One thing to note, and I learned the hard way. If you're using it for segmenting, then drilling a pen blank, watch when drilling. I was using a brad point, and once the lips cut through, the small aluminum disk won't come up the flutes of the bit, and you can end up blowing the glue joint apart if you keep pushing... stop and clean the metal off each time you cut through one.
Ii know, this was as clear mud, I'm sure)