Sharpen every time you refuel.

I sharpen mine every time I fill the tank. That’s the easiest rule: one sharpening per tank of gas. Dull chains are dangerous—they make you push harder, overheat the bar, and kick back more often.

Beyond sawdust turning from coarse chips to fine powder, look for these signs: the chain pulls to one side instead of cutting straight, you have to bear down to make it bite, or the cut slows way down. If you see smoke or smell burnt wood, you’ve waited too long. Also, if the chain won’t self-feed into the cut—you have to force it—it’s dull.

A quick touch-up with a file takes two minutes. Future you deserves a chain that cuts instead of fights.