Sharpen, tension or replace — reading your chain.

Sharpening

Sawdust turning to fine powder is a dull chain. Five strokes with a 4 mm round file per tooth, same direction, same count on every tooth, restores most of the cutting speed in ten minutes.

Tensioning

A sagging chain derails mid-cut. Loosen the bar nuts, adjust the tension screw until the chain snugs to the bar but still pulls around by gloved hand, re-tighten. Wrench included in every kit.

Replacing

Jumps, derails, or cutters visibly chipped: swap the chain. Loosen the side cover, replace, re-tension. Spare 4/6/8-inch chains cost a few dollars — keep one per bar.