Right! If they are seriously out of balance, then yep, that's a great way to see (check) that. Then it should be put on a proper balancer and done correctly. Out of balance props can cause a lot of problems all the way back to receivers that are sensitive to serious vibration.

By the way, I use a fine grain sand paper and remove stock on the rear of the prop. It usually is very little and does not cause any problems with the performance of the prop. At least none that I can notice. My OS 1.20 AX's will still pull the plane vertical and just about out of sight.

CGr.