CeeGee, one thing that I found that was rattling on my ucando was the control surfaces. When I checked them there was just a little bit of slop, not much, just about a 1/16 up and down and I have to replace the rudder servo today with a newer one. When I got them tighten up the humming sound diminished significantly. About the spinner, I had the same thing happen to mine, I had a black one and I thought that it was a wheel that fell off! Now I use a prop nut that looks like a small spinner (can't remember what it is called) that is made from aluminum.

gjeffers, A good trick to help the epoxy on the block is to get a 12 in 4-40 rod and drill two or three holes thru the block next to the bamboo stick that great planes used and epoxy them in there. Hardly any weight and it makes the gear so much stronger. I will post a pick of the ucando with them for you, just have to find the camera.