1. The cutting tooth on a chainsaw chain is covered with a very thin layer of chrome, providing it with a very sharp and durable edge.

As long as the edge is in the chrome layer youíll have a perfect edge on your chain.

Now itís time to file the chain. If youíre observant, youíll sense that the sawing speed is slower, the guide bar hotter and the feeding pressure increases.

3. If you file the moment you sense that the edge on the chain is no longer perfect, youíll only need a few light pulls on the file.

If you always file before the chain is dull, the wear on the guide bar and the chain will be minimal.

4. However, if you saw only 5-10 times after the edge has gone through the chrome layer, the chain will become so dull that it will be hard to saw. The saw speed will be low and the feeding pressure high. The guide bar and the chain will quickly overheat

You can still saw, but the equipment is worn out quickly.

5. When you file a dull chain, there is a risk that you wonít reach the chrome layer. The chain will be sharp, but since the edge isn't in the chrome layer, it will soon be dull again.

If you donít file in time, youíll have to file down a large part of the tooth to get it sharp. The working life of the chain will be short.

If a large part of the sawing is done with a dull chain, a higher feeding pressure is needed, causing rapid wear on the guide bar and increasing the risk for a chain breakage.