Airy R. Bean wrote:
Assuming that one could obtain a slab of marble for the
base of a home grown bug key, is it an easy thing to
polish and to drill?

Does one use ordinary masonry drills?

Any undertakers out there?

A quick Google search on "drill marble slab" came up with hits to
support my first idea for drilling the marble: use a copper tube
the diameter of the hole you want, in a drill press at _low_ speed,
with lots of (fairly coarse) abrasive powder, lots of water, and low
pressure on the drill bit. It's the same rig I use for drilling glass.

You will want a stream of running water so that the bit is kept cool
and lubricated, and the abrasive doesn't turn into a hard paste.
It will be messy; if you can put the slab in a cookie tin or
aluminum-foil pan, and run the excess out through a tube, that will
help. You also could build a modeling-clay dam around the hole.

It's almost impossible to over-lubricate, but it's really easy to
under-lubricate.

See http://www.shopsmartxpress.com/Ameri...lt.htm?M9a.htm
for some useful tips.

Polishing is easy: coarse-to-fine sandpaper, then buff with increasingly
fine powdered abrasive, up through white rouge or so. You have to get
all the old abrasive out of the polishing tool before you put the new,
finer abrasive in -- but you knew that.

Marble is rather soft, though quite abrasive, and so it's easy to
take off more than is necessary.

--
Mike Andrews

Tired old sysadmin