The Cutter Caper

T he essence of skillful cutter grinding amounts to being able to produce cutters that are sharp yet sturdy, cut with little pressure, and evacuate chips well.When machining problems arise, often the problem can be traced to a faulty cutter. If you know how to choose, grind, alter and inspect cutters, you’ll be able to do virtually any job that comes along.

Cutter grinding is an area of our trade that I believe separates the craftsman from the hack. Paradoxically, cutter geometry is not the complicated issue many cutter and insert manufacturers would have you believe. There is likely a  wide range of cutter geometries and grades that will work for any given job.

I remember asking an accomplished machinist some years ago what shape tip he liked to use for fly cutting.His answer surprised me and yet thinking back on the exchange, I realize how accurate his answer was. He said “anything.” And he was right as long as you add a

F IGURE 7–1 Deckel® cutter grinders are versatile machines that can be used to grind and sharpen a variety of cutters.

qualification. The leading edge of the cutter must be the first and only thing to contact the work. As long as that is true, just about any shape will cut.