Lynn,
Thanks, I have spun up the rotor in a lathe and filled the rotor with coolant from a spray bottle, being careful not to spill any and then weighing the remainder and comparing it to the original weight (similar system to what you suggest). I went the extra mile and then adjusted the weight by comparing it to oil weight of the same volume.
I did speak to Richard Sohn at the time but at that stage he wasn't to concerned with balancing to that extent with his demonstrator.
It has also been suggested that the apex seal and springs be excluded as their weight is borne by the rotor housing.
Then again I've had people argue against those suggestions.
I thought any out of balance might exacerbate the negative torque pulses, but your saying because their so large it's not such a concern - which puts my mind to rest.
I do like your suggestion of 'reverse engineering' the balancing process, I think I will discuss that with a professional balancer.
George (down under)
Lynn,
With balancing my single rotor, what would you suggest that I allow ( percentage wise) for oil weight in the rotor - it was suggested to me that I should allow full rotor oil weight.
This discussion suggests otherwise.
George ( down under)
I think that is what we are happy with. I assume the rotor spining on its own axis and orbiting will do two things in various degrees. The rotor spinning provides a means for it to retain a quantity of oil even though it is on its side.
And,
An amount of that oil will be forced out of the rotor because of centrifugal force as the rotor orbits at crank shaft RPM.
And, some of the ejected oil will be replaced on the run by the oil jets. The quantity of oil will be changing depending on aircraft attitude, and engine oil pressure (RPM). Since the volume and weight will vary during operation, any reasonable guess will be correct. It almost doesn't matter because the oil is such a small percentage of the total rotor weight. If forced to decide I would "Guess" 1/2 to 2/3 of the total volume.
The Apex seal, corner piece (if any) and spring are not included in balance weight.
Lynn E. Hanover
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