Puting the 6/1 in the garage

[sailawayrb]

I seem to recall estimating that each ounce of weight added to the flywheel rim will create approximately 10 pounds of additional force that the rim will have to handle at 650 RPM.  So adding 8 ounces creates an additional dynamic rim load of 80 pounds.  My point being that one should be careful about adding balance weight to a flywheel of questionable metallurgy.  I am going from memory here so someone should really check my physics/math.

[AdeV]

I seem to recall estimating that each ounce of weight added to the flywheel rim will create approximately 10 pounds of additional force that the rim will have to handle at 650 RPM.  So adding 8 ounces creates an additional dynamic rim load of 80 pounds.  My point being that one should be careful about adding balance weight to a flywheel of questionable metallurgy.  I am going from memory here so someone should really check my physics/math.

If that's likely to be a problem, you could always simply mount a car flywheel on the crank shaft, and add/weld weights to that as required. If you need to balance both sides of the engine, then you'll have to add a second flywheel of course.

[BruceM]

One can certainly make a legitimate and serious case that the Listeroids are unsafe due to their flywheels, and shouldn't be run at all. 

I don't think that minor balancing of the already grossly imbalanced flywheel (external counter weight type Listeroid) to reduce engine pounding will make the safety problem worse. 

The Mr X method requires a soft mount (carpet scraps under temporary wood mount) or a resilient mount to work; it won't be effective on a steel frame mounted engine on concrete. 

I've only mentioned the Mr X method again in this thread due to it's relevance to a guy wanting to put a Listeroid in his garage. It would help with any of the suggested mounting methods, and is something that takes  only a couple hours of time and costs very little.  It's simple and it works, and I'm still very grateful to Mr X and XYZer for presenting it years ago on LEF.

[Halfcrazy]

I appreciate all the comments I did decide to build a lean to on the side of the garage for Put Put she has internal balancing I believe it has the small wheels with circles cut out not spokes it came from CMD. It lived its first 2 years on a wood skid made of 3 8*8's 8ft long planked with 3 inch hemlock planks and it never moved but I will keep the mr x method of balancing in mind I think I am going to use some sort of wood system again maybe 5 8*8's 2 going one way berried in the ground and then 3 the other way on top of them planked over.

[quinnf]

I seem to recall estimating that each ounce of weight added to the flywheel rim will create approximately 10 pounds of additional force that the rim will have to handle at 650 RPM.  So adding 8 ounces creates an additional dynamic rim load of 80 pounds.  My point being that one should be careful about adding balance weight to a flywheel of questionable metallurgy.  I am going from memory here so someone should really check my physics/math.

FWIW, I calculated it as:

Force in gs = ((650 rev/min * 2pi/rev * 1 min/60 sec )^2 * 0.31m )/ 9.8 m/s^2  which equals 147 * g.  So one ounce at the rim should exert a force of 147 ozs. or 9.2 lbs away from the crankshaft.  Not a bad estimate, Bob.  


Quinn

[BruceM]

Quinn, did you weight the flyweel balance weight when you did your "rebuild"?  It's quite a chunk of cast iron, maybe 5 lbs???  That would be about 800 lbs of outward force.

Just trying to get the scale of the forces on the flywheel.

It does make me want some SOM flyweels, but I'm not taking my balancing lead weights off. 

[rbodell]

I sure do thank my lucky stars that my engine came to me perfectly balanced. hardly a ripple in a glass of water and doesn't even need to be fastened down to the floor. The first run it was so smooth that I chalked where it was on the floor and a half hour later it still had not moved from that spot. After all this balancing talk I am absolutely amazed.

[quinnf]

Bruce,

Sorry for my late reply.  Didn't see your post.

Yes, I determined the weight of the balance weights by building a bubble balancer for the flywheels.

I machined a piece of aluminum as follows:



Then I welded a piece of 1/4" steel rod to the center of a piece of steel plate.  Rod has one end sharpened.



Then I placed the aluminum insert on the pointy end of the steel spike . . .



(Now comes the hard part)  Then I hoisted the flywheel over the insert and set it down gently. 



Then I placed a plastic bullseye bubble level, the kind that is used for leveling contertops, on the center of the insert.



Bubble indicates flywheel is way off level.  You'd expect that because of the heavy cast iron balance weight on the flywheel.  By adding lead weights to the rim of the flywheel directly across from the balance weight, eventually the bubble centers and the flywheel is balanced.  The weight of the lead placed on the flywheel rim is equal to the weight of the cast-in counterweight. 

I don't quite recall the weights exactly.  I think they were around 46 and 51 ounces, or around 4 lbs.  At that radius, yes, each flywheel is pulling the crankshaft around as if it had 560 lbs on it.  That's on each end of the crankshaft.  The force on the crank pin at each power stroke is placed 180 degrees to the flywheel balance weights.  That's a heck of a lot of stress on that crankshaft.  I'm amazed how few failures I've heard of.

Early Lister 5/1s had a 1 3/4" crankshaft, and because of failures, Lister increased crankshaft diameter to the present 2" diameter.

Quinn

[BruceM]

Thanks Quinn, I thought you had done a flywheel balance rig.  Nice setup. 

The internal counterbalance seems a wise move, for reduced crank and flywheel stress- I wonder why Lister didn't do that?

[mobile_bob]

my guess is lister found that a single forging for the crank without pads machined for counterweights
resulted in a very strong crank, that could take some flexing for a very long time.

when you start machining flats you can end up "upsetting" the forging and present stresses that would not otherwise there.

thats my story and i am sticking with it!



bob g