Unless they have been damaged, or just plain worn out, chainsaw cutters can be sharpened. This takes some skills and knowledge that most do-it-yourself types don’t have and so it is well worth the expense of having a professional sharpen the cutters. An improperly sharpened chain can cause severe kickback, vibration, and serious injury. Or, it may simply not cut, causing the operator to put undue pressure on the saw and increasing the likelihood that the saw will slip and injure the operator. Proper sharpening and care of the chain is crucial to operator safety, don’t scrimp.

As a new chain is used it will stretch. As it does it becomes slack on the guide bar and needs to be adjusted. If left that way, the chain will eventually jump off of the guide bar. At the same time, the slack chain will be causing damage to the guide bar and the drive sprocket that makes it rotate, so it is important for your safety, and life of your saw, to adjust the chain periodically. Check the manual for your saw on how to do this, different makes and models may have slightly different mechanisms.

Many manufacturers put an adjusting screw on the saw right on the end where the bar sticks out of the unit. To adjust the tension on the chain all you do is slightly loosen the bolts that hold the bar on and then turn the screw in until the slack is gone from the chain. With the chainsaw sitting on a workbench or table, adjust the screw until the bottom of the chain links on the underside of the guide bar just touch the bar. You should not be able to see the drive teeth of the chain; they should be inside the bar, with the bottom of the chain link just touching the bar. That’s enough tension. Putting too much tension on the chain can damage the guide bar, so you want just enough, but not too much. Then tighten the bolts that hold the guide bar on.

If you are putting a new chain on, check that the shoulders of the guide rail are square and not rounded off or worn unevenly. If they are worn, the new chain will wear unevenly, thus shortening its lifespan considerably. Also check to make sure the guide bar is straight and not bent to one side.