Jon,

Thanks for the info. I've obviously have a lot to learn hehehe. Is there some type of chart to read and calculate these ?

BTW right now I'm using CVD diamond tipped tools on 2mm (approx 1/8th inch) shanks - mostly ball shaped with no real flutes (more like a burr). I quit using anything but diamond because as you indicated they burn up too quickly. When and -if- I do get a mill I'll probably continue to use diamond though not CVD exclusively. Every bit I've bought in diamond I still have and use - even on green porcelain and sometimes on an occasional screwup I use them on bisque porcelain which is about like a grindstone to any tool. As a note for some reason in the U.S. diamond tools cost about 2x the price here in Japan.

--TC