Quote Originally Posted by tmate3 View Post
(edit . . . ) With a 7" drive wheel top speed is just over 6,500 sfpm (surface feet per minute). I haven't tried grinding anything yet above maybe 3,000 sfpm, but with a 36 grit belt even that was scary fast at removing steel.
I have always used the yardstick of 4,000-4500 max FPM and 1HP per inch of belt width. It is a beautiful and versatile grinder design, but as you indicate, 74 MPH seems a bit much.