Section R. 408.10174 - Grinding machine spindle speedsRule 174.
(1) The spindle speed shall be permanently marked on a grinding machine and maintained in a legible manner.(2) The spindle speed shall not exceed the rated speed of the grinding wheel.(3) The wheel spindle speed on a single-speed grinding machine shall be checked with a tachometer when a change is made which could affect the spindle speed.(4) The wheel spindle speed on an air-driven grinder shall be checked with a tachometer as follows: (a) After maintenance or repair.(b) When in use, with such checks being performed as often as necessary to assure that wheel overspeed will not occur.(5) The wheel spindle speed of a vari-speed grinding machine shall be checked with a tachometer as follows:(a) When in use, with such checks being performed as often as necessary to assure that wheel overspeed shall not occur.(b) After any change that could affect the spindle speed.(c) When a new wheel is mounted.Mich. Admin. Code R. 408.10174