balancing a 3-or-more bladed prop

Does anyone have any suggestions about how one can go about balancing a propellor with 3 or more blades?

Charles L

Reply to
Charles L
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Does anyone have any suggestions about how one can go about balancing a

propellor with 3 or more blades? Composite or wood? If it's composite, and VERY OOB, take it back or throw it away. These props should NOT be sanded to balance!!! You might be able to correct a SLIGHT OOB condition by spraying the two light blades with poly-u.

Wooden props can be balanced easily using the poly-u method. I don't recommend sanding ANY prop to balance it.

Reply to
Dr1

I think the question is, "If one blade is heavy on a 3-blade, how much weight do I add to add to other two to make it balance.?" I have an autogyro with a 3-blade rotor that I'm trying to balance, and I'm wondering the same thing.

Morris

Reply to
Morris Lee

Should be on the order of the sine of the weight needed, for each light blade, I think. That should be around .707 times the difference that you'd hang on each blade. Just my guess, mind you... Dan

Reply to
Dan_Thomas_nospam

Correcting my earlier post: all the blades should be the same, so you'd bring each light blade up to the weight of the heavy blade. That's assuming, of course, that the blade's weights are evenly distributed along the span. You might have three blades the same weight, but one my have more mass at the root, one with more mass in the middle, and one with more mass at the end. All would weigh the same but it sure would shake when turning. You'd want to balance them at midspan as well as getting them to the same weight.

Dan

Reply to
Dan_Thomas_nospam

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