I used an aerolsol spray on lube that I have found to work good on aluminum. Its marketed here by Canadian Tire stores, and from reading the can, it sounds a lot like a generic WD40. One thing I didn't do was "stone" the edges of my cutter, as the only stones I have are big flat ones, and I was afraid of stoning away the radius. My mill is not very large---Its a typical Chinese import. The gears turned out very nice, but I'm not sure if I would make them again using a single point tool. I know that you can buy a round cutter that is disc shaped, with about 4 notches in the diameter, which would probably be a lot easier on the machine. This was more of an exercise to "See if I can do it." I hear a lot of people on these forums who have trouble with the gear drives on these Chinese mills, and it seemed to me that the pounding that mine got making these gears is not something I want to repeat.----Brian