I want to cut some zero-clearance inserts for my table saw by using the existing insert plate as a template, screwing some 1/4 inch MDF blanks to it, and trimming it with a flush cutting bit in my router table. However, if I push the shank of the router bit most/all the way into the collet, the roller bearing does not protrude above top of the table. Should I just re-position the shank with more "air" between it and the bottom of the collet? Could I drop a short length of 1/4" dowel down the hole to fill the space or is that either unnecessary or unsafe? Thanks.
Lee