A critical part of chainsaw safety and maintenance is a regular program to sharpen your chain blade so it can cut effectively. The level of sharpening described here is suitable for touching up the blades on the chain to keep the chainsaw in good working order. You might do it once or twice in a day while using the chainsaw. After ten or fifteen such sharpenings, take your chainsaw to a professional who will grind the teeth accurately to the right angle.
Avoid cutting dirty wood or roots. Dirt and grit dull the teeth of a chainsaw very fast.
You’ll need a chainsaw file or rat-tail file of the correct width and angle for the size of tooth on the chainsaw you are using. You may also wish to use a file guide. Some people prefer to sharpen freehand.
Before starting, clean the chain. Put a heavy glove on the hand that’s going to be holding the chain and bar. Mark the first tooth so that when you have worked all the way round, you know when you are back to the beginning again.
Place the chainsaw in front of you on a sturdy bench or table, preferably at about waist height. You might want to clamp it. The technique is to insert the tip of the file into the notch or crooked tooth on the first link, at the same angle it was cut. The file should fit into the curve of the cutting face and come about flush with the top of the tooth. Push the file away from you, across the cutting face, firmly and smoothly. This takes the worn edge off the tooth to leave the edge crisp and sharp again. Depending on the degree of wear on the tooth and the sharpness of the file, you may need to repeat this firm stroking action three to five times per tooth. Sharpen each tooth the same amount. Otherwise, you will end up with a chain that cuts unevenly.
After sharpening the first tooth, advance the chain round to the next tooth that faces the same way. When you have sharpened all the teeth facing across, turn the chainsaw round. Repeat the sharpening action on all the opposite-angled teeth. Check for uneven or damaged links, oil the chain thoroughly and you’re good to go again.
For more detailed advice on sharpening your chainsaw, have a browse through Chainsaw Sharpener Tips.