| 摘要 |
A process for making a file wherein the formation of the file teeth by striking a blank with a chisel-like bit also forms sharp serrations on the back sides of the teeth adjacent the cutting edge, with the improvement of preserving such serrations without substantial removal thereof during the cleaning and finishing steps of such file making process. Such process may include cleaning a formed and hardened file by directing a pressurized stream of frangible glass beads at the file to remove undesired materials associated with the hardening step. The file resulting from such process retains the serrations on the back sides of the teeth whereby wearing away of the original cutting edges of teeth during use serves to expose for cutting purposes some of the sharp serrations. |
