Bernard Arnest wrote in news:7e14ebd7-7f04-4864-
:


There a
-cheap dremels with flex shaft, 5k-25k rpm
-better foredoms with flex shaft, 5k-35k
-slower speed, higher torque foredoms
-dental drills, like foredoms but with armature instead of flex shaft
-(mini) die grinders, air powered, 50k
-air dental drills, like mini die grinder-- maybe lower torque, but
better built?? Just guessing; would seem that professional dentistry
would have a higher standard than the $30 mini die grinders on sale.
-turbocarvers and their kind, air, 300k

any recommendations?


A few, based upon some familiarity with the use of some of the equipment
on wood, glass, and metal (copper, brass, steel - both hardened and
annealed - and quartz:

First of all, don't overlook Diamond burrs for working stone. The prices
have dropped considerably in the last few years and I've picked up
assortments of 50 burrs for as little as $5/set.

The HF "Micro Die Grinder" is a nice little thing - high-speed, quite
maneuverable, etc. - that uses quite a bit more airflow than they claim.
(You'll need a good-sized shop compressor if you plan to do very much
with one since the 2 CFM spec is an absolute joke - it's more like 5 CFM)

The flex-shaft dremel (and the imitations) will work IF you keep the
shaft well-oiled. Otherwise, you'll be replacing the shafts on a regular
basis.

Foredoms beat Dremels.

Keep in mind that Dentists don't need to "hog out" a lot of material at a
time since they're usually dealing with very small adjustments at a time.

For large-area work, you might want to consider 1/4"-shaft Diamond burrs
in a wood-working router.

Straight drilling is easy if you use carbide-tipped Masonry bits.