Chainsaw Repair

Just sharing a store bought version I seen as I dont use such things. 
Dont look like it would be any good for square filing unless you raised it up someway.

Logosol Filing Guide  http://www.baileysonline.com/Chainsaw-Chain/Files-Filing-Accessories/Chain-Filing-Guides/Misc-Filing-Guides/Logosol-Filing-Guide.axd




Filing guide from Logosol. The Logosol filing guide is a chain clamping vice, designed to hold your saw chain firmly for perfect filing results. Most filing guides require you to use your chain saw bar to secure your saw chain, which is usually sloppy at best. The Logosol guide has two clamps to tightly secure your chain in place, so you can file with exact angles. The guide also has built in angle guide lines at 30 degrees (for standard saw chain) and 10 degrees for ripping saw chain. Made of anodized aluminum and galvanized steel. Has two holes for mounting to a work bench. Fits 16" and longer saw chains. Approximately 15-1/2" long.