I'm sure this has been done before....but I grew tired of hole saws wobbling and not doing a good job of cutting, especially at angles.
I took a small, free piece of scrap 2-1/2" round steel and cut one end to 3/4" dia and on the other end I made a small register of .578" which centers the hole saw. The 4 small holes are 1/4" on a 1" BC.
This mandrel - unlike the ones they sell for hole saws - does a great job of damping the usual chattering and keeps the hole saw running true. The hole saws still have about .030" of built-in runout, but that's tolerable in most cases.
I took a small, free piece of scrap 2-1/2" round steel and cut one end to 3/4" dia and on the other end I made a small register of .578" which centers the hole saw. The 4 small holes are 1/4" on a 1" BC.
This mandrel - unlike the ones they sell for hole saws - does a great job of damping the usual chattering and keeps the hole saw running true. The hole saws still have about .030" of built-in runout, but that's tolerable in most cases.