rotorwrench
Well-known member
I used to have to test the who die dampers on the Bell 47 stabilizer bars. They had a test arm and a place to attach a weight. We would time them from full up to full down. They were a much newer design that used a screw type needle valve to adjust the rate and had a glass window to see the oil level and condition. They used MIL-H-5606 hydraulic oil on those. Houd Engineering made this stuff well up into the 1970s. The old Ford automotive types used the dog leg arm in order to fit in situ to make checkups easy for mechanics. There is a lot of info in the Service bulletins. The final service info published begins on page 536. The main thing is that the arm length and weight is the same whether is has a dog leg shape or not. It works either way but the dog leg works well on the car.
I used to do weight & balance on aircraft a lot after modifications. Weight X the arm give the turning moment for calculations. The arm on those tools is substantial and the weight is fairly hefty but not too big. They give the amount of seconds for timing the damper movement in that service instruction for nominal weather and for cold weather. I'd say that is could vary some but all should be about the same per the application such as front or rear. Most automobile shocks have a fair amount of resistance to movement otherwise they don't dampen the spring action very well.
I used to do weight & balance on aircraft a lot after modifications. Weight X the arm give the turning moment for calculations. The arm on those tools is substantial and the weight is fairly hefty but not too big. They give the amount of seconds for timing the damper movement in that service instruction for nominal weather and for cold weather. I'd say that is could vary some but all should be about the same per the application such as front or rear. Most automobile shocks have a fair amount of resistance to movement otherwise they don't dampen the spring action very well.
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