# Flywheel becoming loose (setscrew is used)



## borna (Jan 3, 2013)

Hello all,

I built this engine and trying to start it for the first time. I noticed as the engine wants to start the flywheel become loose. I am holding the flywheel in placed with 4 6-32 setscrews.
The flywheel diameter is 5.5. Any suggestion as how to fix this without too much modification to the flywheel and crankshaft?
 
http://cdn.homemodelenginemachinist.com/attachments/f31/59459d1357071718-my-single-cylinder-engine-002f.jpg

 
This is how the flywheel is connected to the crankshaft.


Thanks
Borna


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## rhankey (Jan 3, 2013)

How about a keyway?


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## aonemarine (Jan 3, 2013)

Lock tite??


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## BobsModels (Jan 3, 2013)

Borna

I agree with the keyway. I have a 1/8 scale Galloway with .250 crank. I have a tapered key in it. I also have set screws one on top of the key and one at 90 degrees. When I broached the keyway in the flywheel I did not
go all the way through and left a taper. I then hand filed a key to thickness and top taper. Put that in and it holds. How well you ask, on 
the governor side I had been taking the flywheel off and on making adjustments. I never tightened the set screws since I was taking it off and on. Well once I got it going I forgot to tighten the set screws. It ran at three differnent shows for about 50 hours before I noticed that one of the set screws was about to fall out.

The goal is to eliminate any motion that can continue to move with each firing cycle. If all is tight and you can move the flywheel with your
hand it is going to come loose.

Good Luck

Bob


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## MachineTom (Jan 3, 2013)

If I see the photo covrrectly, the setscrews are 180° opposed, not a good idea. What happens with that manner of placement if you end up with the flywheel suspended by the 4 rather small screws, as when you tighten them the force directly lifts the flywheel from the shaft, so all forces, and they are rather large from the power stroke to the coast portion, back to the power.

Remove one set of screws and place them about 60° from the other. Those are holes the screws bare against in the shaft not grooves, right.


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## borna (Jan 3, 2013)

Thanks all,
Keyway would be nice. Not sure how to make that. Any special tool I need? I am still beginner. 
How about put a hole all the way through the crankshaft and use pin and maybe screw?

Thanks 
Borna


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## dsage (Jan 3, 2013)

In addition to Machine Tom's comments, try two set screws in each hole. One on top of the other. Tighten the first one well. The second one on top will keep the first for losening. I would also put removable locktite on the outer setscrew(s).

Sage


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## MuellerNick (Jan 4, 2013)

Buy/make a taper lock.


Nick


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## rhankey (Jan 4, 2013)

borna said:


> Thanks all,
> Keyway would be nice. Not sure how to make that. Any special tool I need? I am still beginner.
> How about put a hole all the way through the crankshaft and use pin and maybe screw?
> 
> ...


 
You will need to get a suitably sized broach to cut the keyway in the flywheel.  Broaching is quick and easy.  You will need to come up with a means to press the braoch through the hole.  I use my milling machine vise and some sockets to drive the broaches through the flywheel.  For smaller keyways, it takes 1 or 2 passes. For larger keyways, start with a smaller broach to hog out some of the material, then move up to the desired sized broach, thus taking 3 or 4 passes.  I found and purchased a small Asian made broaching kit which included 4 or 5 broaches and sleeves.  I have had to make a couple of my own sleeves.  The slot can be cut with a keyway cutter or an end cutter.  You can buy pre-made keys, but I have made my own.

Unless the crank is way oversized for the task at hand, I would not run a pin through the crank.  You will weaken the crank too much or the pin is liable to shear.


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## Mainer (Jan 4, 2013)

A second on MachineTom. Put the setscrews 90 degrees apart (or 60 -- doesn't much matter) so the shaft is pressed against the side of the bore in the flywheel, not suspended on the setscrews.


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## thayer (Jan 4, 2013)

I was reading "The Shop Wisdom of Philip Duclos" last night and he shows how to make your own keyway broach, saving a bit of money for something else in the shop.


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## kvom (Jan 4, 2013)

Green loctite (6xx series) is very good, and it will NOT slip.  To remove the flywheel afterwards requires heating with a torch to > 500F.

An easy "key" is to drill or machine a round hole into the boundary at the end of the axle shaft and then press in a piece of round stock to fit.


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## MachineTom (Jan 4, 2013)

This is a broach I made as I didn't have the size I needed. It is a piece of O-1 rod ground to the width needed, then flame hardened and quenched, no temper drawn. This is mounted in the BP with a collet and pushed through with the quill, DOC was .005 of so. I cut it after the photo as you need to keep it as close as possible to the collet to avoid deflection. This is .250 rod 3mm wide keyway. Keep the side straight to guid the cut, put about 3-5° relief on the back, and rake on the front.


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## Philipintexas (Jan 4, 2013)

Sorry, I must have bounced the enter key.


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## Philipintexas (Jan 4, 2013)

I built an IC engine with a 10" flywheel on a 1/2" shaft and could not keep it in place with a key so I used this method. Drill and tap a hole on the circumference of the shaft exactly on the joint, so the hole is half in the shaft and half in the flywheel. Then counter-bore a tight hole for the head of an Allen Bolt. It has never loosened. Obviously, if you remove the bolt you must replace everything in the exact relationship to be able to re-insert the bolt.


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## chucketn (Jan 4, 2013)

Philipintexas said:


> I built an IC engine with a 10" flywheel on a 1/2" shaft and could not keep it in place with a key so I used this method. Drill and tap a hole on the circumference of the shaft exactly on the joint, so the hole is half in the shaft and half in the flywheel. Then counter-bore a tight hole for the head of an Allen Bolt. It has never loosened. Obviously, if you remove the bolt you must replace everything in the exact relationship to be able to re-insert the bolt.


 
Phillip, isn't that called a 'Dutchman'?

Chuck


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## Gedeon Spilett (Jan 4, 2013)

you stopped things just in time !
For such a flywheel and engine setscrews are a nono, otherwise take care when the flywheel will go into orbit &#8230; 
A keyway without lateral play plus a bolt (already present I guess) is the solution.  cut the keyway on the shaft with an end mill, and in the flywheel (if you don&#8217;t have a broach and a press) cut the slot on your lathe transformed in a shaper with a dedicated tool you can grind.
spendid engine, you are almost there


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## MuellerNick (Jan 4, 2013)

To tell the truth, a plain keyway really isn't the best way for alternating loads.
A flywheel stores and releases energy every revolution. As they always do have some play, they will not survive for too long.
If you use a wedge shaped key, things get quite different. The wedge increases the frictional force between shaft and hub. So it is this area that transmits the torque.

If you are using setscrews, it makes no sense to have them in two directions, as they do not increase friction between hub and shaft. More important is to have a flat on the shaft for the setscrew(s) to sit on. Only this way, they can contribute in transmitting torque and they do not tend to dig in that fast.

A cheap way is to drill through the hub and the shaft and drive a rolled pin (C-pin) through. Not very elegant.

If you want/need to transmit torque securely, use a taper lock; a cone with a nut; or a flange with some bolts that press the flywheel against that flange.


Nick


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## borna (Jan 4, 2013)

Hello all,
Thanks so much for all the comments. So I learned my lessons. 
Even though this engine is 1&#8221; bore x 1.5&#8221; stroke with 5.5&#8221; flywheel, I think still produce a good amount of torque. So as I mentioned before, the flywheel was hold in placed with 4 6-32 set screws and as the engine was trying to start, the flywheel was becoming loose. After reading all the comments I came out with a simple solution, but since I am new to engine building, I like to know if this will work and I won't be surprised again by this thing become loose again.




As you can see in the picture, I used two piece clamp-on shaft collar and then drilled 2 holes on the collar and all the way through the hub of the flywheel. Used 6-32 tap so now the collar is attached to the flywheel hub with two 6-32 screws.


It seems to be holding very well. Do you guys think the two 6-32 screws are strong enough and will not break?


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## Gedeon Spilett (Jan 5, 2013)

Hi
Borna : I think the screws between collar and hub would be easily sheared while running your engine...
Muellernick :  I thought that a key would be a good solution without any great modification, namely reboring flywheel. yours explanations are clear and convincing, must not be stingy with the flywheel mounting. 
Cheers


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## borna (Jan 5, 2013)

Thanks Gedeon, To be honest I don't have the right tools to make the key nor I know how.
Maybe the next best thing would be what Nick suggested, using a rolled pin?
by the way how much torque can 6-32 screw handle?

Thanks
Borna


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## kvom (Jan 5, 2013)

I doubt there will be any issues with your current setup, although the screw heads in the end are not attractive.


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## MuellerNick (Jan 5, 2013)

> Maybe the next best thing would be what Nick suggested, using a rolled pin?



What you have now, looks a bit ugly. But it works!
Maybe you turn a cover and slip it over to hide?


Nick


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## borna (Jan 5, 2013)

Thanks guys for the comments. As long as the current setup works, I can always make it nicer by place a cover over it.

Borna


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## Bentwings (Mar 29, 2022)

BobsModels said:


> Borna
> 
> I agree with the keyway. I have a 1/8 scale Galloway with .250 crank. I have a tapered key in it. I also have set screws one on top of the key and one at 90 degrees. When I broached the keyway in the flywheel I did not
> go all the way through and left a taper. I then hand filed a key to thickness and top taper. Put that in and it holds. How well you ask, on
> ...


 Not use a clamping type of attachment so the shaft does not get damaged.you can get different bore and  other  sizes using flexible shaft couplings. By ing this you  get around counter    boring  eparate  shaft collars  I like clamping collars so the shafts don’t get damaged. Keyways are good too you still have to cut the shaft and broach the bores


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## SmithDoor (Mar 29, 2022)

Back 1800's they used taper key. 
Today some engine manufacturers use a tapper shaft and flywheel some morse taper. 

FYI locktie does not work.

Dave 



borna said:


> Hello all,
> 
> I built this engine and trying to start it for the first time. I noticed as the engine wants to start the flywheel become loose. I am holding the flywheel in placed with 4 6-32 setscrews.
> The flywheel diameter is 5.5. Any suggestion as how to fix this without too much modification to the flywheel and crankshaft?
> ...


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## kiwi2 (Mar 30, 2022)

Hi Borna,
               You can use some of the polythene line used in grass trimmers which fits down the threaded hole to stop the screws unthreading. Cut a piece about 2mm long, put it in the hole and tighten the set screw down on it. The screw won't vibrate out. I presume they screw into grooves to prevent the set screws from damaging the shaft. With a bit of plastic between the screw and the shaft you don't need to worry about damage to the shaft. 
Regards,
Alan C.


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## Bentwings (Mar 30, 2022)

SmithDoor said:


> Back 1800's they used taper key.
> Today some engine manufacturers use a tapper shaft and flywheel some morse taper.
> 
> FYI locktie does not work.
> ...


rc model gas engines usually have  taper with woodruff key. The issue is hubs are often aluminum. These expand as thy get hot causing deformation of the taper this then let’s the nut come loose resulting in thrown props among other things. I’ve been through this issue a number of times I’ve made steel hubs with adjustable timing rings holding magnets . By careful design a great deal of the steel weight can be removed without wearing the hub .  Years ago I designed a number of hubs in steel that were within a few grams of aluminum monsters  I YHINK there are still at least three on engines I still have . These have taper and woodruff keys  I made a special puller for these too. In a box in Rc stuff I YHINK . They actually ere easy to service. 
My current steamers have straight shafts only 6 mm do so not easy to make anything but set screw grub screw connections  I have new clamp on shaft couplings coming so bye bye set screws . I hope I can fix the crankshafts I haven’t removed the flywheel yet , later today  I hope the sad part is I knew this would happen as the holes were not straight in causing the flywheel to move until it stuck then the set screw was supposed to hold it . I could maybe grind a flat on the crank for the screw to bear on  but not the eccentric as I didn’t know where it would be finally located . It will be clamped on now and adjustable . I was going to just make a new eccentric with the clamp on feature but I just can’t get to the shop and the boys are very busy. I managed to find the right sizes on the internet to make a coupling assembly . It’s not optimum but I YHINK it will work the single one I found does fit perfectly so I’m in courage’s by that I’ll try a test later today after I verify the timing positions . I agree the lock tite would not have held the fly wheel. 

Byron


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## kf2qd (Mar 30, 2022)

Your collar provides a good amount of friction between the shaft and the collar - now to keep your eye on it and see if it creeps over time. There is an oscilating load on the flywheel, but the torque due to compression is much less than the impulse torque from ignition.


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## Bentwings (Mar 30, 2022)

kf2qd said:


> Your collar provides a good amount of friction between the shaft and the collar - now to keep your eye on it and see if it creeps over time. There is an oscilating load on the flywheel, but the torque due to compression is much less than the impulse torque from ignition.


I have beam type shaft coupler coming for the engine to engine coupling  by the time I’m done I’ll have several flexible vibration absorbing couplers to try. I’ve used all of them in various applications in industry. So far the beam couplers are pretty good. I’ve found they don’t take to high shock loads well but it’s just my experience they are supposed to be ok for this  but when you have machine crashes bets are off . The weakest link looses  hitting a retaining screw with a boring bar doesn’t do them any good either .  I have old ham couplings coming to connect the eccentrics to the crank shafts . I have a single test beam coupling for testing as it was the only one available at the time . It fits perfectly and will have almost no load on it . It mainly a way to couple the eccentric to get crankshaft and provide adjustment . Once everything is back together I’ll begin testing and come up with setting numbers . I’m trying to repair the crankshafts now they won’t be like new but serviceable .

Byron


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## Longboy (Mar 31, 2022)

borna said:


> Hello all,
> After reading all the comments I came out with a simple solution, but since I am new to engine building, I like to know if this will work and I won't be surprised again by this thing become loose again.
> 
> It seems to be holding very well. Do you guys think the two 6-32 screws are strong enough and will not break?
> ...


I like this solution of a clamp collar bolted to the hub. You can up size the hub screws to #8's for some more security.


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## Bentwings (Mar 31, 2022)

Bentwings said:


> I have beam type shaft coupler coming for the engine to engine coupling  by the time I’m done I’ll have several flexible vibration absorbing couplers to try. I’ve used all of them in various applications in industry. So far the beam couplers are pretty good. I’ve found they don’t take to high shock loads well but it’s just my experience they are supposed to be ok for this  but when you have machine crashes bets are off . The weakest link looses  hitting a retaining screw with a boring bar doesn’t do them any good either .  I have old ham couplings coming to connect the eccentrics to the crank shafts . I have a single test beam coupling for testing as it was the only one available at the time . It fits perfectly and will have almost no load on it . It mainly a way to couple the eccentric to get crankshaft and provide adjustment . Once everything is back together I’ll begin testing and come up with setting numbers . I’m trying to repair the crankshafts now they won’t be like new but serviceable .
> 
> Byron


ive got at least 6 iterations of clamping devices to clamp the eccentric and flywheel to the shaft I’ve got one that does both but additional ones are almost a month out I did some rethinking and came up with a coupling instead. These should be here today  I even have some shaft collars that are split clamping both the hub or eccentric to the shaft . Also have flexible couplings to couple the two engines together. Even have a dead level and flat mounting surface so the engine crankshaft bearings are in slight also have a straight line up rod or bar to position the engines dead in alight. This all works well  the crankshafts are longer on one end than the other so I’m almost out of room on the short end. The solution is a split coupler on one end and shaft extension on the other.   I think there are at least 6 items to return to Amazon as they are items I didn’t order or were not what I did order  . I’m think I’m just going to have to take these out to my sons shop and sit down and make exactly what I need. This should be easy. Chilertern has sold a bunch of thes engines so they have to be right but I’m just making thing complicated. I don’t like the set screw attachment and already had issues with it  I see lots of engines with the same features but I don’t hear of issues  maybe I’m just doing something wrong .  I like to have things stay together an run when I need or want . I don’t like constant repairs or adjustments . I can’t complain about the engines there are lots of parts and every one has fit perfectly it just these set screws that have made this less than perfect . I’ll get it done one way or the other. It’s just fighting me all the way . I’ve had countless interruptions and now more estate issues . 

I’ve got one engine complete so I’m goingvto try Irvin very low pressure as it turns over very easily now the piston valve timing worked for a short time but it far from where it should be , I think if it runs as is then I’ll set it up with the adjustable clamp mount I have . From there I can possibly optimize it   I’ll make note as I go 

Byron


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## DKGrimm (Mar 31, 2022)

Had that problem on my Atkinson Differential engine.  I made a tapered bushing to fit in the flywheel.  The bushing is split.  The crankshaft is straight, threaded on the end.  I put an "extractor" nut on the other side of the bushing for easy disassembly.  It has held for twenty years.


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## Bentwings (Mar 31, 2022)

DKGrimm said:


> Had that problem on my Atkinson Differential engine.  I made a tapered bushing to fit in the flywheel.  The bushing is split.  The crankshaft is straight, threaded on the end.  I put an "extractor" nut on the other side of the bushing for easy disassembly.  It has held for twenty years.


clever idea
Byron


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## Bentwings (Mar 31, 2022)

Bentwings said:


> clever idea
> Byron


That’s a good point.  There is a coupler between ebgines but it’s a nice one for vibration and intermittent loads as well as reversing loads . I also have some vibration absorbing ones with urathane spiders . I’ve used these in machine automation but not this small. I got sidetracked today so I’ll get into assembly tomorrow. I also have a number of split collars that can be counter bored . Possibly on both sides I just got them today I’ll sort and do some measuring tomorrow . 

Byron


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## Steamchick (Apr 1, 2022)

On a generator, I attached the rotor to the shaft by using a pair of water tube compression fitting olives and nuts, screwing onto the equivalent tapered connection to the water coupling that I machined on either side of the hub of the rotor... As the generator takes the full and continuous torque of power transmission, from shaft (input) to Rotor (driven), it needs to be adequate, and the double tapered brass olives suit that purpose. It also means that I could assemble the generator with a Silver steel shaft (nice and precise for the ball bearings) and a reamed hole in the centre of the multi-pole PM rotor. Of course, this does not take the pulsating torque of an IC engine, but suits my application. - You can see the brass nut that tightens the olive onto the shaft in these pictures.









K2


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## Bentwings (Apr 1, 2022)

Steamchick said:


> On a generator, I attached the rotor to the shaft by using a pair of water tube compression fitting olives and nuts, screwing onto the equivalent tapered connection to the water coupling that I machined on either side of the hub of the rotor... As the generator takes the full and continuous torque of power transmission, from shaft (input) to Rotor (driven), it needs to be adequate, and the double tapered brass olives suit that purpose. It also means that I could assemble the generator with a Silver steel shaft (nice and precise for the ball bearings) and a reamed hole in the centre of the multi-pole PM rotor. Of course, this does not take the pulsating torque of an IC engine, but suits my application. - You can see the brass nut that tightens the olive onto the shaft in these pictures.
> View attachment 135449
> 
> View attachment 135450
> ...


all of the clamping collars and couplings I have now have at least 1 or 2 3 mm clamp screws . Some clamps are split on one side but essentially clamp all the way around when tightened.  As a set screw or grub screw a single 3 mm screw just is not going to work, and has already been proven I’ve seen others get away with this but I suspect they don’t run the engines long enough or often enough .  I had a tough time getting the flywheel off the crank without causing more damage than what had already occurred. The single stainless screw had a damaged thread. I didn’t want to unscrew it through the brass flywheel so I managed to work it enough that I was able to get the flywheel off then I took my dremel with a very small stone and reached in the bore and ground the end off so I could unscrew the thing .it’s a trick poking a grinding stone in a 6mm bore especially with double vision but it worked ok so the thread hole is preserved fo some unknown purpose later I guess  I just had the by weekly blood test so that’s the interruption for today . Now back to work . I have some split collars that are a bit larger diameter so I’ll see if I get these counter bored  I’ll be able to use a collar on each side of the flywheel so it should stay in place better .  The eccentric only allows for 1 clamp b it should not see large torque and it turns very smoothly. Especially as it is three piece with flat head screws locating the inner flange to the crank bore . I assembled these with a 6 mm pin representing the crank so they did fit nicely . All ther is i the hub to grip with the collar or what ever clamp I use . I thought about remaking them  with a built in clamp but I just don’t think I can reproduce the tolerance and precision they have with our equipment. It’s a fussy thing as it is the finish on them is flawless almost polished . The threaded holes are blind and appear as cut with the cnc rather than done by tap with trimmed blind end . . I’m goingvto revisit them later . 


Byron


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## Bentwings (Apr 2, 2022)

Bentwings said:


> all of the clamping collars and couplings I have now have at least 1 or 2 3 mm clamp screws . Some clamps are split on one side but essentially clamp all the way around when tightened.  As a set screw or grub screw a single 3 mm screw just is not going to work, and has already been proven I’ve seen others get away with this but I suspect they don’t run the engines long enough or often enough .  I had a tough time getting the flywheel off the crank without causing more damage than what had already occurred. The single stainless screw had a damaged thread. I didn’t want to unscrew it through the brass flywheel so I managed to work it enough that I was able to get the flywheel off then I took my dremel with a very small stone and reached in the bore and ground the end off so I could unscrew the thing .it’s a trick poking a grinding stone in a 6mm bore especially with double vision but it worked ok so the thread hole is preserved fo some unknown purpose later I guess  I just had the by weekly blood test so that’s the interruption for today . Now back to work . I have some split collars that are a bit larger diameter so I’ll see if I get these counter bored  I’ll be able to use a collar on each side of the flywheel so it should stay in place better .  The eccentric only allows for 1 clamp b it should not see large torque and it turns very smoothly. Especially as it is three piece with flat head screws locating the inner flange to the crank bore . I assembled these with a 6 mm pin representing the crank so they did fit nicely . All ther is i the hub to grip with the collar or what ever clamp I use . I thought about remaking them  with a built in clamp but I just don’t think I can reproduce the tolerance and precision they have with our equipment. It’s a fussy thing as it is the finish on them is flawless almost polished . The threaded holes are blind and appear as cut with the cnc rather than done by tap with trimmed blind end . . I’m goingvto revisit them later .
> I’ve got a handful of shaft collars and couplings now . I’m just trying to get everything back together. The timing from the two cylinders is radically different but it did run there so I’m leaving it as is for now . My new mounting or clamping will work I YHINK I also ordered som metric end mills specifically to counter bore some collars. These collars are a bit larger in diameter so easier to hold and clamp screws are farther apart so I’ll be able to better use them . Drilled a groove in a finger so I’m working as field medic now . I have a clotting package that’s working  I have to take blood thinners so cuts are not fun I’m not only trying to me a model steam engineer but now learning med tech stuff . I suppose I’ll have to file a safety report for shop injury .
> 
> Byron


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## Vietti (Apr 2, 2022)

Late to the party but I've built a few hit and miss engines and struggled somewhat with flywheels staying tight on the shaft.  Had reasonably good luck with keys made from keystock which comes a few thou oversize, file to a good tapered tight fit.  Make the key as long or longer than the flywheel key way, out to the end of the shaft.  To remove the tight fitting key I tap it as big as possible in a 4 jaw centering chuck.  To remove, use a slide hammer.  I also put in a set screw that hits the key,  drilled at an angle to come out as far into the bore as possible by holding the flywheel at an angle, gets more meat around the set screw.   Works pretty good, sometimes another set screw on the other side of the flywheel.  Use the biggest set screw that makes sense.  YRMV


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## Ozwes007 (Apr 2, 2022)

A piece of round silver steel is a good key. Drill into the shaft and tap the silver steel into it. I would do it between the 2 groves you have put in the shaft. Put a couple of o rings in the groves. On the pulley simply grab a square file or a small warding file on its edge and file the matching key way into the pulley. Broaches are expensive and this is how we did it years ago. Take your time and check constantly for fit. File it under size and work out to what you need to file the width to slowly. A Dutch key is also a good idea.


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## awake (Apr 3, 2022)

Vietti said:


> Late to the party ...


This thread originated more than 9 years ago, so quite a few folks are late to this particular party!


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## Bentwings (Apr 4, 2022)

awake said:


> This thread originated more than 9 years ago, so quite a few folks are late to this particular party!


 After I got home yesterday I began searching for more information on piston valve timing . I can now get the power piston exact location. TDC or BDC . So moving over I can measure the piston port valve position with the “ very near calipers”  in relation to the i power piston , carting this a step further I just got the new tapered 1/4” 40 TPI ME  die. So I can thread the 1/4” pipe with taper threads then chase them with the straight die. I know this is not perfect but it gives me the ability to make a 40 TPI screw that will screw into the exhaust port right over the piston valve . Effectively giving me exact position in relation to the power piston . So after viewing a number of videos , some consider these small steamers not worth the time to fuss with the port timing. The power piston does have clearance at both ends of its stroke for a cushion effect . This seems to eliminate the “knock”?that some larger engines seem to have . I’m assuming it’s a looseness in bearings. M little steamer has pretty snug bearings especially with oil in them . 
It’s said the piston valve is better than the slide valve as steam does not push directly on it. One video noted the “wet steam” or “ vapor steam” that may have some oils in it.  So that’s good . I’ll have some oiling anyway . I won’t get into real steam for a while until my boiler is done . At that point I’ll see what needs to be done as far as oiling . I do have an oiler available.  As well as air compressor oiling . 

With this I’m rethinking the timing issues. 

Any comments would be appreciated . 

I hope I’m not over thinking this . One of the race car competitors I ran into at the car show came ver and we re acquainted. 
He said of all the racers I was type one that was toughest to beat. Quite a compliment. I bought us lunch. 


Well another interruption . Another surprise doc visit . I should be thankful I guess the health people really take care of their people I changed the bandage on my hand to a skin colored one. Hope she doesn’t notice it. I tried to drill a hole in my finger. Fast reactions only allowed a small flap of skin to be peeled out .

Byron


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## Bentwings (Apr 5, 2022)

Bentwings said:


> After I got home yesterday I began searching for more information on piston valve timing . I can now get the power piston exact location. TDC or BDC . So moving over I can measure the piston port valve position with the “ very near calipers”  in relation to the i power piston , carting this a step further I just got the new tapered 1/4” 40 TPI ME  die. So I can thread the 1/4” pipe with taper threads then chase them with the straight die. I know this is not perfect but it gives me the ability to make a 40 TPI screw that will screw into the exhaust port right over the piston valve . Effectively giving me exact position in relation to the power piston . So after viewing a number of videos , some consider these small steamers not worth the time to fuss with the port timing. The power piston does have clearance at both ends of its stroke for a cushion effect . This seems to eliminate the “knock”?that some larger engines seem to have . I’m assuming it’s a looseness in bearings. M little steamer has pretty snug bearings especially with oil in them .
> It’s said the piston valve is better than the slide valve as steam does not push directly on it. One video noted the “wet steam” or “ vapor steam” that may have some oils in it.  So that’s good . I’ll have some oiling anyway . I won’t get into real steam for a while until my boiler is done . At that point I’ll see what needs to be done as far as oiling . I do have an oiler available.  As well as air compressor oiling .
> 
> With this I’m rethinking the timing issues.
> ...


thats a clever method of connecting shafts I’ll have to remember that one. 
Byron


----------



## Bentwings (Apr 5, 2022)

Bentwings said:


> thats a clever method of connecting shafts I’ll have to remember that one.
> Byron



I’ll be watching for any movement . Fortunately I think I’ll now have a quick easy way to check on the eccentric position I’m not sure just how the main flywheel mounting is going to shake out I could use a shaft extension as ll have a outside shaft support with bearing in it once I get everything up and running I’ll be better able to see what I need. 
Byron


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## Bentwings (Apr 6, 2022)

Bentwings said:


> I’ll be watching for any movement . Fortunately I think I’ll now have a quick easy way to check on the eccentric position I’m not sure just how the main flywheel mounting is going to shake out I could use a shaft extension as ll have a outside shaft support with bearing in it once I get everything up and running I’ll be better able to see what I need.
> Byron


i have some collars that I use as a doubler against the clamp collar so it will be really  hard for the “ working collar to move I didn’t want to give up the shaft space but better that than have something move . I finally got the flywheel bores cleaned out by rolling a piece of fine Emory paper around a drill bit and using it like a hone I think the thread hole was bent over as that was the tight spot I polished the shaft but I can’t see any reduction in size. Just nice and smooth


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## Bentwings (Apr 6, 2022)

Bentwings said:


> After I got home yesterday I began searching for more information on piston valve timing . I can now get the power piston exact location. TDC or BDC . So moving over I can measure the piston port valve position with the “ very near calipers”  in relation to the i power piston , carting this a step further I just got the new tapered 1/4” 40 TPI ME  die. So I can thread the 1/4” pipe with taper threads then chase them with the straight die. I know this is not perfect but it gives me the ability to make a 40 TPI screw that will screw into the exhaust port right over the piston valve . Effectively giving me exact position in relation to the power piston . So after viewing a number of videos , some consider these small steamers not worth the time to fuss with the port timing. The power piston does have clearance at both ends of its stroke for a cushion effect . This seems to eliminate the “knock”?that some larger engines seem to have . I’m assuming it’s a looseness in bearings. M little steamer has pretty snug bearings especially with oil in them .
> It’s said the piston valve is better than the slide valve as steam does not push directly on it. One video noted the “wet steam” or “ vapor steam” that may have some oils in it.  So that’s good . I’ll have some oiling anyway . I won’t get into real steam for a while until my boiler is done . At that point I’ll see what needs to be done as far as oiling . I do have an oiler available.  As well as air compressor oiling .
> 
> With this I’m rethinking the timing issues.
> ...


M sitting here trying to get tiny things lined up and my kitty jumped on the table. Then she grabbed a small bag that had a shaft coupler in it that just arrived . She doe not play with anything hard let alone my stuff . But sh knocked iron the floor the grabbed the bag and took off.  Cats are great at causing trouble then hightailing it out ofvthe area like nothing happened  well it’s gone somewhere. Most likely under the bed.  I’ll take a walk. Yup there it is an arms length under the bed.  She is now curled up in her kitty carrier like nothing happened . At least I found t she could have smacked it under the fridge 

Byron


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## Mike Ginn (Apr 7, 2022)

Re fixing a flywheel.  I use the Westbury method which just works.  I'm sure it must have been described in the Forum at some time.  I first came across this method in the Model Engineering Mag years ago as described by Westbury.  I don't know if the method is original or falls into the category of "obvious".  Attached is my use of the method along with the extractor.
Mike


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## SmithDoor (Apr 7, 2022)

It is a great way too.

I use on air compressor flywheels.  It works great just like tapper shaft.
I like mores tapper as you buy reamer off shelf for ID and test plug is on shelf too (aka morse tapper drill bit).

Dave



Mike Ginn said:


> Re fixing a flywheel.  I use the Westbury method which just works.  I'm sure it must have been described in the Forum at some time.  I first came across this method in the Model Engineering Mag years ago as described by Westbury.  I don't know if the method is original or falls into the category of "obvious".  Attached is my use of the method along with the extractor.
> Mike
> View attachment 135560


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## Bentwings (Apr 7, 2022)

It is a great way too.



I’ve got a pile of shaft collars and couplers now I just got a jaw coupling for the larger joint flywheel it’s got a slightly larger hub but I have a coupling that will work  it should be eas to remove the plastic spider in these small couplings make them hard to separate I could make a simple puller separated at some point but I have enough to do now. Also got rod stock for new piston connecting rods . I’ll add abou 1-2 threads on each end so there is more room for the jam nuts .


Byron


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## Bentwings (Apr 7, 2022)

Bentwings said:


> It is a great way too.
> 
> 
> 
> ...


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## SmithDoor (Apr 7, 2022)

Morse tapper is about for locking on crack shaft. Brown and Sharp is a good tapper too but most do not have that reamer. 
Boat prop use #2 Morse too. 

Dave 



Bentwings said:


> It is a great way too.
> 
> 
> 
> ...


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## Steamchick (Apr 8, 2022)

I first used proprietary taper-lock bushes in the 1970s, to fit an alternator drive pulley onto an old motorcycle crankshaft in place of the original keyed pulley. (Not having machines or tools to re-create the keyway on the new pulley size). It worked fine, as have tapers since tapered wooden pegs and tapered holes were first carved and used many thousands of years ago... Some of the OLD technology was very good! I have seen a split-Tapered plug in a wooden wind-mill (many centuries old) that secured a large "gear" (Pegged wheel) to a shaft. Occasionally, the current miller would give it a tap to be sure it was secure, as evidenced by the lump hammer close by, and recent marks on the wood plug. 
Enjoy!
K2


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## Bentwings (Apr 8, 2022)

Mike Ginn said:


> Re fixing a flywheel.  I use the Westbury method which just works.  I'm sure it must have been described in the Forum at some time.  I first came across this method in the Model Engineering Mag years ago as described by Westbury.  I don't know if the method is original or falls into the category of "obvious".  Attached is my use of the method along with the extractor.
> Mike
> View attachment 135560


Finally getting out to the shoo today. I hope I can finish all the little tweaks I want to make . I’ve got couplers and shaft collar that just need minor machine work mostly lathe work. I’m going to  have to cut reliefs for cap screws in the larger shaft collars and couplers but I think I make a simple round holding fixture or just use a small end mill . 
I managed to get the chuck off the Mickey Mouse drill press  I YHINK I’ll try and reinstall it with the blue locctite an put a weight on the handle to put pressure on it while the loc tite sets up  

Byron


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## DKGrimm (Apr 9, 2022)

SmithDoor said:


> Morse tapper is about for locking on crack shaft. Brown and Sharp is a good tapper too but most do not have that reamer.
> Boat prop use #2 Morse too.


This taper lock bushing really works well.  My version is shown in the drawing attached to my March 31 post, but the taper is not specified.  I used 3.5 degrees (7 degrees included angle) that I matched up by boring the flywheel taper and turning the bushing taper without moving the compound setup.  You can see the extractor nut on the big end of the taper bushing.


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## GailInNM (Apr 9, 2022)

Byron,
RE: your kitty saga.
About 25 years ago I was manufacturing fully machined ready to assemble steam engine kits that had about 4 dozen 0-80 and 2-56 screws. One day I received a brief note from a customer that told it all in four short lines.
"Dining room table"
"Shag carpet"
"Large cat."
"Please send complete set of screws"

Gail


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## Mike Ginn (Apr 9, 2022)

Hi DKG
I seemed to have missed your post!  Yes it is vital to machine at the same setting - usually by cutting the collet with the lathe in reverse and cutting on the far side.

Interesting that Steamchick (K2) mentions the wind-mill gear being secured with a similar system.  I now recall seeing it is use but it didn't really register (in my mind) at the time.

Interesting how we can all learn from the techniques of the past!

Mike


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## SmithDoor (Apr 9, 2022)

Bentwings said:


> Finally getting out to the shoo today. I hope I can finish all the little tweaks I want to make . I’ve got couplers and shaft collar that just need minor machine work mostly lathe work. I’m going to  have to cut reliefs for cap screws in the larger shaft collars and couplers but I think I make a simple round holding fixture or just use a small end mill .
> I managed to get the chuck off the Mickey Mouse drill press  I YHINK I’ll try and reinstall it with the blue locctite an put a weight on the handle to put pressure on it while the loc tite sets up
> 
> Byron


I like see a rea


GailInNM said:


> Byron,
> RE: your kitty saga.
> About 25 years ago I was manufacturing fully machined ready to assemble steam engine kits that had about 4 dozen 0-80 and 2-56 screws. One day I received a brief note from a customer that told it all in four short lines.
> "Dining room table"
> ...


I never received the dining room table , Shag carpet or Large cat. But faxs missing screw , the wrong size sometimes a photo of some one else bolts (wrong color).  I can see some losing 0-80 or 2-56. My shipping was 1/2" and larger bolts bolts in 5 gal buckets.  
How do you lose that. I try everything including taking photos.  
It was alway my error. I just add to price . 
Metal building companies had same problem too they shipped by 4,000 pound pellet of bolts. 

It is problem for any supplying screws and bolts. 

Dave


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## Bentwings (Apr 10, 2022)

SmithDoor said:


> I like see a rea
> 
> I never received the dining room table , Shag carpet or Large cat. But faxs missing screw , the wrong size sometimes a photo of some one else bolts (wrong color).  I can see some losing 0-80 or 2-56. My shipping was 1/2" and larger bolts bolts in 5 gal buckets.
> How do you lose that. I try everything including taking photos.
> ...


no missing screws just tiny hard to hold screws we drilled and tapped holes bored counter bores drilled plastic spiders and made new parts out of other sizes today had 32 pound Main Coon cat for bed warmer last night 10 pound tabby watched so nothing funny went on. Black and white patches the cat ruler guarded all of us. 
We got a lot done today so I can now finish assembly not everything the way I wanted but some parts did not machine well or could not be held securely . I think I have what I need to get back in business.  We threaded some brass stock with the 1/4” 40 TPI ME tap and die and made better holders for the small round dies also drilled ad tapped a bunch of brass nuts so I have jam nuts then made half a dozen 1/4 40 TPI brass plugs. I have been unable to purchase these so I cut them from hex stock snd threaded them fit perfectly. Have temporary mounting plate for the throttle valve. I’ll make a better one later. We didn’t have any suitable stock . I ordered a piece of stock for shaft extension in case I need it . I’m going to make plans for a step up gear box timing belt driven to drive the generator I got from PM research. So it was a good day.  I repaired the busted parting tool. It only has taper on one side so it must be a cheap piece . I put an equalizing shim in the holder and honed the cutting edges it works now . We made a couple spacers to hold the small dies in the holder better much easier to use now. 
Byron


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## Bentwings (Apr 11, 2022)

Bentwings said:


> no missing screws just tiny hard to hold screws we drilled and tapped holes bored counter bores drilled plastic spiders and made new parts out of other sizes today had 32 pound Main Coon cat for bed warmer last night 10 pound tabby watched so nothing funny went on. Black and white patches the cat ruler guarded all of us.
> We got a lot done today so I can now finish assembly not everything the way I wanted but some parts did not machine well or could not be held securely . I think I have what I need to get back in business.  We threaded some brass stock with the 1/4” 40 TPI ME tap and die and made better holders for the small round dies also drilled ad tapped a bunch of brass nuts so I have jam nuts then made half a dozen 1/4 40 TPI brass plugs. I have been unable to purchase these so I cut them from hex stock snd threaded them fit perfectly. Have temporary mounting plate for the throttle valve. I’ll make a better one later. We didn’t have any suitable stock . I ordered a piece of stock for shaft extension in case I need it . I’m going to make plans for a step up gear box timing belt driven to drive the generator I got from PM research. So it was a good day.  I repaired the busted parting tool. It only has taper on one side so it must be a cheap piece . I put an equalizing shim in the holder and honed the cutting edges it works now . We made a couple spacers to hold the small dies in the holder better much easier to use now.
> Byron





Bentwings said:


> no missing screws just tiny hard to hold screws we drilled and tapped holes bored counter bores drilled plastic spiders and made new parts out of other sizes today had 32 pound Main Coon cat for bed warmer last night 10 pound tabby watched so nothing funny went on. Black and white patches the cat ruler guarded all of us.
> We got a lot done today so I can now finish assembly not everything the way I wanted but some parts did not machine well or could not be held securely . I think I have what I need to get back in business.  We threaded some brass stock with the 1/4” 40 TPI ME tap and die and made better holders for the small round dies also drilled ad tapped a bunch of brass nuts so I have jam nuts then made half a dozen 1/4 40 TPI brass plugs. I have been unable to purchase these so I cut them from hex stock snd threaded them fit perfectly. Have temporary mounting plate for the throttle valve. I’ll make a better one later. We didn’t have any suitable stock . I ordered a piece of stock for shaft extension in case I need it . I’m going to make plans for a step up gear box timing belt driven to drive the generator I got from PM research. So it was a good day.  I repaired the busted parting tool. It only has taper on one side so it must be a cheap piece . I put an equalizing shim in the holder and honed the cutting edges it works now . We made a couple spacers to hold the small dies in the holder better much easier to use now.
> Byron


im right in the middle of sorting the reworked parts out. I hope we got every thing .
The first thing I did at the shop was drop a small old ham coupling urathane spider on the floor . These are pink so very visible you can’t believe how far it rolled. It was like a ball bearing on an aircraft carrier deck one of the guys stepped on it is how we found it . 
Byron


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## Bentwings (Apr 11, 2022)

Bentwings said:


> im right in the middle of sorting the reworked parts out. I hope we got every thing .
> The first thing I did at the shop was drop a small old ham coupling urathane spider on the floor . These are pink so very visible you can’t believe how far it rolled. It was like a ball bearing on an aircraft carrier deck one of the guys stepped on it is how we found it .
> Byron


I made an interesting discovery last night . I discovered that certain shaft collars fit inside the rings on the lovejoy couplers. All I need to do is drill and tap locking screws and I’ll have a short coupling that grips the eccentric as well as the crankshaft . Saves a lot of tricky work . Plus gives the adjustment I wanted . It’s not as easy as wanted but other than testing it should work fine and be secure. 
 I’ll work more tonight  I hav a virtual doc visit tomorrow  always something  almost done with estate issues .

I heated the drill chuck as hot as my little torch could get it , about 450 deg F then pushed the spindl into the chuck and smacked the handle .  I haven’t tried it but this is what was said to do to install the jacobs.  I’ll try a 3/8” drill later . Everything got out of order taking it out to the shop last week end so I’m re organizing today  we made half a dozen 1/4” 40 TPI ME blind plugs that I needed plus I drilled and tapped some of the brass nuts so I can have lock nuts where needed. I have a bag of fiber sealing washers too . Working on a gearbox for driving the PMR research generator model now too . It’s not a very powerful generator but I YHINK I may be enough to drive a couple LED lights  for the engine area. 
Byron


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## Bentwings (Apr 12, 2022)

Bentwings said:


> I made an interesting discovery last night . I discovered that certain shaft collars fit inside the rings on the lovejoy couplers. All I need to do is drill and tap locking screws and I’ll have a short coupling that grips the eccentric as well as the crankshaft . Saves a lot of tricky work . Plus gives the adjustment I wanted . It’s not as easy as wanted but other than testing it should work fine and be secure.
> I’ll work more tonight  I hav a virtual doc visit tomorrow  always something  almost done with estate issues .
> 
> I heated the drill chuck as hot as my little torch could get it , about 450 deg F then pushed the spindl into the chuck and smacked the handle .  I haven’t tried it but this is what was said to do to install the jacobs.  I’ll try a 3/8” drill later . Everything got out of order taking it out to the shop last week end so I’m re organizing today  we made half a dozen 1/4” 40 TPI ME blind plugs that I needed plus I drilled and tapped some of the brass nuts so I can have lock nuts where needed. I have a bag of fiber sealing washers too . Working on a gearbox for driving the PMR research generator model now too . It’s not a very powerful generator but I YHINK I may be enough to drive a couple LED lights  for the engine area.
> Byron


Speaking of bolts I was watching Star Trek DS9 Quark has a bunch of “ stem bolts” he always trying to pedal supposedly worth a fortune in gold pressed Latium . What the heck are thes and what are they used for? 

Buron


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## Bentwings (Apr 16, 2022)

Bentwings said:


> Speaking of bolts I was watching Star Trek DS9 Quark has a bunch of “ stem bolts” he always trying to pedal supposedly worth a fortune in gold pressed Latium . What the heck are thes and what are they used for?
> 
> Buron is added 5 layers of paper to the mating surfaces if the small shaft collars so when I drill them to shaft size there will be compression space to provide clamp force . Probably a not necessary thing I could have just added a strip of 10000 grit sandpaper between the coupler bore an shaft . I’ll drill them it shortly also received a piece of capillary quality stainless steel tubing for shaft extension. It fits extremely close on all the crank shafts I’ll have to drill out collars or couplers as necessary. I could probably just split it with dremel fine saw blade and clamp it. Or just super glue it to the shafts.  I’ll experiment a little I YHINK I have some 6 mm stainless round stock that the new tube just barely slide on.
> Today and tomorrow I’m goingvto concentrate on re assembly ofvthe engines.  I think I have every modified part I need for now.  Nasty weather again. Rain wind sleet cold.  Not going anywhere.
> Byron


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## Bentwings (Apr 19, 2022)

In my ongoing attempt to learn more about piston valve timing. I’ve read a number of articles and watched videos 

Each start with the flywheel and power piston at TDC . Perfect I understand that from hot rod world . We used degrees balancers 
and timing rings to establish this and set ignition timing snd cam timing . So nothing new there . I really don’t want to make perms too marks on these flywheels yet. So I looked for some kind of sticky backed Mylar tape measures I could just stick on the make calculation of distance based on flywheel diameter . I YHINK that will work as far as finding the TDC I can then mark it and proceed to note graduations it may not be dead perfect but pretty close , certainly better than eyebal “ about” adjustments . So I ordered this and I’ll apply some . I can then not exact position of the piston valve in degrees .  I can then make adjustments as needed. The videos and texts seemed to have wildly different  approaches the so called “ lead varies from a lot to not much with compressed air  it should be pretty consistent across my engines but when steam comes it can vary because of the increased energy in steam. A little for a long way . The ports are pretty small on this engine  and you can’t see them when the engines are assembled. As in the videos and texts it will be different but adjustments can be made in measured amounts  either way . I can see many pages of notes and maybe a video later .  I’ve got one last interruption today then I can get back to fun . This has been a difficult hobby but any would be . Jumping into scale Rc warbirds or streetrods 
Byron would be difficult too , to a new comer.


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## Bentwings (Jul 16, 2022)

Bentwings said:


> thats a clever method of connecting shafts I’ll have to remember that one.
> Byron


I have to explode the home made taper 1/4 40 me tube or pipe will need to be drilled to 6mm in my case for the shaft essentially make a wdvtaper hub with the taper compression provided by forcing the thread taper to compress on the shaft wd40 hubs usually have built in jack screws to remove them . The next option is to use 1/16 pipe taper the same way , again I have to explore sizes . I thought that it would be possible to add a brass tube sleeve inside the hub to make up more correct diameters.   Currently I use counter bores shaft collars that grip the hub the best are double split  I hand split a couple then heli oiled the 4 mm thread it’s not the strongest but it does work  currently I’m working on a designed double split hub for the eccentrics  this gets a little complicated as the removable half of the hub needs to be made as a connecting rod cap . I may be able to salvage a small shaft collar and use 2 mm socket head screws . But this is getting pretty small  I don’t need a lot of force to hold the eccentric hubs but there is not much shaft space . They are not hard pard parts to make but just small . I may contact a local 3 d metal printer and see if they could just print half dozen hubs . According to what I was told he can print so am2 thread might only have to be chased to debut it  if cost is good that would be the fix . I have a classic car that I’m goingvto sell so I just may turn it over into a 3 d metal printer of my own . Technically it would be safer than me wandering about in the shop . They also can print plastic with nozzle change and temp adjustment .  I don’t know how much electric power they take but I do ave 220 available. I now have my solid works connected to my tv so I can see the screen better   I’m working an hour a day to relearn the SW. it’s coming back slowly . Looking atvthe mess tat the little engine crash caused. Ifvyhe crankshaft had been polished or cut about .003 under size where the set screws located the mess would have been avoided altogether since the lathe is down I can’t even do that myself as a repair.


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## Ken I (Jul 17, 2022)

Here's a model of an industrial "Clampex" coupling I made - mostly just to see if it would work :-





It worked fine - nut was a prototype to test torque - came in at 7.5 ft.lbs.




And how I used it to secure the flywheel on my beam engine (those are M2 Cap Head Screws) :-




Has a nice industrial appearance.

Otherwise an awful lot more work than a simple grub screw WTH knock yourself out.

Regards, Ken


----------



## Bentwings (Jul 17, 2022)

Ken I said:


> Here's a model of an industrial "Clampex" coupling I made - mostly just to see if it would work :-
> View attachment 138532
> 
> It worked fine - nut was a prototype to test torque - came in at 7.5 ft.lbs.
> ...





Bentwings said:


> In my ongoing attempt to learn more about piston valve timing. I’ve read a number of articles and watched videos
> 
> Each start with the flywheel and power piston at TDC . Perfect I understand that from hot rod world . We used degrees balancers
> and timing rings to establish this and set ignition timing snd cam timing . So nothing new there . I really don’t want to make perms too marks on these flywheels yet. So I looked for some kind of sticky backed Mylar tape measures I could just stick on the make calculation of distance based on flywheel diameter . I YHINK that will work as far as finding the TDC I can then mark it and proceed to note graduations it may not be dead perfect but pretty close , certainly better than eyebal “ about” adjustments . So I ordered this and I’ll apply some . I can then not exact position of the piston valve in degrees .  I can then make adjustments as needed. The videos and texts seemed to have wildly different  approaches the so called “ lead varies from a lot to not much with compressed air  it should be pretty consistent across my engines but when steam comes it can vary because of the increased energy in steam. A little for a long way . The ports are pretty small on this engine  and you can’t see them when the engines are assembled. As in the videos and texts it will be different but adjustments can be made in measured amounts  either way . I can see many pages of notes and maybe a video later .  I’ve got one last interruption today then I can get back to fun . This has been a difficult hobby but any would be . Jumping into scale Rc warbirds or streetrods
> Byron would be difficult too , to a new comer.





Bentwings said:


> I have to explode the home made taper 1/4 40 me tube or pipe will need to be drilled to 6mm in my case for the shaft essentially make a wdvtaper hub with the taper compression provided by forcing the thread taper to compress on the shaft wd40 hubs usually have built in jack screws to remove them . The next option is to use 1/16 pipe taper the same way , again I have to explore sizes . I thought that it would be possible to add a brass tube sleeve inside the hub to make up more correct diameters.   Currently I use counter bores shaft collars that grip the hub the best are double split  I hand split a couple then heli oiled the 4 mm thread it’s not the strongest but it does work  currently I’m working on a designed double split hub for the eccentrics  this gets a little complicated as the removable half of the hub needs to be made as a connecting rod cap . I may be able to salvage a small shaft collar and use 2 mm socket head screws . But this is getting pretty small  I don’t need a lot of force to hold the eccentric hubs but there is not much shaft space . They are not hard pard parts to make but just small . I may contact a local 3 d metal printer and see if they could just print half dozen hubs . According to what I was told he can print so am2 thread might only have to be chased to debut it  if cost is good that would be the fix . I have a classic car that I’m goingvto sell so I just may turn it over into a 3 d metal printer of my own . Technically it would be safer than me wandering about in the shop . They also can print plastic with nozzle change and temp adjustment .  I don’t know how much electric power they take but I do ave 220 available. I now have my solid works connected to my tv so I can see the screen better   I’m working an hour a day to relearn the SW. it’s coming back slowly . Looking atvthe mess tat the little engine crash caused. Ifvyhe crankshaft had been polished or cut about .003 under size where the set screws located the mess would have been avoided altogether since the lathe is down I can’t even do that myself as a repair.


Bagg


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## David Shealey (Jul 18, 2022)

10+ years machinist/tool and die maker, then over 40 years machine design engineer, I learned very early on to hate set screws on rotating shafts with a blinding purple passion!  I used many different shaft locking devices over the decades, and absolutely refused to put a set screw on a shaft that was rotating. I did design changes in my Stuart two cyl launch engine to avoid set screws.





						Another Stuart Twin Launch build started.
					

My dad got a Stuart Twin Launch kit as a retirement gift when he retired in 1980.  He put together a small shop over a couple years, and barely started the work on this, but he passed away in 1984.  I got the kit about 4 years ago planning to finish it one day.   Well, I have now started on it...




					www.homemodelenginemachinist.com


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## Bentwings (Jul 22, 2022)

David Shealey said:


> 10+ years machinist/tool and die maker, then over 40 years machine design engineer, I learned very early on to hate set screws on rotating shafts with a blinding purple passion!  I used many different shaft locking devices over the decades, and absolutely
> 
> 
> Glad somebody agrees with me refused to put a set screw on a shaft that was rotating. I did design changes in my Stuart two cyl launch engine to avoid set screws.
> ...


----------

