Flywheel becoming loose (setscrew is used)

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

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

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

Has a nice industrial appearance.

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

Regards, Ken
 

Attachments

  • CLAMPEX-Model.pdf
    51.6 KB · Views: 7
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.

This is pretty close to he Qa industrial couplings . Looks like it would fix any big flywheel . . It’s beyond what can make at this point with the shop lathe down. I’ll look into scaling it and maybe I come up with a bit smaller version. The things I need do not need to be super strong or heavy clamping . In fact I’m considering having them 3 d printed in nylon the clamp screw will probably be 2 mm. I even have a few 2 mm helicoils . The shaft collars I have now can hold even the heaviest brass FW. I have I have a smaller steel FW with the same hub so I can grip that one too

Byron’s
View attachment 138533
And how I used it to secure the flywheel on my beam engine (those are M2 Cap Head Screws) :-
View attachment 138534
Has a nice industrial appearance.

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

Regards, Ken
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.
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
 
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.
https://www.homemodelenginemachinist.com/threads/another-stuart-twin-launch-build-started.31962/
 
Last edited:
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.
https://www.homemodelenginemachinist.com/threads/another-stuart-twin-launch-build-started.31962/
 
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.
View attachment 138533
And how I used it to secure the flywheel on my beam engine (those are M2 Cap Head Screws) :-
View attachment 138534
Has a nice industrial appearance.

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

Regards, Ken


Just re-reading the thread - - would you mind sharing why you chose to use phosphor bronze for your sleeve material?

TIA
 
I chose PB simply because I didn't want mild steel on mild steel for fear of seizing.
On an original (10 times that size which I use industrially) I've had seizures and they are an SOB to get off - I think the sleeve on the originals are a tougher/harder steel than the tapers - but even then they can and do get stuck.
 
Probably a stupid suggestion... (I clamp a brass or copper compression ring - Plumbing style "olive" - onto a steel shaft). But if using "steel on steel", could you prevent seizure by judicial use of copper or Molybdenum or Lithium grease? - Could the reduction of friction from the grease cause slippage? - OR is the clamping force (magnified by the taper) so high it hardly matters about the lower friction of a greased joint?
I think in future I shall be using a split copper Olive, as then it will dismanle easily. The complete ring - distorted under clamping load - is a beggar to remove...
K2
 
Another option to fix something to rotating shaft is the Shaftloc device from SDP/SI.

I used them to fix the timing belt pulleys on an overhead cam engine and they made timing very easy and sure. Also used them on electric starter clutches. They are pricey but very nice.
 
I used a toothed belt with appropriately sized wedge-locked pulleys to add a 700W car alternator to a 500cc Triumph GP motorcycle engine in a Norton Featherbed frame.... For reliable 12V lights, and heated grips... But cost a packet in the 1970s! - No slippage from the wedge lock hubs, subjected to the smooth torque load from the alternator, (or high frequency damped by the belt) and the twin engine pulsations of torque from 850rpm up to 6000rpm. This ran inside an oil bath chain case that also contained the clutch.
K2
 
I previously posted a sketch of the taper lock flywheel hub I used 22 years ago on my Atkinson Differential engine. It never slipped, and never failed to pop loose with the extractor nut on the back end of the taper cone.

I notice the pdf no longer downloads (cockpit trouble?), so I attached here a minor update with a little more information. Crankshaft is straight 1/2 in round, threaded, with a standard 1/2 washer and nut to clamp it against a shoulder. Flywheel bore taper is cut with a hardware store tapered reamer. Taper cone is machined to match. Reasonably easy to make, if you think it might work on one of your projects.
 

Attachments

  • Screenshot 2023-11-15 105440.png
    Screenshot 2023-11-15 105440.png
    318.5 KB · Views: 6
Best way to secure a flywheel is to use a reverse cone....a-la Super Tigre prop driver.
 
I previously posted a sketch of the taper lock flywheel hub I used 22 years ago on my Atkinson Differential engine. It never slipped, and never failed to pop loose with the extractor nut on the back end of the taper cone.

agreed !

the nice thing about tapers is they don't have any slop so they can't vibrate,
and its the vibration that always loosens the set-screw. I use a taper for my
models of aircraft engines, which is standard practice for propellor hubs, but
makes the same sense for flywheels as well.

the other technique I used on a high compression (so high torque vibration) engine
was to key the flywheel and shaft, and use loctite thread *sealant* (not thread *locker*)
on the key, that way it can't vibrate but it can still be disassembled when needed.
 

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