Hey Nicad,
I have seen discussion here on CNCzone, on allowing a few tenths more endplay on the Sherline spindle when upping it to 10,000rpm because of bearing frictional heating of the spindle. Clearly, the housing is in contact with the surrounding air so it enjoys a little convenction cooling and some radiative cooling, too! The poor lil spindle gets neither. For 30,000rpm I wonder if having one bearing an easier fit in the housing, and backed with wave washer/s to allow it to move axially while never being loose, could be worth playing at? Wave washers - wavy washers - wave springs - can be selected for a range of spring constants and travels. I use English EMO brand but there are beautiful examples from Smalley and others . Regards, Terrence |