I've been practicing clay sculpture for a while, and finally feel up
to carving in marble. I took a class last week, and the previous
week carved a little relief portrait.
My greatest frustration is getting spectacular detail work. Hech,
even simple details. Stone, unlike clay, is brittle and doesn't take
well to sharp incisions or undercuts. But Bernini, my email address's
namesake, could get fine, sculpted hair; pearls; even lacework and
I am told that the solution is to cut, not chip-- to drill out all
undercuts before then going in with tiny chisels to clean it up.
Someone told me to get a bow drill; that's what they used to use.
But a suitable bow drill, with the handle up rather high from the
point of the work, very hard to find and only antique, and which has
to rotate back CCW to rotate CW and cut again, is very awkward. There
must surely be a modern counterpart, commercially available, new and
I don't really have any experience drilling stone. Marble is soft
enough that steel can cut, but it dulls within hours. I trust that I
want carbide? Or perhaps diamond? Marble will be softer than any of
the semi-precious gems you carve, but techniques should be very
similar, which is why I am taking these questions here. Most marble
carvers these days are rather abstract, with little time for detail.
Detail doesn't pay hourly wages either; but I'm doing it for myself.
I noticed that foredom offers a 5k max rpm, high-torque/low-speed
grinder. Is this what I will want, for stone? Will I desire carbide,
or diamond; and if carbide, drill bits, mills, or router bits? What
precisely is the difference between a router bit and an end mill?
Where do you prefer to buy your bits? I've found drillbitcity, with
resharpened bits. Precise dimensions do not matter here. Does anyone
supply rather longer bits, to slip it into a very deep undercut?
Is water as a lubricant perfectly fine with the flexible shaft?
Cleaning up any rough marks on details is another problem. You
simply can't get sandpaper or broken up whetstones into there. The
grinding stones I saw at harbor freight were massive, and at 20k rpm
would grind far more than polish, but maybe if I get smaller ones,
and if that high-torque/low-speed foredom can go down very low, that
would be just the thing. By polish, I mean an even, satin finish, to
look like flesh-- not a high gloss, 300-400 grit is fully sufficient.
What handpiece would you recommend? For mostly drilling marble, and
using tiny cones or balls to clean up the drilled & chiseled tiny
undercuts and detailed spots?
BTW, if you know--I can get marble with pinhead sized crystals,
though it's hard to get. Danby marble has more like 1mm-diameter
grains, Georgian with 1/4"+ Does grain size dictate the detail that I
can achieve, or do the cutter heads slice right through the crystals,
leaving as fine a line as I want, no matter how fine the marble
grains themselves? Perhaps your experience in the context of another
stone more popular in jewelry, something that has distinct grains
thanks for all the help!