We know props have to be well-balanced, as do spinners - but - there seems to be some shortage of "how to" for balancing the spinner parts. I have the Dubro balancer that works very well on even large props.... but I haven't been able to figure out how to do an aluminum spinner properly and accurately.

Any and all insights appreciated!!!!

hope this helps.[:-]

http://www.rcuniverse.com/forum/m_5003303/tm.htm

After I modified my GP YAK spinner to accomodate a 22 inch prop I put it on my GP prop balancer. It was way off. I do not know if it was the best balance job but I am certain I improved it considerably.

Yep. Helped a BUNCH, interesting that you asked two days ago!!!!!!!! I guess we "all" need the same info at some time....
Worked really well....after modifying the Dubro balancer to let the spinner fit.

Doesn't solve longer spinners, like 4" Ultimates... but at least I have the idea better than I did before.
Thanks!

Hi Bob, you while you may be able to balance the spinner statically, it may not be dynamically balanced. So, you gotta be careful

Tell me more, Mike. I'm listening....

Hi Bob, let me see if I can get a diagram somewhere and post it here for ya

Bob, here's a nice writeup on the subject of spinner dynamic balancing from the other Bob http://www.tru-turn.com/faq-11.htm

THAT is one of those "things that make you go "Hmmmm", for sure. Have to process that for a bit; when I did the stock SD spinner for the Extra, it was more out than I thought. Bob's article makes sense when in the context of very tight machining tolerance and materials consistency.

But - on the "other" than his spinner - I'm tending to think a little "fixing" to get it closer is better than NOT fixing.

Thoughts, anyone?

My only counter arguement to the Tru -Turn faq is that you are not balancing a cylinder, you are balancing a cone. It seems an imbalance at the "tip" of the cone will not nearly be as dramatic then at the "base". When I balanced mine I had modified the base section to fit the prop - so when I balanced it I took material from the base.

I agree, a dynamic balance would be better and would likely require some instrumentation? Probably vibration detection and then there is the problem of where to remove or add weight. At work I have seen how complex this can be with large rotating equipment.

Maybe you could just put the spinner on drill or something and spin it up and just kinda judge from inspectiion? Also maybe wear some safety glasses [8D].

Here's my logic - perhaps flawed and full of holes - but -
I think making ANYTHING "better" by static balancing is an improvement over letting something spin away that induces a "flywheel" effect on the prop hub. Reducing ANY of that surely MUST be better than IGNORING it.....

But like I said - my logic may be flawed.....

Aerobob,

I agree with you, but only because we are dealing with a cone. If this were a cylinder or a shaft then you would have 2 effects to worry about: The imbalance between front and rear which would induce a wobble around the center point, and the imbalance of too much weight on one side of the shaft, which would cause a wobble around the shaft.