Thread: PSA Sanding Disk Kit Supplies are in! If you ordered one then pls. read this post.

So only 3 grits are done. I spent half a day trying to improve the speed of punching...

So, now that you are almost done, how bout this:

One of those hole saw bits. Grind a taper from the outer wall to the inside diameter at the cutting edge. This eliminates all teeth and leaves a knife-like cutting edge. Polish it. Put it in a drill press and cut away. Don't know how long it would last on the rougher grits.