The "diamond" in the name refers to the shape of the tool shaft, not the
inclusion of any actual diamond material. A diamond parting tool has sides
that are relieved, resulting in a roughly diamond-shaped cross-section. The
advantages of such a tool are that only the side "points" of the diamond
contact the sides of the cut, making it much safer and easier to part
deeply. They are more expensive because of the extra machining operations
that go into them.

When you sharpen it (with exactly the same equipment that you sharpen all of
your tools), make sure that the point formed by the bevels on the face meet
at the side points, the thickest part, of the cross section.

Michael Latcha, at home in Redford, MI


"warpedwoodturner" wrote in message
ups.com...
I got a moderately prices diamond parting tool from Penn State
Industries. Up until now I have never tried to sharpen it but rather
rub both edges on sandpaper lying flat on a workbench. When I hear
diamond I think of something harder than a grinding wheel. Does
anyone know how they make diamond parting tools (micro diamonds in the
steel I assume) and if how they are made makes any difference on
sharpening them? Thanks and Happy New Year