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Eric!
After a year or so on a Stewart-Warner, it became apparent to me that it was an awful lot of extra effort for very little benefit.
You must have already decided upon a factor, arbitrarily, and then the wheels are punished until they obey.
The procedure inhibits merely lightening the reciprocating mass to raise a factor, as you must break down the mocked-up bob weights, recalculate, and re-assemble for any changes.
As discussed in the VI article, it will display any concentrated masses in individual wheels, but then so will knife-edges.
Generally, the countermass portion of the wheel is going to be heavier than around the pin, and a 'spoked' flywheel has fewer regions for a pocket of extra mass to occur.
Dynamic experience also told me that the slightest differences in assembly, even when trued within spec, can move apparent heavy spots.
(And I learned the hard way that 'spoked' (cast iron) wheels do not like a lot of dis-assemblies and re-assemblies..)
That's just one of the reasons I always final-assembled the complete crank before considering balancing.
If it fell within a couple of percentage points of what was expected, we saved the customer money, and prevented flywheels from becoming Swiss Cheese.
And Gene!
It is very surprising that your larger forked rod is so nearly the same mass as the male.
Ordinarily, there is a significant difference, making the top proportionally heavier as well (half of a heavy rod should always be more than half of a light one...)
Did you save any photos of the rods themselves?
The female must be quite delicate.
...Cotten
PS: When I finally punched in your numbers, I got about 26%: still enormously low, even for a short stroker. Aluminum pistons will be significantly lighter, right?
That may be all of the 'balancing' you need to raise your factor, without altering the original wheels.
After a year or so on a Stewart-Warner, it became apparent to me that it was an awful lot of extra effort for very little benefit.
You must have already decided upon a factor, arbitrarily, and then the wheels are punished until they obey.
The procedure inhibits merely lightening the reciprocating mass to raise a factor, as you must break down the mocked-up bob weights, recalculate, and re-assemble for any changes.
As discussed in the VI article, it will display any concentrated masses in individual wheels, but then so will knife-edges.
Generally, the countermass portion of the wheel is going to be heavier than around the pin, and a 'spoked' flywheel has fewer regions for a pocket of extra mass to occur.
Dynamic experience also told me that the slightest differences in assembly, even when trued within spec, can move apparent heavy spots.
(And I learned the hard way that 'spoked' (cast iron) wheels do not like a lot of dis-assemblies and re-assemblies..)
That's just one of the reasons I always final-assembled the complete crank before considering balancing.
If it fell within a couple of percentage points of what was expected, we saved the customer money, and prevented flywheels from becoming Swiss Cheese.
And Gene!
It is very surprising that your larger forked rod is so nearly the same mass as the male.
Ordinarily, there is a significant difference, making the top proportionally heavier as well (half of a heavy rod should always be more than half of a light one...)
Did you save any photos of the rods themselves?
The female must be quite delicate.
...Cotten
PS: When I finally punched in your numbers, I got about 26%: still enormously low, even for a short stroker. Aluminum pistons will be significantly lighter, right?
That may be all of the 'balancing' you need to raise your factor, without altering the original wheels.
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