part of "my" workshop . This is very good news for me, for a few reasons:

1. Most obviously, it means I can use it for my own purposes "after hours". Well, that actually applies to most of our CNC machinery, but at this time I haven't got a clue how to use the CNC software.

2. Related to (1), that means I'll get to know the software. Which is mostly the same, regardless of machine type (laser, waterjet, mill). That will allow me to operate the laser cutters if the need arises. VERY useful.

3. Also related to (1) - it'll allow me to rethink some aspects of my bike's design.
My design approach up until now was to avoid CNC milling if (and when) at all possible - which pretty much limited parts to laser/plasma/waterjet cutting, then TIG welding (if applicable), followed by conventional (non-CNC) turning and/or milling.

Now, although the mini-mill has a pretty small working volume - roughly 50x25(30?)x15(???)cm - it still creates a lot of opportunities.
Case in point: the backplate for the rear (drum) brake.
My original design involved an 8mm thick stainless plate, which would require turning 2 face grooves near the OD - a very tricky proposition, considering it's a relatively thin plate. Also, chucking it in the lathe would be quite difficult, too.
And in the end, it would also be pretty heavy, at ~2.2kg, since there is no easy way of making it lighter without resorting to CNC milling.

However, by utilizing the mini-mill, it obviates the need for any turning operations, saves me a few hours of my valuable time, and allows optimizing the design in ways that would not have been possible otherwise.
In this particular case, it should be possible to reduce the weight to about half of the previous value, mostly by milling out a whole bunch of triangular pockets.

**********************************

Now, back to the matter at hand: today, I've managed to finish the first pass of balancing the conrods. (FYI: no useful work got done last weekend - I was suffering from a nasty "mystery illness" that defied any and all diagnosis)

First, the big ends were balanced to within about 0.8g of each other, and then the small ends, to within about 0.5g. In both cases, that's almost exactly an order of magnitude of improvement from their initial condition.

Unfortunately, this is inherently an iterative process. Lightening the small ends will affect the big ends somewhat - but lightening the big ends affects the small ends quite substantially. So there is no point trying to get a very close balance on the first pass - it's just a waste of time.
If all goes well, the second balancing pass will be the last. If not, then the third pass will settle things once and for all.


**********************************

EDIT (@ 01 May):

Well, this week has been highly unlucky for me.

To begin with, the exhaust pipe on my car broke. It's still attached (barely!), but the spring-joint right before the 1st muffler failed somehow. No idea what exactly is wrong, as I had neither the time nor the opportunity to inspect it. Now the car runs about as loud as physically possible.
Then I cut open 2 of my fingers at work, within the span of about one hour. One with a tiny triangular scraper blade, and the other with a sharp sheet metal edge - ironically, while I was deburring/beveling ALL the edges on the part.
Continuing with the trend, the head gasket on my mother's car (2nd hand '04(?) gasser Golf mkIV) blew out. Not only is almost all of the engine oil missing, it was also largely "replaced" with coolant. FYI: she bought the car some 3 months ago, on a whim, without getting a mechanic's, nor anyone else's, opinion. Now it's pretty much a total loss, since the cost of properly repairing the engine is roughly equal to the cost of replacing the car with another used one. (* see note below)
Finally, not even an hour ago, one of my teeth decided it's had enough of this nonsense, and split itself almost completely in half while I was eating dinner.

(*): At this point, pretty much the only viable course of action is to resort to "lemon pushing":
Replace ONLY the head gasket and NO other parts - not even the head bolts! - using plenty of silicone sealant on the gasket as necessary, replenish the missing coolant with tap water, clean out the oil sludge/"mayonnaise" from under the camcase cover and the dipstick tube, and refill the oil with the cheapest $1/L (no, seriously!) crap that the oil change garages "claim" to be "engine oil". Basically, a "this S.O.B. has to run right NOW" kind of fix. Do NOT drive the car under any circumstances, other than a few minutes to check for major leaks.
Then wash the engine bay - incl. engine - in the cheapest way possible, and find some gullible moron who will buy that pile of junk.

Sad? Undoubtedly. Unfair to the buyer? Absolutely. A d!ck move? Of Washington Monument proportions, there can be no doubt about that.
Unfortunately, in Poland, this kind of thing happens countless times, every single day. In fact, it's very likely that this exact thing happened to this car shortly before it was bought by my mother.
Very few people can afford to sell off a car that's relatively new and still runs fine - in fact, that's a great reason NOT to sell.
The vast majority of the time, the reason for a car being sold is because there is a serious problem with it (or a whole lot of smaller problems), not economically viable to repair - or it's about to kick the bucket outright.

A large part of the reason is the huge income disparity, both between the rich and the poor (there's a huge amount of people who earn very little, and a very small number of people who earn obscenely huge sums of money), and between us and the "civilized" nations.
It's not in any way an exaggeration to say that the average Pole earns about as much in PLN, as the average German earns in Euro (the PLN:Euro exch. rate is very roughly 4.2:1). Yet car prices are roughly the same everywhere, after factoring in the currency exchange rates in different countries.

Very recently, there was a major political incident between Poland and Germany, when the German gov't wanted to institute a law stating that truck drivers employed in foreign countries, while driving on German soil, be paid the same hourly rates as German drivers. With the extra money coming from their employers, of course.
While it sounds like a great deal for the drivers, it would actually put a lot of the trucking companies out of business altogether, since trucking any cargo through Germany would not only be no longer profitable - it would be a net loss for the company in most cases. So there was a huge political backlash because of that, since it would badly hurt our economy as a whole.

From this, you can probably draw your own conclusions.


**********************************

In other news, I've had time to carefully analyze my situation regarding the new (not yet bought) compressor. After carefully considering all the relevant factors, I arrived at the conclusion that it'll be preferable to buy a 270L, 5.5kW 3-phase compressor (belt drive, two-stage pump), and for the time being, fit a 3kW single phase motor to it.

A 3kW, 1400rpm motor would require a pulley only slightly larger in diameter than the stock one - the stock motor is 2800rpm, and about the same frame size as a 3kW 1400rpm one. That will run the pump at slightly more than half the stock RPMs, with correspondingly reduced output airflow, of course. Still considerably more powerful than the old POS compressor, though.
This way, I can use the stock belts, avoid having to significantly modify the compressor - other than my extra aftercooler and filters, but that's getting installed in any case - and in the future, it's a simple matter to revert back to the stock 5.5kW motor once I have 3-phase power available.
Which should pretty much obviate the need for a 2nd compressor, saving space and $$$ - between the 5.5kW motor, 2-stage pump, and 270L tank, it should be enough for pretty much any task I can possibly require to accomplish, including running a pressure pot sandblaster.
Also, it will still just barely fit in my car if need be, although not vertical, but lying on its side. However, at around 150kg, it's definitely a three-man job.

The compressor itself costs roughly $1200-1400 depending on the source, and a new 3kW 1ph "capacitor start capacitor run" motor is around $200-250 - pretty much peanuts at this stage, and in the (distant) future, I can repurpose the motor for something else, after converting the compressor back to 3-phase power.
Conversely, in the meantime, I could also use that 3-phase motor for some other purpose, although I don't have any meaningful application in mind at the present time.


**********************************

EDIT (@ 15 May):

OK, the new compressor has arrived. In case anyone is interested, it's a Fini BK119-270-7,5.
It cost almost exactly the equivalent of $1200 (incl. free shipping).

Regarding the duty cycle values I posted earlier - sure enough, the motor nameplate says "5.5kW S3 75%".
"S3 75%" means it's rated for intermittent duty, at a maximum of 75% duty cycle.
Meh, doesn't matter for the time being anyway, what with the single-phase motor swap.
And if it does prove inadequate in the future, I can always slap on a proper 5.5kW S1 (continuous duty) rated motor. 3-phase motors are "relatively" cheap.

I have to say I'm quite pleased with the quality. It's quite solidly built, certainly a vast improvement over some chinese crap.
In fact, the only parts that I could positively identify as having been made in China are the power cables. And even then, they appear to be of fairly decent quality. Maybe not top-of-the-line, but certainly good enough to do the job, and also not to shatter in freezing cold conditions.
The compressor even has a real, adjustable motor overheat protection device, installed as an integral part of the pressure switch.
Also, I like the air filter design: it has a paper filter cartridge - fairly reasonably sized for the intended airflow - covered by a dry foam pre-filter, which can be removed, washed and reused.

Of course, the compressor is not perfect. There are a few minor issues I have with it, but nothing that would have any negative impact on safety.
I was not impressed with how it was secured to the wooden pallet: the hold-down bolts weren't tightened sufficiently, and the washers were mounted the wrong way (with the sharp side facing the paint!), causing the paint in these areas to be deeply gouged (in some places right down to the bare metal) when the compressor kept shifting slightly on its pallet during transport.
Thankfully, it's not a safety issue, since only the sheet metal "legs" are affected.
For now, as a temporary fix, I applied some grease to stop the exposed steel from rusting; later on, I might get around to implementing a more permanent repair.

Overall, I'd say it's still excellent quality for the money, though.


In other news: just this morning, my coworkers next door have started building "my" CNC mini-mill. So in a month or two, it should be finished.

Also, I'm finally done with the connecting rod balancing. They're all within about 0.15-0.2g of each other, maybe less than that (both for the big and small ends) - easily good enough for the job, and pretty much right down to the practical limits of my equipment in any case.

[dieseltech]

Well, it's been a while since the last update. The original plan was to hold off on updating until the compressor is finished.

But, as usual, things got derailed along the way, and the estimated completion date is getting repeatedly pushed further forward.
So I decided to post an update anyway, especially since now it's also directly pertinent to my build.

But first...

EDIT (@ 15 May):
(...)

In other news: just this morning, my coworkers next door have started building "my" CNC mini-mill. So in a month or two, it should be finished.

Well... now THAT is getting repeatedly delayed as well. Massively so, in fact.

To put it in perspective... a grand total of 3 parts have been assembled so far. That is NOT a typo - three parts (the main chassis - which is supplied by a subcontractor - and 2 stiffening braces).
And now it's been tossed into the corner and largely forgotten about. ZERO progress in the last month.
That is beyond frustrating - especially considering that I urgently need it, in order to be able to do my job properly...

EDIT (@ 29th July):
Just today, my coworker (responsible for building the above-mentioned mini-mill) informed me that there isn't even a snowball's chance in Hell of getting any work done on the damn thing in the month to come, at the very least. And new units continue to be ordered at an absolutely impossible rate. Fun.
Problem is, we're severely understaffed, by at least a few tens of people (current staff - ~150-200). The number of new orders for our laser cutters - and other CNC machines, too - being placed every month seems to be growing without bound; far faster than we're able to hire new workers to build them, in any case.

----------------------------------------

With that out of the way, here's a summary of the recent progress (and some of my idle musings as well):

1. The compressor.
I finally got the required 3kW 1400rpm single-phase motor, after over a month of waiting for it to be manufactured (I wish it were a joke...).
Also got a nice cast iron pulley for it - theoretically it would've been possible to reuse the stock pulley, but I wanted to minimize the amount of effort involved in converting it back to the stock 3-phase motor in the future.
In any case, work on the compressor is getting repeatedly interrupted: first I got sick, then the weather made any progress unfeasible, tomorrow there are other circumstances precluding getting any work done... GAH.
At this rate, I just might be able to get the damn thing up and running before the winter hits, again making further work on the compressor practically impossible until next spring.
And if you're wondering - right now the compressor is in pieces. The motor is not installed (in fact, the "new" pulley hasn't been painted yet!), the pump is sitting on the floor (can't align the pump pulley without the motor having been installed first!), and the aftercooler isn't even close to being ready to install.

2. The welder.
This is something you didn't know about (yet, anyway). To make a very long story short, I've been working on upgrading the control system of my 3-in-1 welder/plasmacutter, as well as a couple other misc. tweaks.
It entails a LOT of work, and because of the compressor, all work on the welder has been suspended until the compressor is finished.
If all goes well, I might have the welder back online in about a year from now. Until then, NO welding/plasmacutting is possible. Fun.

3. The new lathe (not yet bought!).
I've checked the dimensions of the basement layout - it turns out (pun not intended!) that it should be possible to lower the entire lathe into the pit with my chain winch, and subsequently roll it along the floor on some furniture transport rollers, through the entire basement, into its "final" position. There is one small step along the way, but a few right-sized blocks of wood should solve that problem.
At this point, I'm undecided as to which lathe to buy: the one I've posted about earlier, or a pimped-out unit which is roughly 40% more expensive, but has a LOT more features, and is roughly twice as heavy (over half a ton!) for the same physical size.
Next spring, when I'll (hopefully) have enough $$$, I'll give the sales rep a call, and ask for a complete technical spec on both units - their online shop only has an extremely abbreviated specification available for viewing. Then I'll decide which one to buy.

4. The beveling machine.
I've decided to buy a beveling machine: (click here to see the unit I'm buying)
I have an almost identical unit at work, and it's an incredibly useful tool to have. In fact, the reason I'm buying it right now, instead of in the future, is because I've already got a whole pile of parts that are waiting to be beveled.
Now, in theory, I could bevel those parts at work - but in practice, it would be way too much hassle (since I would have to notify the director, and take certain steps so that 'm not wrongfully accused of stealing company property when taking the finished parts back home), and in any case, it's also extremely useful for preparing edges for TIG welding - which pretty much requires having a unit on site, anyway.

5. The shaft balancer.
After much deliberation, I've decided against attempting to build my own dynamic balancer (which was something I've been considering for a while already).
The only part in the bike which cannot be adequately balanced with a simple static balancer is the crankshaft. And, technically, also the camshaft, although it is in fact impossible to balance, due to not having any counterweights - not to mention also not having any extra metal that can be removed for balancing purposes.
For everything else, a trivial 4-bearing static balancer is quite sufficient, practically speaking: the engine will have uncorrectable higher-order vibration due to being an inline-4, and there will be unavoidable torque ripple as well.
So, the preferred approach would be to outsource the crankshaft balancing to a reputable workshop (TODO: find such a workshop, preferably within the city limits).

EDIT: Scratch that. Not going to happen, period.
I only found a few workshops that offer such services - one is a known no-go due to notoriously low quality of their services and unrepentant corner-cutting, and the others are all "racing"/"tuning" shops who only do "full" balancing (pistons+conrods and then balancing the crankshaft with calibrated bobweights).
Such "full" balancing is not only redundant (I already did the pistons and conrods myself), but also unnecessary for an I4 diesel with such low max RPMs (by racing/"performance" standards, anyway)* - not to mention, ridiculously expensive.
(*): In this instance, balancing the crankshaft bare (no bobweights) would be perfectly adequate; using bobweights would only waste time and money, for no real gain.

As of right now, the first order of business is to check the static balance, and then I'll spin it up on my static balancer with an electric drill, and feel for any excessive vibration by hand (while it's spinning down, not being driven).


And, last but not least, the bike build itself:

Recently I've been pondering the issue of the clutch assembly. Originally, my idea was to reuse the stock (OEM Ford parts!) clutch disc and pressure plate, replacing only the throwout bearing.
However, a close inspection of the clutch disc revealed that it's near the end of it's useful life - one side is noticeably more worn than the other, and the more worn side has only ~0.6-0.75mm of lining material left over the rivet heads.
Also, both the disc and the pressure plate are thoroughly corroded, in part due to having been chucked into the corner of the shed, and forgotten about, for a good few years - that was long before I had any plans to build a diesel bike out of that engine, though.
Finally, the pressure plate wear surface is, well, rather worn. In theory I could remachine it, but that's a lot of hassle, and even then the disc would need replacing - and it's very poor form to mix-and-match discs and pressure plates from different manufacturers, let alone mixing used and new parts.

Now, in theory, I could just remachine the old pressure plate, stick the old disc in there, and it would work just fine, for a while at least - but unless it can last the entire useful life of the bike (or my own, whichever runs out first), there would be hell to pay, since replacing any clutch components involves literally taking the entire bike apart - which is a possibility I would prefer not to consider, ever.

And given their condition, I would say they will NOT, in fact, last long enough for that, even if they do not suddenly fail due to corrosion first.

So, a clutch kit is in order. I've managed to spy out a nice Sachs kit in a local shop for the equivalent of ~$85. That's quite damn cheap for a 3 part kit (incl. a packet of special spline grease). And that price is with no discount applied.
Curiously, an equivalent LuK kit is much more expensive, at >~$110, even though they're about the same, quality-wise.
Next week I'll ask my usual supplier about this - I have a substantial discount there, so maybe I can get an even better deal.

EDIT: Nope, no dice. No surprise there, though - those are some thoroughly obsolete parts, quite hard to obtain even in the best case scenario.
I'll just buy that $85 Sachs kit where I found it. As a nice bonus, they also have a few other useful parts in stock:
- the thermostat (the OEM one seems to be working fine, but it's 30 years old by now... better replace it, at $11 it's cheap anyway),
- the gearbox input shaft seal (the proper, directional version with helical ridges; I have a full gasket/seal kit for the engine, but it contains no gearbox seals),
- the crankshaft thrust bearings (the OEM ones show some minor wear, gotta mike them to find out exactly how much, though).
/EDIT

In preparation for the new clutch kit, I finally got around to checking the flywheel surface. Sure enough, it was somewhat worn, too. So on the lathe it goes. But, being so large for the tiny P.O.S. lathe, will it fit?
Well, I'll be damned - it cleared the lathe ways... by a little over 1mm.
In the end, I had to remove just a hair over 0.15mm from the front surface to make it nice and flat again - that's just over half of the permitted remachining limit (remove too much, and the springs on the clutch disc will start to rub against the flywheel bolt heads... bad!).
After remachining the face, there were a few hard spots remaining in the wear track left by the clutch disc linings, and my weaksauce lathe can't handle such hard spots properly, so I jury rigged up a lapping jig using an old bench grinder wheel (specially prepared so that one side is very flat), pressed against the flywheel face by a rubber bung, and spun the flywheel at the max speed the lathe can manage (~300RPM), for some 2-3 hours, to get rid of the raised hard spots. Worked out quite nicely, and smoothed out the turned surface as an extra bonus.

Before the flywheel could be turned, though, the dowel pins had to be removed. One pulled out fairly easily, suffering only minor damage; the other 2 required serious persuasion, though, and got completely trashed in the process.
So now I also need to make 3 new dowel pins (and yes, they are non-standard!), and also a small steel mandrel to drive them back in, square to the flywheel surface, without damaging anything in the process.
Next time I'm out shopping, I'll grab a suitable 12.9 grade bolt, to make the new pins out of. This is, by far, the easiest, cheapest, and fastest way to get very small amounts of heat-treated steel rod of a known grade.

Finally, I inspected the flywheel ring gear, and found that several teeth (roughly corresponding to the "preferred" stopping positions for the engine when it is shut down) are significantly worn where the starter pinion engages the ring gear - but only on the gear face; the tooth flanks are pretty much unharmed.
It would probably work just fine the way it was... but why take chances?
I carefully tapped the ring gear off the flywheel, cleaned up the mating surfaces, and reinstalled it facing the other way, following the procedure detailed in the service manual: heating the ring gear to ~250 deg.C in the kitchen oven, and installing it on the flywheel while still hot, using asbestos gloves to handle the searing hot ring (unfortunately, no asbestos gloves for me, so I had to make do with a pair of pliers instead).

The ring gear is normally a very tight fit on the flywheel, and attempting to reinstall it without properly heating it first will invariably result in damaging either the ring gear or the flywheel (or both!).
Heating it to the recommended temperature, on the other hand, makes it "enormously" oversized, so that it just lazily drops into position by gravity alone.

So now I have a remachined flywheel, with the pristine sides of the ring gear teeth now facing the starter motor. Now I just need to make and install the 3 dowel pins, and balance the flywheel (and then the new pressure plate as well), and it's set to go.

Also on the agenda: making a clutch disc centering tool. It's very simple, really, just a stepped steel rod turned to the right diameters. It's also useful for verifying that the new clutch disc is free from runout, before installing it.


I'll take a few photos of the flywheel next time and post them... I was about to say, "tomorrow", but I forgot to bring the camera tripod with me, so it'll have to wait at least until the next weekend.

EDIT (@ 2nd August):
OK, here are the photos (click to enlarge):



The worst of the ring gear teeth. Note that the ring gear has already been flipped - that's why the worn sides are not on the starter motor side anymore.
(this was cropped from the original, much bigger image.)

Also, this is about as close as I can get with my camera. This was taken from about 25cm with max zoom. Without zoom, it can be focused down to about 4-5cm.
Note the poor depth of field - the teeth in the left upper corner are already out of focus. The basement is poorly lit, and even with an extra lamp thrown in, and max shutter time possible, I had to back off the aperture to get a decent exposure.
Still, not at all bad for a camera that I got for under $30.




With the flywheel rotated by half a turn. Uncropped.

The letters stamped on the ring gear were originally on the starter motor side. Interestingly, contrary to expectations, there was very little raised metal around the letters, much less than would normally happen when plastically deforming steel. It took only a couple of seconds to stone the irregularities flat.




The whole flywheel. The hard spots are easily visible, since the motorized stoning operation left them very smooth and shiny.




And a closeup of the worst hard spots.
The pitted appearance is caused by machining - since the "hardened" skin is very thin, a phenomenon similar to "case crushing" occurs, with tiny chunks of the hard skin separating from the softer base metal.
In this case, it looks considerably worse than it really is, due to the poor lighting, and the angle of illumination.
In practice, the pitted area is so tiny, compared to the entire friction area, that it will have virtually no effect, as far as the clutch operation is concerned.

Sure, the surface isn't perfect, but it's FAR preferable to just installing the new clutch and pressure plate on the old, worn out surface.
And in case you were wondering - no, it wouldn't have been possible to get fully rid of the hard spots by cutting the surface deeper. Not without exceeding the permitted remachining limit, in any case.




The trashed clutch locating dowels.
The middle one I was able to extract with reasonable force, although it was still somewhat damaged in the process.
However, the other 2 I had to undercut with an angle grinder, to be able to get a sufficiently good grip on them.

No, I do not have the proper tool for this job. In fact, I have no idea what the proper tool even looks like.
I just used locking pliers, and a wrench to lever it up. No need to worry about damaging the flywheel surface in the process, since it was going to be remachined anyway.

I haven't made the new dowels yet. Still need to buy a suitable bolt, as mentioned earlier.


And finally...



This took me about 7-8 hours yesterday.

That's a bottle jack from an "el cheapo" hydraulic press. Ever since I bought the press, one of the check valves was leaking slightly. Under load, the load would slowly release, while the lever would rise by itself (and there are no springs involved!). Especially at high loads, you had to pump the lever nearly constantly to maintain/increase the load.
At the same time, I found it annoying that there was no reliable indication of the force being appplied, other than how hard it is to push the lever down.
Also, the jack was not sitting straight. It was tilted at a slight angle, causing all sorts of problems.

So I fixed all of these issues:

The leaking valve was trivial to fix, just whack the ball with a hammer (through a relatively soft pushrod) to make it seat properly.
Now it's working much better - no visible rising of the handle.
There's still a tiny leak somewhere, at a rate of maybe 1 bar per second, or even less, but it's not really relevant for most possible uses of the press.
That would only be an issue if I had to clamp something for a long period of time, with a consistent force. Can't really imagine a need for such a procedure, though.

The piston is 42mm in diameter. That works out to around 870 bar for the rated 12 ton load.
So I bought a 1000bar glycerin-filled gauge, and the fittings for it, for a total of ~$40.
Machined a suitable flat on the jack's side (not visible in the photo, unfortunately), and drilled and tapped a 1/4" hole, plus 2 small diameter holes to connect it to the main cylinder.

Finally, while doing the above, I discovered that the bottom of the jack's base was significantly warped, and not at all perpendicular to the main cylinder. Easily enough fixed with the lathe.
I had to remove a total of roughly 1mm of material. Now it's not only accurately perpendicular, but also properly flat. And the jack no longer wants to shift sideways in the press under load.

In case you are wondering - no, I couldn't have simply bought a proper press with a top-mounted cylinder, separate pump, and built-in gauge.
Yes, these are very nice. Unfortunately, they are also much more expensive. A 20-ton press of this kind is roughly 4x more expensive than the one I have. Even a 12-ton is still roughly twice the cost.
I bought this press a few years ago, when the budget was very tight. Spending the extra $200-250 on a better press would have meant greatly delaying other, equally (or more) important purchases.

Of course, if I were to buy a press today, I would get the above-mentioned version without hestitation - much better quality and less hassle. But sometimes, compromises are required.


--------------------------------------------------------------

EDIT (@4th August):

I've just picked up the new clutch kit, thermostat and gearbox input shaft seal.

The latter 2 are rather unremarkable, other than being of good quality.
The clutch kit, however, is... very interesting, to say the least. More on that in a moment, though.

I've also measured the crankshaft thrust bearings to check for wear. Well, there isn't any that I can measure, at least.
I don't have a micrometer (yet), so I used my electronic calipers - both sides are within 0.01mm of each other, despite the side facing the clutch being visibly more worn.

Unfortunately, I wasn't able to measure the endfloat - at this point it would take around an hour just to set everything up for the measurement, and then put it back in storage.
However, I've just assumed that since the bearings have no measurable wear, there is little to be gained by replacing them, so I didn't.


OK, back to the clutch kit (photos of new+old coming soon!):
As advertised, it contained 4 components:
- clutch disc
- pressure plate
- release bearing
- tiny packet of dedicated clutch spline grease

The release bearing is fairly unremarkable, really. It does appear to be fairly well made.

Now, the clutch disc is very interesting: although the dimensions, splines, and # of spring "windows" match the OEM disc, that's about all in terms of similarities:

The OEM disc was a very simple affair - the splined bushing and driven plate were combined into a single, rigid piece of metal. There were 4 springs - 2 of very high spring rate (thick wire), one medium rate, and one with a very low rate; quite asymmetrical.
Additionally, there was very little in the way of any provision for engine/gearbox misalignment.

One thing that's immediately apparent about the new disc, is the weight. It's considerably heavier than the OEM unit.
Also, the spring are very different: 2 springs made of 3.1mm wire, and 2 springs made of 3.3mm wire, with both of the latter having a smaller spring (of opposite helix handedness) inside them as well. Were there resonance/"spring float" problems?

What's also immediately apparent is that the new disc can handle considerably more misalignment than the OEM one. What's not readily obvious, though, is that it also has an internal rubber(?) damper as well - the splined bushing has a small but noticeable amount of angular backlash, and trying to turn it (relative to the driven plate) results in an obvious rubbery feel to the rotation. This was presumably done to minimize gear rattle at idle; a problem that older diesels were fairly notorious for.

Finally, I measured the thickness of the friction linings on the new disc: 1.65-1.70mm over the rivets, ergo the OEM disc had only one third of its life remaining in any case.

The pressure plate gives me mixed feelings:
On one hand, it is reasonably solidly built. Friction ring is cast iron, as it should be. The surface finish is fairly good, with only very faint chatter marks visible; can't be felt with a fingernail, though.
Also, the sheet metal cover is not painted, but instead coated with what appears to be galvannealed zinc, for superior corrosion protection.
On the other hand, though, there's a substantially sized ding mark on the sheet metal cover, right out of the factory sealed box - was the damage done before or after it was assembled? Must've been quite an impact.

Also, about half of the sheet metal edges are absolutely razor sharp. Seriously, I got a nasty little cut just by carefully taking it out of the box.
Really, Sachs? Is it so hard/expensive to run the covers briefly through a vibratory tumbler to dull the edges slightly?
For comparison, the sheet metal edges on the OEM pressure plate are all sufficiently dulled as to be safe to the touch.

And one final rant: the clutch disc was separated from the (greased) pressure plate friction ring only by a single layer of corrosion protective paper, which has already started to become soaked with the excess oil/grease.
Now, depending on how (and for how long) the box is stored, the clutch disc could be contacting the increasingly grease-saturated paper for years - and the last time I checked, a greased "dry" clutch disc isn't at all good for transmitting the rated engine power.

All in all, this kit is still great value, though. And IMO, a nice upgrade over the OEM hardware, even if you only consider the substantially upgraded clutch disc.
As a nice bonus, it was quite cheap, too, as far as clutch kits go.


(photos coming soon - again forgot to bring the tripod with me, duh!)


--------------------------------------------------------------

EDIT (@8th August):

Still no photos. My friend is out of town this weekend, so I wasn't able to use the workshop. No real loss, though, seeing how we're in the middle of a ludicrous heat wave.
But that's not the point here.

Well, the last week sure was... eventful.

I was assigned 2 more assistants at work (for a total of 3) - one on Monday, and one the Friday before that. Both totally green; one of them also very reckless and irresponsible.
And I'm too overloaded with perpetually-urgent work to be able to properly train them ATM - the best I can do is to try and minimize the resulting damage. There is some hope, though - I've given them a bunch of trivial, menial tasks to do, and we do seem to be making a bit more progress than before.

And things were going fairly well - until the boss appeared on Wendesday.

Now, to put things in context: when I was transferred to my current position in January, I received the "prototype making" tools and technology from the boss himself, and was told to effectively mass-produce the parts - and in the meantime, to also design and build new, proper tools, and improve the manufacturing technology.
Sounds fairly reasonable, right?
Well, the emphasis was strongly on "production first", which is an approach I strongly disagree with, but whatever. Another few months at this rate, and I'd posess all the special tools that I need in order to finally manufacture these things properly and efficiently.

For the past few months I've been continuously running into newly surfacing problems (concerning both the production process and the end result), and do whatever it takes to prevent them from reoccuring - or at the very least, cure the symptoms, if fixing the underlying cause wasn't possible.
Those are the kind of problems that usually won't appear when all you're making is a few prototype units - and if they do, most of them can be overlooked, because hey, "it's only a prototype".
But in (more-or-less) mass-production, it's a whole different story.

And then, last Wednesday the boss paid me a visit, inquired as to the details of the current production process / technology, and told me to drop a lot of what he considered "extra, frivolous steps". Steps that were being performed specifically because they were all various solutions devised to resolve a whole host of above-mentioned problems.
Including one improvement that I was in the middle of testing at that very time - and the initial results already appeared very promising, in terms of both improving the quality and reducing the amount of work involved. Nope, no dice.

Let me reiterate this: I was effectively told by the boss: "screw the quality, just churn'em out fast". Which totally ISN'T fine, considering that if there are any deficiencies discovered in the resulting products, I will be held to blame.
Especially if they fail in actual service, and not during our in-house testing, since that's a lot more expensive to fix.

At that point, between the poor pay, the somewhat crappy working conditions, the constant lack of a sufficient number of assistants (until just a few days ago), the ridiculously long waiting times for both tools and raw materials (waiting "only" 3 months for eg. an $80 pair of plastic electronic calipers, or other, even cheaper tools? Not to mention 8+ months for a mini-mill that takes under a month to build by my coworkers next door? Seriously?), and the lack of A/C in a notoriously overheated workshop, that was it.
The steaming pile of B.S. I was just handed by the boss was the straw that broke the camel's back. At that point, my rapidly depleting supply of fucks left to give has finally run dry.


***

As of right now, with every passing week I feel increasingly dead inside.
Over the last couple of years, I've already had to toss most of my wishes and ambitions into the garbage bin (sometimes even literally, in fact) due to various practical limitations of time and/or money.

Some people wish for everlasting life, which is a concept I find most abhorrent, since the only thing keeping me relatively sane in this hostile world is the certainty that some day, sooner or later, the suffering will end permanently.
If a person was cursed with the state of "being unable to die", while otherwise bound by all the laws of this world, such an existence would be virtually indistinguishable from what is commonly described as the state of "being in Hell", including the "everlasting punishment" part.

***

TL;DR, here's what it entails in practice:

1. This Friday, I've applied for a (broadly similar) job at a different place. According to my sources, both the pay and the conditions are considerably better.
3 new job openings appeared just a few days ago. I don't normally believe in coincidences, but...
Unfortunately, it's considerably further away from home - roughly a 40-45km round trip (I've yet to map out the best route), as opposed to ~15km as of right now.
Considering the TCO of a car (not just the consumables!), roughly 1/3 of the paycheck will be lost on the commuting costs. Public transportation is out of the question, due to the tricky location.
At least it's a nice, relaxing drive through the scenic landscape of the middle of nowhere - as opposed to raging your way straight across the city during rush hour, your progress constantly foiled by the EVIL traffic lights.

2. All things considered, this finally makes the ownership of a bike a practical proposition.
If this new job works out, I'll be getting my own bike, possibly as early as in 2017. Sadly, not a diesel, though - at least, not for the ~10 years to come.
I got to ride my friend's Yamaha XVS650 a few times, and I find it generally to my liking.
Although I'll probably get a similar 800cc bike myself, rather than a 650, in accordance to the infallible doctrine of MORE POWER!. This would result in roughly similar performance to this 1.6D bike that I'm in the process of building.
In any case, the first order of business will be to rent (or buy) a garage located reasonably close to home - which is to say, within ~10 minutes of walking at most. I'll see about that when I can actually afford to buy the bike, though.

3. ???

4. Profit (?)

[dieseltech]

First things first, here are the "missing" photos that were being referred to in my previous post: (as usual, click to enlarge)

The new pressure plate:




The new clutch disc:




The old clutch disc:




Note the difference.
Just so that we're on the same page - no, this is not a clutch kit from a different engine or car or something. This is the real deal - both the old and the new clutch kit are the correct parts for this engine+gearbox.

Also, it can't be conveyed by a picture, but the old disc had enormous angular backlash. The new disc has ~1 degree; the old one had to the tune of 15-20 degrees (!) before any of the 3 heavy springs were being loaded.
In case you're wondering - that wimpy 4th spring is very weak, even by human standards, and does next to nothing useful.
It's interesting how this design managed to work "well enough" to be approved by Ford. Well, I guess the customer expectations were much lower in the 80's than they are now.
NB, I have no idea how this actually performed, since I never got to drive a 1.6D Fiesta; this engine+gearbox was bought at a scrapyard.


************************************************************

Now that we have this out of the way, it's time for something new.

As you can probably imagine, I've been messing around with the clutch recently.
I had 2 major questions to answer:
1. What is the torque limit of this clutch? (relevant to possible turbocharging)
2. How do the actuation (release) characteristics look like exactly?

And now I have my answers.

For (1), I took the old clutch disc (don't want to damage the new disc!), put a M16 10.9 bolt+nut through the center, tightened it to 210Nm (max my torque wrench can handle), degreased and assembled the whole clutch assy, and then...
The first measurement resulted in my torque wrench maxing out @ 210Nm without any slippage. That can't be right at all.
NB: it's a good thing that the cheap 1/2" universal joint didn't snap under the heavy load.

Before taking any further measurements, I loosened the pressure plate, so that the screws were just barely snug, and forced the disc through several turns with the wrench, to knock off any surface high spots that were messing up my measurements.

The next series of measurements was much more consistent, as well as within the bounds of sanity.
140-142Nm.

Note: the old clutch disc had a broken-in surface - however, the flywheel and pressure plate had fresh surfaces, not yet broken in. Also, the old disc was more than 2/3rds worn out.
It's highly likely that the actual max holding torque would be even higher with the new disc, after it fully breaks in.

Photos:










Now, as for (2), this required carefully compressing the assembled flywheel in the hydraulic press.
The pressure gauge had to be replaced, since it would be impossible to read any useful values off the 1000bar gauge. A 40 bar gauge was temporarily installed in its place.

Here's a photo of the test setup:




Not exactly the paragon of measurement accuracy, but good enough to get the job done.

To make the release bearing fit the ram properly, a spacer had to be used. Luckily, there was a suitable piece of scrap brass right on top of the pile:




Fits perfectly, both inside and outside:




Two series of measurements were made, both using the new clutch disc: one with the pressure plate installed normally, and another with the pressure plate shimmed up by 3.2mm above the flywheel surface.
This was done in order to simulate the thickness of a roughly 80-90% worn out clutch disc.

After taking the measurements, including compensating for the effects of the ram return springs, and cracking the data, here are the results:
(note: no attempts at curve-fitting were made)




Note: Measurements were taken every 0.5mm. The release point is defined as the smallest release bearing displacement which allows the disc to be moved around freely, without any resistance.
In both cases, at 7.5mm displacement, there was ~0.6-0.8mm clearance between the disc and the pressure plate, ie. more than enough to fully disengage the gearbox under normal operating conditions.

NB: these numbers are lower than what I expected. Might have to revise the "power clutch" hydraulic amplifier design slightly, to reduce the maximum force output.

************************************************************

And we're back to the subject of turbocharging.

(Much) earlier, I've stated that "I'm probably not going to be turbocharging this bike".
However, in light of the new facts, and my further deliberations, the situation now stands as follows:

1. It is in fact physically possible to locate the turbocharger on the bike, without undue interference with other major components. It would be located roughly in front of my right knee, with the exhaust side facing towards the direction of travel (ie. opposite of how it would be normally mounted in a transverse engined car).
The hydraulic pump might have to be moved somewhat, but there should be easily enough room for that.

2. Assuming a perfectly reasonable target of 130Nm, the engine would be capable of 65kW (88HP) @ 4800rpm, an increase of ~57% over naturally aspirated, assuming the use of an RPM-dependent boost compensator to negate the torque fall-off at high RPMs (this can be done non-electronically, using only pneumatic+mechanical means; possibly even with zero moving parts).
Without such a compensator, it would still develop 130Nm @ ~3000rpm, but the max output would drop to approx. 57kW (77HP) @ 4800RPM, due to the shape of the torque curve (also, adjustments would be a lot easier).
Still a substantial gain. Even more might be possible after the clutch fully breaks in.
NB: it's not feasible to gain even more power by pushing for higher max RPMs. Past the rated redline there be valve float, and also the redline specification is unusually narrow for the era(+/- 50rpm).

3. The gearbox is probably capable of handling that, no problem.

4. The final drive components are another story, though. The ALDA would need to be disabled (vented to atmosphere) in 1st and 2nd gears, otherwise things will fail catastrophically.
Incidentally, the 3rd gear works out to ~105% of rated torque for the final drive gearbox, assuming 130Nm from the engine - so we're fine from there onwards.

5. Converting the injection pump to turbo operation is no big deal - I have another, otherwise unneeded VE pump that has a destroyed housing (lost in shipping...), but an intact top, including an ALDA.
Since the OEM pump has to be fully disassembled for resealing anyway, (re)assembling a frankenpump is a straightforward operation.
The VE's also have ridiculous delivery margins built into them. Readjusting it to 160% of "rated" output should pose no problem - and even if it were to prove impossible, I have other ways around that.

6. Intercooling. At this power (boost) level, none is required. The End.
(Note: the upper limit is the peak EGT rating of the turbine. IIRC 750 deg.C or thereabouts. Red hot, more or less.)

7. Exhaust muffling. With the N/A engine, it might be quite tricky to make a muffler that will both fit in the (very limited) space available, and be effective at muffling the excess noise. Especially since you want to also minimize the flow restriction that it imposes.
The turbo largely takes care of this problem, since the compressed exhaust gasses are expanded back to atmospheric pressure, greatly decreasing the exhaust noise level. A much smaller muffler is required - in fact, depending on the desired/permitted sound level, a muffler might not be needed at all. And exhaust backpressure is much less of a concern, too.

8. Finally, cost.
Now, it's true that turbocharging the bike is going to be expensive. To the tune of $2K+ total, if you include the man-hours (really, it's mostly the man-hours).
However, it's pretty much chump change when compared to the TOTAL cost of building the bike, which I would (very) roughly estimate to be on the order of $50K++.
And the improvement in performance far outweighs the increase in cost.

[UAofE]

6. Intercooling. At this power (boost) level, none is required. The End.

Intercooling is beneficial at every pressure level.

Say you're planning 10psi to get your 77hp. With an intercooler you could lower that number to 7.5psi, further increasing power and efficiency by lowering pumping losses (exhaust drive pressure).
Or 134cc/min (2gph) water/methanol injection would have a similar effect without the complicated air plumbing. In addition, you get the benefit of it's carbon removal effect.

[dieseltech]

Intercooling is beneficial at every pressure level.

Indeed, it is as you say. It is, in fact, essential for maximizing the power gain that can be extracted from a given setup.
Charge air density is maximized, while also minimizing the EGTs.

However, it also has its drawbacks:
- increased cost,
- increased turbo lag (due to extra system volume),
- increased size and weight (the intercooler & pipes are very bulky),
- without electronic engine control, it's not possible to utilize it to its full potential.

Before go any further, let me reiterate one major point:
There exists a hard limit on the attainable engine torque, imposed by what the clutch can handle.

Therefore, in this particular case, the goal is not to maximize the output power/torque.
That would just cause the clutch to slip, and be rapidly destroyed in the process.
Rather, the goal is to approach that hard limit as closely as possible, without causing clutch slippage. So a safety margin of some 10Nm is required at all times.

In this case, that torque limit is still far below what could be safely extracted out of the engine with this K03-006 turbo installed. Even without an intercooler.

Also, just to get this out of the way: replacing the clutch for an uprated "racing" version is out of the question, simply because no such clutches/p.plates exist for this engine/gearbox type. No surprise there, seeing as it is entirely unsuitable for what would pass as any sane definition of "racing".

Finally, I (generally) have a very utilitarian approach to things, in terms of the benefit/cost ratio. If I do this, or that, how much will it improve things? And what will the total cost be in the long run?

*************

With that in mind, let's go back to the list then:

As we've already established, cost is not a major issue here.

Turbo lag... that can be annoying, but certainly not the end of the world.

Now, the extra bulk definitely is a dealbreaker here. Installing just the turbo is going to be a highly nontrivial exercise already.

There is simply no room for an intercooler here.
A FMIC won't fit, even a custom-made one, because it would require the entire front end to be moved forward by 7-8cm to make room, and it's pretty much already at the practical limit of forward-ness already (with only the radiator being involved!). And then there's the plumbing to deal with...
Using a smaller (and much less effective) side-mounted IC is not an option either, again because there's nowhere to place it, such that it wouldn't interfere with something. MAYBE it would fit on the left hand side, BUT the plumbing would be an absolute nightmare.

Much the same applies for any liquid (or liquefied gas) injection kit. All the components take up very valuable space, and introduce a lot of unnecessary complexity.
Then there is the problem of the liquid tank: place it where? There's no room. In fact, it'll be hard enough to fit the (custom made!) coolant reservoir someplace suitable, let alone another even bigger tank of liquid, or liquefied gas.

On to the control system...
Getting the full benefit out of an intercooler of any kind (including liquid injection "intercooling") requires the fuel delivery limiter to be set according to the charge air density. Not just pressure. The temperature is also very important - in fact, that's the reason for intercooling in the first place.

Now, with an electronic control unit of some description - exerting control over the injection pump delivery by whatever means utilized - this is a trivial thing to do: since you already need to have the pressure sensor (the expensive part) to sense the intake manifold pressure, you only need an extra $1 thermistor in the intake manifold to also measure the temperature. And another $1 worth of circuitry needed for the microcontroller to be able to read the thermistor signal.
Then it's just 1 simple equation (or a lookup table if you wish) to calculate the density from the pressure and temperature. Too easy.

However, I unconditionally hate electronic engine controls, so that approach is absolutely out of the question.

Unfortunately, while the mechanical approach (ALDA compensator on injection pump) can be adjusted to a wide variety of pressure compensation curves as the designer sees fit, it has no amount of compensation whatsoever for the charge air temperature.
The pump itself is internally compensated for the changing ambient temperatures (to some degree at least), but not the charge air temperature, since the pump has no way of sensing that.
Oops.

In practice, it means one of 2 things:
A.) if you're willing to accept heavy exhaust smoke on some occasions - sure, go ahead, adjust the ALDA for the "cruising" boost conditions, ie. with the "low" charge air temperature = high charge air density. After the intercooler becomes heat soaked though, the engine will smoke heavily when floored, until the IC can dissipate the extra "soaked" heat, whereupon it will resume "normal" smoke-free operation.
B.) if you don't want to be driving a mean, soot-belching smokescreen machine, the ALDA needs to be adjusted for the "heat soaked" boost conditions. The problem is, that's essentially the same setting that would be required if you had used no intercooler whatsoever. At this point, why even bother intercooling (unless the long term EGTs are a problem)?

In theory, it would be possible to design and build some crazy compensating contraption, which would use a bimetal strip to sense the temperature, and then bleed off some of the boost signal to reduce the pressure "seen" by the ALDA as the charge air temperature increases.
In practice though, when you reach the point when such things are being seriously considered, it's a good time to pause and reconsider the very important question of "dafuq am I trying to do here?".


TL;DR: intercooling of any kind is just not practical on this bike, and would have very little benefit in practice, considering the other limitations of this design, especially the clutch.


Finally, let me back this up with some hard facts:
VW Golf Mk2.
The 51kW (@4500rpm) 1.6TD engine did not use an intercooler. None.
A long time ago, my family used to own this exact version. Personally, I didn't get to drive it more than several kilometers in total, but it was a blast (for that time, at least, and for a diesel).
That same 1.6D engine was rated 40kW @4800rpm in the non-turbo version, exactly the same as this Ford unit. They used comparable technology. Some minor differences, but none relevant for our purpose at the moment.
In fact, I'm using the Golf Mk2 injector nozzles in the Ford, because the "proper" specified ones were impossible to buy, while the Golf nozzles are the same size, and have nearly identical properties. "Close enough".

Also, that non-intercooled 1.6TD was rated at 133Nm max torque. What a coincidence.

So yeah, not much point to using an intercooler here. Especially since even the "old good" German engineers said no to this, decades before.

[UAofE]

- increased turbo lag (due to extra system volume)

That has been proven untrue many times over.

https://books.google.com/books?id=8bSYN ... &q&f=false

without electronic engine control, it's not possible to utilize it to its full potential.

Tell that to companies that made diesels from the 1960's to the 90's. Not to mention the tens of thousands of turbo/supercharged aircraft developed during WWII.

Therefore, in this particular case, the goal is not to maximize the output power/torque.

My point was to maximize EFFICIENCY. Using less energy to make the same amount of power.

simply because no such clutches/p.plates exist for this engine/gearbox type

Sure there is. You're limiting yourself to that specific make/model of gearbox which you should be searching for disc and plate specs instead.
In addition, you can always machine the flywheel to mount the pressure plate lower to increase clamping force.

Then there is the problem of the liquid tank: place it where?

Thats a major benefit of W/M injection, mount the tank ANYWHERE! It can be any size as small or large as you like.
Unlike a coolant tank, it doesn't have to be mounted at any specific place relative to the engine.
Mount a matching pair behind/in some saddle bags.
A custom rear fender with an integrated tank,
Double compartment fuel tank.
In place of a front fork bag.
etc etc

Getting the full benefit out of an intercooler of any kind (including liquid injection "intercooling") requires the fuel delivery limiter to be set according to the charge air density. Not just pressure.

No, it doesn't. Every single mechanical fuel metering system ever made for turbocharged diesels measures only pressure (aneroid).

Unfortunately, while the mechanical approach (ALDA compensator on injection pump) can be adjusted to a wide variety of pressure compensation curves as the designer sees fit, it has no amount of compensation whatsoever for the charge air temperature.

When an intercooler is designed into the system, density doesn't matter because density is already known when intercooler efficiency is factored in.

The pump itself is internally compensated for the changing ambient temperatures (to some degree at least)

That is incorrect. They may be compensated for FUEL temperature (viscosity), but no mechanical injection pump measures or reacts to air temperature, only air pressure.

A.) if you're willing to accept heavy exhaust smoke on some occasions - sure, go ahead, adjust the ALDA for the "cruising" boost conditions, ie. with the "low" charge air temperature = high charge air density. After the intercooler becomes heat soaked though, the engine will smoke heavily when floored, until the IC can dissipate the extra "soaked" heat, whereupon it will resume "normal" smoke-free operation.

Clearly you've got a LOT to learn about how injection pumps work. Nothing you said there is reality.

considering the other limitations of this design, especially the clutch.

You're liming yourself on that.
Seriously, I found this in 20 seconds of googling: http://www.europerformance.co.uk/pages/ ... uct=161402
http://www.ebay.com/itm/Panther-Paddle- ... 27be919d93
http://www.ebay.com/itm/TORQUE-FAST-ROA ... 0892059423

With their 40% claim, that gets you from 133Nm to 186Nm.

So yeah, not much point to using an intercooler here. Especially since even the "old good" German engineers said no to this, decades before.

Welcome to 2015, some things have been learned in the last 30 years.

[dieseltech]

That has been proven untrue many times over.

Whatever, I'm not going to force the point here, seeing as turbocharging systems are not really my area of expertise.
One thing that is 100% certain though: we own a Golf mk3 1.9TDI (90hp), with the same exact model of turbo I plan to use on the bike. There is a very noticeable lag when abruptly floored, ie. for passing.
I'd imagine that the huge, long-a$$ pipes connecting the intercooler have at least something to do with it.

Tell that to companies that made diesels from the 1960's to the 90's. Not to mention the tens of thousands of turbo/supercharged aircraft developed during WWII.

There's a difference between extracting, say, 99% of the possible benefit, as opposed to, say, only 80%. That is what I meant by "full potential" here.

Also, your point is largely moot, since both the relevant legislation concerning exhaust emissions, as well as the public opinion on the subject, have changed enormously since the times which you have mentioned.
30+ years ago, it was considered perfectly normal for a diesel vehicle to smoke visibly, at least some of the time, ie. when floored.

Good luck with that in this day and age. MOT failures and tickets/fines await diesel vehicles that belch soot for more than a split second at a time.

Already in the late '80s and early '90s, the fueling adjustment on the non-ECU-controlled diesel vehicles was being set very conservatively at the factory, allowing for a wide variation in operating altitude, air filter clogging, component wear, adjustment/measurement tolerances, etc. - all in order to comply with the increasingly strict exhaust emission laws.

The facts remain: with an ECU, it is both theoretically possible, and actually feasible, to allow the engine to operate as close to some arbitrary limit (ie. max smoke emission / exhaust opacity) as possible at all times.

With the mechanical control technology that we're discussing here, some variables can't be measured (let alone be compensated for!) by the control system. Such as the temperature of the charge air reaching the cylinders of a turbocharged engine, to bring up one example.
Therefore, as I mentioned before, you HAVE to either set the fueling more conservatively, if you want the exhaust emissions to be acceptable over a broad range of operating conditions, OR live with the fact that if you set it right at the smoke limit (or just slightly below it), it WILL smoke excessively under some operating conditions - which is perfectly fine for racing use, but NOT for street use.

Street use =/= racing. Different goals, different laws.

Also, in engineering, most of the time there are no absolutes - only compromises.


NOTE: to clarify - I consider ANY visible smoke to be "excessive" on a street vehicle.
This is both out of concern for engine longevity, as well as to avoid any potential problems with the police.

Our law says that a vehicle can be considered technically unsound (and hence subject to stiff penalties) if it "emits excessive amounts of pollution to the environment" or something to that effect. That includes fluid leaks, too.

It doesn't state, however, what constitutes "excessive" pollution - that's up to the police officer's interpretation. Good luck with that.

No visible smoke = no possible violation of the above law.
It's as simple as that. Our cops aren't issued any fancy exhaust gas analyzers - just the standard issue equipment: eyeballs and noses.

My point was to maximize EFFICIENCY. Using less energy to make the same amount of power.

Last time I checked, the turbocharger uses "waste" heat energy from the exhaust stream to extract the power to drive the compressor.
That energy would otherwise be uselessly dissipated into the atmosphere anyway, so it comes with very little "extra" cost.

Also, by now we're pretty much beyond the point where we care about maximizing "efficiency".

Anyway, the efficiency of what?
Conversion of fuel to mechanical energy?
That's not the only thing that matters in a vehicle.

By that metric, the most "efficient" bike would be a small, lightweight one with a 1-cyl diesel from a small generator.
The fuel economy would be excellent indeed. Too bad that the top speed would be outright abysmal, though.
Not very "efficient" for actually moving around, then.

Come to think of it, a "moped" would be actually the most efficient: turn the engine off, use the pedals. 0 liters required per 100km.
Amazing. How is it possible that I didn't come up with this earlier?
I'm off to buy one right now. Maybe even a dozen, or two, for good measure.

Sure there is. You're limiting yourself to that specific make/model of gearbox which you should be searching for disc and plate specs instead.

Sure I do limit myself to this gearbox, because I want to stick with something that works, and which I have based my entire design around.

If I were to use a different gearbox, I might just as well design and build a custom gearbox+swingarm+final drive assembly.
It would save a lot of weight, gain a lot of performance.
And also cost an arm and a leg. And a few kidneys, too. Maybe even a liver as well, or a lung.

No, really, I could buy at least a few used cruisers for the amount it would cost to design and build such an integral unit on a one-off basis.
Absolutely out of the question.

And with this gearbox, the options are very limited:
There is no room for a bigger pressure plate in the bellhousing.
The input shaft probably won't take much more torque than the stock clutch slips at.
The intermediate shaft bearing surface will disintegrate rapidly at such extreme loads (a known "weak point" in these particular Ford gearboxes).
Any "racing" clutch disc will almost invariably have the damper improperly matched to the engine (being intended for the gassers?), resulting in very poor driveability, and possible rapid drivetrain damage.

The list of problems just goes on and on.

Look, with all due respect, I want this bike to be finished in my lifetime. Preferably long before I get too old to be able to enjoy riding it, or die from some horrible disease.
I'd MUCH rather have, and ride, a bike that works - reliably, even if somewhat suboptimally - rather than waste the rest of my life trying to build the "perfect" bike, and never getting to ride it even once, due to it never being completed, ever.

In addition, you can always machine the flywheel to mount the pressure plate lower to increase clamping force.

OK, you clearly don't realize how a modern "constant clamping force" pressure plate works. I'm not even going to bother arguing about this, since I would be just wasting my time.
Also, even if such an approach could in fact work (it won't), it would still be useless, because that would cause the pressure plate fingers to crash into the clutch disc, when the release bearing is actuated to release the clutch.
Even worse, the release bearing might then become jammed on the snout due to the resulting overtravel in the fully extended ("released") position, resulting in an inoperable clutch.

Not to even mention that such remachining would lighten the flywheel a lot, which would cause a bunch of other issues.
Impaired driveability, vibrations (NVH), possibly even a cracked crankshaft... to name a few.

Thats a major benefit of W/M injection, mount the tank ANYWHERE! It can be any size as small or large as you like.

Sure, make it very tiny, so it runs out in a minute or two of boost. Great design for street use, on a touring bike no less.
Bonus points for having made the bike dependent on 2 "fuels" which must both be present to reach full output power. Awesome.

Also, you are excused for maybe not realizing it, since you don't have access to the 3D design files, but there really is no extra room. The engine is huge, the gearbox is very large.
There are LOTS of other components that need to be placed somewhere. Air filter, battery, relay/fusebox, muffler... the list just goes on.

Finally, I don't want any of the extra weight, cost and complexity involved with a liquid injection setup. Not on a street machine / daily driver. Period.

No, it doesn't. Every single mechanical fuel metering system ever made for turbocharged diesels measures only pressure (aneroid).

Which is exactly what I have stated before.
Does nothing to change the fundamental fact: that the DENSITY of charge air is dependent on both the pressure AND temperature, both of which vary, but the latter is NOT being measured.

Ergo, the pump aneroid/diaphragm senses exactly that: only the pressure. NOT the density, which is the most important parameter for controlling the max fueling.

By using the pressure signal as a surrogate for the density, you're invariably making assumptions about the temperature, since those 3 parameters are strictly related by the ideal gas law.
Knowing any 2, the remaining one can be calculated.

When an intercooler is designed into the system, density doesn't matter because density is already known when intercooler efficiency is factored in.

Except that it isn't at all constant. Two words: Heat soak.

Unless you have a fan *constantly* pulling cool ambient air across the intercooler, but that was very uncommon in street applications in the era of aneroid-controlled IPs.

They may be compensated for FUEL temperature (viscosity), but no mechanical injection pump measures or reacts to air temperature, only air pressure.

True. Except that the fuel temperature has a proportional relation to the ambient temperature, which is exactly my point here.

Clearly you've got a LOT to learn about how injection pumps work.

Actually, I have very little more left to learn about them, from a practical standpoint. As far as inline and distributor pumps are concerned, anyway - I don't care about any of that PD or CR nonsense.

Unless you count the really "high-level" stuff, such as designing the drive cam profile to achieve the desired delivery profiles, and selecting the delivery valve characteristics to match the specific injection lines and injectors.
I freely admit that I do not have the (extensive) knowledge required to be able to design those properly. And in actual practice, it doesn't matter even one bit.
That is NEVER going to be relevant unless you have the facilities, and $$$, to actually (re)machine the components with the very high precision required. I do not have either, and likely never will.
Also, unless you are designing a new engine more or less from scratch, there will never be a need to do that, anyway.


Re. the heat soak / smoke issue:
If you had adjusted the ALDA for maximum performance (right at /just under the smoke limit) under normal cruising conditions (= cool intercooler), that is EXACTLY what would be happening if you floor it after a couple minutes of sitting in a bumper-to-bumper traffic jam on a hot summer day.

Of course you will see none of that, if the ALDA setting is more conservative than that. But then you are also not getting the most performance out of your setup, either.

You're liming yourself on that.
Seriously, I found this in 20 seconds of googling: http://www.europerformance.co.uk/pages/ ... uct=161402
http://www.ebay.com/itm/Panther-Paddle- ... 27be919d93
http://www.ebay.com/itm/TORQUE-FAST-ROA ... 0892059423

Paddle (4 puck) clutches. Also known as "on-off clutches".
Garbage.
On a (street) car, that's merely undriveable.
On a bike, pretty much equivalent to a deathwish.

Long story short, it's a classic case of street vs. racing conflict: the on-off characteristics of a paddle clutch are actually beneficial in racing applications (at least, that's what I was told by actual racers), but that is exactly the opposite of the smooth, gradual engagement you want on a street vehicle.

That first clutch you linked to is the only one feasible (non-paddle), but...

Made for use with a standard or mildly modified engine - where torque and engine revs are 20-25% up from standard.

Worthless. My new (OEM-spec) Sachs clutch can easily handle considerably more than +25%, as I've already established from direct measurements.
AND it has the proper damper for this engine.
Why even bother with that? It's much more expensive (+shipping!) for no apparent benefit.

Welcome to 2015, some things have been learned in the last 30 years.

Yes. Unfortunately, most of them irrelevant as far as I'm concerned, or even positively harmful:

Planned obsolescence / designing for warranty period only.
Worthless, fragile, crumbly plastic engine components that should never have been made out of plastic in the first place.
Likewise, aluminium engine parts that should have actually been made of steel/C.I.
ECUs.
Common rail.
EGR.
DPF.
Catalytic converters.
All the other irrelevant electronic garbage omnipresent in modern cars.
"Nanny state" measures.
Paper-thin bodywork.
Very tight interiors in otherwise large cars ("dashboard / upholstery bloat").
etc, etc, etc.

I could go on all night.

IMO, the "golden age" of diesel engine technology peaked at around the '80s/'90s transition.
After the early '90s, it basically all went down the crapper.
Currently, the situation is positively hopeless.

[Tetronator]

Woo buddy, information overload!

Learning loads.

[16VGTIDave]

Informative and entertaining. Thanks!

[dieseltech]

Good news, everyone!

... is what I wish I could say. Sadly, the bad news far outweigh the good, in this case.

So, without further ado, let me get everyone's hopes up... and then proceed to crush them mercilessly, because that's just how life (t)rolls.


For the "good" news, I bring you these:

1. I have plans to build a "semi-proper" workshop, right next to our existing summer house outside of town.
Without a building permit (big $$$), I can build up to approx. 30 sq. meters interior space - far too small for working on cars, but just about enough for what I have in mind, though it will be rather packed.

This would release me from the multiple limitations incurred by (currently) using my friend's "workshop".


2. I've reviewed the situation carefully, and it appears that, rather than trying to cobble something together using the mostly-unmodified Fiesta gearbox - which is suboptimal in a variety of ways - it would be much better to instead cannibalize it for parts, and then design and build a custom gearbox using the existing internals.
And then I can use a bone-stock final drive and rear wheel from an existing (big, heavy) bike - much better and lighter than the previous ideas.
(FYI, chain/belt drive is not quite feasible with this approach - and I despise them anyway)

This is just about within the range of what I consider possible to do, given the limitations I have to work with (or around).

It would involve using the same clutch and pressure plate, and possibly reusing the OEM bellhousing, although it would likely require some modifications. Failing that, the next best alternative is to weld up a custom bellhousing, and send it off elsewhere to have the relevant surfaces machined (impossible for me to fit on my machines - current OR planned).

The actual gearbox housing would have to be welded up and machined, no way around that. It would also neccesarily include swingarm mounts.
I don't think it would be technically feasible to use a stock swingarm, though - most likely custom work will be required.

This approach would also most likely allow the sequential shifter to be built right into the gearbox - that would allow it (the shifter mechanism) to be considerably more compact, and save a good few kilograms in the process, as well as reduce its complexity substantially.

Finally, of course to allow the output shaft to be in the right place to connect to the stock final drive, an intermediate shaft, or - in the worst case - two, will have to be included in the gearbox.

Other advantages?
Almost certainly the whole bike could be lowered a good deal (current design draft is quite tall), while actually increasing the maximum lean angle - since currently the protruding ring gear / differential housing is the major limiting factor with respect to 'hard' ground contact.
In combination with the reduced weight, this would lower the {CoG height * mass} product substantially, reducing the perceived "heavyness".


3. After exhaustively searching for dynamic balancing services in my area, and finding none which fit my acceptability criteria, I got angry, and - after some initial "feasibility testing" - decided to build my own dynamic balancer.

I already have a suitable drive motor: an ancient, but rock-solid, 1/2HP 3-phase unit (from the old, craptastic lathe), made in the GDR (!) - I already performed the required modifications, now it just requires dynamic balancing, itself - hmm, a chicken and egg problem, thankfully I have this one under control - just requires a bit more effort on my part to finish the job.

A good dynamic balancer needs a rock solid base... again, I pondered various possible approaches, including casting epoxy-granite, and decided that a freakin' ~12cm thick natural granite slab (1m long x ~35cm wide) will do the job just fine, thank you very much.
Cheap, easily flat enough, AND very effective!

The drive motor, shaft supports and vibration sensors (regular $1 piezo transducers... tested, work VERY well!) will be mounted on 3cm thick HPL(*) rectangles, which will bolt to a 1m long aluminium "hobby CNC table" extrusion with T-slots in it, itself firmly and semi-permanently bonded to the granite base.

A VFD is needed for the motor - I managed to snag an ancient - 30 year old (!!!) - 1HP, 230V VFD for a piddly ~$35 incl. shipping.
Fully analog, V/f control only - none of this digital "vector control" nonsense, thank you very much!
It's also HUGE - about 6x the volume of an equivalent modern unit.
Really, vector control is actually highly unsuitable for this application - the steady-state loads are very low, but the motor must run very smoothly, and vector control tends to cause increased vibrations, especially at low speeds and low loads. VERY bad!
Of course, modern VFDs can also do V/f. They also cost >$150 for a 1/2HP 230V unit. Used units are only slightly cheaper.
This one works perfectly fine - it's built like a brick outhouse! - and in this application, its large size and low efficiency are pretty much irrelevant.


(*): HPL - high pressure laminate, a wood-derived product that looks and behaves nothing like actual wood (!) - it's essentially paper and epoxy(?) resin pressed together under enormous pressures; much stronger and stiffer than any wood, fairly hard and very durable; at work we throw away literally tons of HPL scrap (all 3cm thick) every month, free for the taking - many pieces being relatively large, and still usable for other purposes.
It's somewhat brittle, machines similarly to hard plastics, and screw threads cut into it are roughly as strong as those cut into aluminium (!!!) - we did some testing, and an M8 8.8 grade bolt screwed into a 3*D thread in HPL will, upon severe overtightening, shear the bolt head clean off, each and every time, rather than stripping out the threads in the HPL. Crazy.
Fun fact: HPL is 1.4x denser than water... it sinks like a brick!


**************************************************************************

And now it's time for the bad news:

Between my increasingly deteriorating health, worsening depression, and other circumstances, I find myself less and less motivated to continue working on this project.

When I started out with this, a few years ago, the idea was to "have fun" building the bike, and then to have even more fun actually riding it.
Unfortunately, the prospect of the latter is growing increasingly distant, whereas the former can, at this point, hardly be described as "fun".

There is very little in the way of "new" challenges remaining to be tackled - with my skills and experience, it's overwhelmingly a case of "what is the most optimal approach to getting this done, given the resources available?", rather than "how do I do this?".
No, before even that, it's mostly just a case of "there's this pile of work, which needs to be done".
In other words, mostly just pure tedium.
Which sounds a lot like work. Work for which I'm not paid anything, and have to supply my own workplace, tools, parts and resources, with the hope of MAYBE being rewarded for it XY years in the future.
That makes my regular 7-to-15 job - which itself is far from 'perfect' - sound like a paradise in comparison.

I have a continuously growing pile of "things I could do, IF only I had the right tools". Sadly, in a lot of these cases, these "right tools" realistically won't be available for the next good few years, at the very least.
That workshop I mentioned at the beginning of this post? It would provide a solution to most of those, BUT we're talking about, at minimum, 6-8 years before I can afford to have it be built and (mostly) fully equipped - and that's not counting other major expenses.
Then there's the issue of location... that's a ~75km round-trip from where I live in the city. Just the travel costs are pretty steep, even if it's a weekends-only thing.
The costs of actually running the workshop do not help things any, either.

Building a house + workshop (scratch that, even JUST a house) closer to the city is, practically speaking, impossible for me. At this rate, it would take around 30 YEARS to gather the funds required - by which time I'm very likely to either be already dead, or in a condition that makes me wish that I were.
Again, never mind the actual operating costs.


On a different note - even if I wanted to, I don't see any way to launch, and maintain, a viable business building diesel-powered bikes (either fully from scratch, or in the form of conversions) - the market is much too small, the barrier to entry very high, and there is a whole trainload of legal BS to put up with (it's mostly about the BS emission control laws, and the BS implications they bring).
Not to even mention the way the economies of scale factor into this.



Now, for the "mercilessly crush everyone's hopes" part, we need to go back to a remark I made about optimization in one of my earlier posts, which brings up a very good point:
What was I hoping to achieve here, anyway? Improve on which aspect(s) compared to the (existing) alternative, which is gasoline power?

... build a bike that uses cheaper (possibly even free) fuel(s), in small(er) quantities no less?
That advantage gets completely eaten up, and then some more, by the cost of the whole undertaking.

... have a bike that will require only minimal maintenance?
The amount of effort that already went into this was easily sufficient to instead keep maintaining/repairing regular, gas-powered bike(s) until the end of my life - and then even do some customizing as well.

... require mostly only cheap, car spare parts?
Good luck with that - the engine I want to use is already long obsolete, and very VERY few remain on the roads. By the time the bike is actually built, and spare parts might be actually needed, they might as well be made of pure unobtainium.

... have good performance?
With a cast-iron diesel? "Good" compared to a car - sure. To a bike - no way, never going to happen.

... have excellent "nevr-stall" low end torque?
It can be approached "close enough" in a gas engine, with the hated electronic total engine control. I'd imagine this is pretty much the case in "modern" bikes already.

... (insert ideological argument here)? Sadly, without a solid economic basis, any of those will rapidly fall flat on their face.
Diesel cars were once so popular in Europe, because they were more reliable, and had lower operating costs than their alternative (gasoline) counterparts. Unfortunately, this appears to no longer be the case with modern cars, but the (new) diesel cars still continue to "stick around" at least due to buyer inertia, if nothing else.

Sure, there are some advantages of diesel power that simply can't be attained with gasoline - the fuel itself not stinking relentlessly, and being very difficult to accidentally ignite, being the first two that come to mind - but then again, the possibility of somehow setting myself on fire while simultaneuosly reeking like a freakin' refinery is pretty much the least of my worries, especially when compared to the predicament I'm currently in.


Well, I think that's about enough for right now.

Effectively, this build has been put on the back burner... of the disconnected old stove rusting in the basement.

As much as this saddens me, at this point I just can't see any way to proceed any further with this, which would be compatible with me retaining any level of whatever sanity that might still remain.

I might consider eventually buying a quality, 2-cyl inline air-cooled diesel (can't say I really like the V-twins - chinese garbage...), and try putting that in an existing bike - IIRC such conversions have already been done - but for right now, even that is outside of the realm of what is actually feasible for me to do.