I use the 3/4 and 1 inch diameter "High Speed Rotary Files" for every popper I make. If the face is larger I work the 1" ball around.
The only place I have been able to find these tools is Discount-Tools dot com. If you pay for the premium shipping you will have them in 2 days. The 1" File is about $22
Tip, do not use a metal brush to clean the files. I use a tooth brush or my air hose. Keep'em sharp
