Model Forum / Radio Controlled / Helicopters / March 2007

I placed a couple of NEW main shafts on a piece of flat black ceramic with a
bright light on the opposite side to my eye.

The visible light between the shaft and the ceramic moves from the middle of
the shaft to the ends as the shaft is rotated.

The gap is very small but the shafts are clearly not 100% completely
straight even though they are new.

What is the acceptable level of tolerance on a main shaft?

Thanks

Adrian.