Hi, new to stone fabrication but I got a budget to build a CNC machine to mill granite and as a non-required goal to also engrave simple reliefs on leftover pieces. The build of the frame and motion system are nearing completion but I'm finding it hard to find any accredited information on how to choose abrasive finger bits. I would trial and error my way through a variety of bits if they weren't so expensive for someone starting off. I'm using a 110V 2.2kw water cooled spindle with RPM's up to 24,000 (this RPM is the limit of my spindle, I'm not looking specifically for a bit that requires this RPM). Its collets can hold a shank up to 13mm or 1/2" but I'm prepared to order an adapter from a machine shop if absolutely necessary. Any advice is greatly appreciated!