thanks joeairport, the key is that prop should always stay where you stop it regardless of angle - bought a new one last week - it is hard to tell in hobbyshop which one is ok - I sanded off nearly 1/4 of hub to balance it - had to throw it away too dangerous. I am wondering if I should be adding weight rather than sanding it off? I have always sanded on back side of tips with flat sanding block then I apply thin ca using my finger w. a glove spread it around to re seal the wood - dries in 3 minutes ready to go. I always have to take off a little more wood to allow for weight of ca.