Router (or handtools) to carve limestone?

["Simon Brown" <moonsong@zzzzzzzzzzzzzzz>]

Dan,

Granite City Tool has a good range including diamond bits as well as books &
videos http://www.granitecitytool.com/stone/tool/stone-etching.cfm I've
never bought from this company as I live in Australia and there are other
suppliers here. Depends how much money you have to spend on tools... I agree
with John's comment about hand and pneumatic chisels being the best for
lettering, but some of the diamond tools are relatively inexpensive, and may
suit your purpose. I don't think there will be much to read about how to do
it, sometimes it's best to have a stab at it with what you reckon will work.
John Pitt has an excellent site with extensive links
http://www.incisiveart.com I agree with John's recommendation about the
carbide bits burning up, the limestone can also 'burn' or scorch and
crumble- so take it steady.

If you tell the tool manufacturer what stone you are shaping, they can
select the right matrix to match. The matrix is the metal that holds the
diamonds together, generally a soft matrix for hard stones and hard matrix
for soft stones. This allows the matrix to alternatively wear and expose the
abrasive diamonds, or to resist wear to protect the diamonds. If the tip
gets hot, the diamonds can fracture and fall out, or the matrix can 'glaze'
or harden and cover the diamonds. There are different grades of manufactured
diamonds too, generally the cheaper the softer.

Let the list know how you go!

Simon