Why goof around with using steel washers that are not all the same thickness. Here is a quick an simple way of spacing out your motor. The base stand off is precision machined from 6061-T6 aluminum. It measures 1" diameter at the base to give a good load bearing on the wood, and necks down to 5/8" in diameter at the motor and has a 1/4" thru hole. If more length is required, simply add the spacers included to get the desired length up to 7/16" of added length. Kit comes complete with (4ea.of the following) Stand off bases, plus 4 ea.)1/4", 1/8" & 1/16" boss extensions included.