Feathering spindles are pretty easy to remove/replace. In any crash they're one of the first things to go. After ANY crash, you really absolutely HAVE to check your mast and spindle. A slight bend in either one will give you very bad vibration.

To remove the Rap's spindle:

1) Remove blades.
2) Remove linkages to grips
3) Using a Hex Wrench plus either another Hex wrench of the same size or a pair of pliers to hold the opposite bolt, remove the bolt inside one of the grips. This bolt is the one you see if you look straight into the blade grip. There's a bolt at each end of the spindle.
4) These bolts hold the grips on. So with one bolt off you can now slip the blade grip off.
5) Now, you can just grab the other grip and pull. The spindle + blade should both pull out of the rotor head. The spindle is just held in there by 2 rubber dampers.

Now you can check it for bends. I'm betting you've got a bent one...

-edg-