Follow the manufacturer's specifications for safe usage Place file against beveled cutting surface of teeth 20° to 45° with saw Sharpen all left-hand cutters on one side of chain and move to the other side and file all the right-hand cutters File from inside to outside of cutter Check depth gauge height every 2 or 3 sharpening's Round American pattern file with knurl cut Tighten tension on chain to firmly support cutters when filing Height between cutting teeth and depth gauge is between .020" to .030"