For ideal results, place file against beveled cutting surface of the teeth 20° to 45° with saw and file from the inside to the outside of cutter. Sharpen all left-hand cutters on one side of the chain and move to the other side and file all the right-hand cutters. The height between cutting teeth and depth gauge is between .020" to .030" — check the depth gauge height every 2 or 3 sharpening's. Tighten the tension on chain to firmly support cutters when filing. American pattern round chainsaw file. Tighten tension on chain to firmly support cutters when filing. Place file against beveled cutting surface of teeth 20° to 45° with saw. File from inside to outside of cutter. Check depth gauge height every 2 or 3 sharpening. Height between cutting teeth and depth gauge is between .020" to .030". Place file against beveled cutting surface of teeth 20° to 45° with saw.