Had a very good day yesterday with the PAW 19. I still have no idea what caused the sever vibration two weeks ago but on the Mater Airscrew 9.5x6 it was the best flight I have had and it was up to competition level of performance.

I have not disassembled the engine to see if there was anything inside that was suspect, the puzzling thing is all I did was change the prop and the problem vanished!!! There was no binding but does seem like it was something physical, any throughts?