Original message is below.
There were no replies to this thread but I was so pleased
to have some success with this technique that I'm making
this short followup.
The technique of using an electric hand drill in a drill guide
such as those sold by Sears plus one of the RotoZip bits can
successfully cut through a 3/4 piece of fiberboard. High speed must
be maintained and eye protection must be worn. I snapped a
couple of the RotoZip bits before using steady high speed
and a very gradual turn to make my cutout.
There would be more control with an actual spin saw or RotoZip
tool. The the gear supplied in one of the kits to make circle
cuts and so-on would be the preferred method of work. But for
me, the practice with tools I have gave me the encouragement
to get a spin saw very soon.
Main difference between the drill setup and a spin saw is the
mandrel rotation: the spin saw has a much higher RPM than
a hand drill.
Eye protection is critical.
The last question that remains to be answered for this setup
is whether or not the sole plate of the drill guide would
accept a calibrated Jasper Circle Jig for increased
I've posted after my initial try at this. If there is interest
send me a mail and I will answer any questions.