Section R. 408.10155 - Mounting of abrasive disc wheelsRule 155.
(1) An inserted nut wheel shall be mounted with a steel machine face plate of the same diameter as the wheel. The thickness of the machine face plate shall be as prescribed in table 19 of R 408.10199.(2) A screw hole in the machine face plate shall be located to match the threaded hole in the inserted nut and large enough so the screw will not bind. Each screw hole in the plate shall be countersunk to a uniform depth to accommodate the screw head. A screw shall engage the threads of the inserted nuts, but not touch the bottom of the hole.(3) A machine face plate shall be flat, concentric and mounted at a 90 degree angle to the machine spindle.(4) A plate mounted wheel having a mounting plate thinner than prescribed in table 19 shall have an additional machine face plate installed to provide the additional strength needed. The added machine face plate shall have the same diameter as the wheel (see figure 22 of R 408.10198 and table 20 of R 408.10199).Mich. Admin. Code R. 408.10155