If you are using a chainsaw you need to understand the principles of chain sharpening. Unlike pretty much all other power tools chainsaws are the most labour intensive when it comes to maintenance. Chain sharpening needs ongoing research and experience in order to improve skill level. Please take the time to read the chain sharpening info by clicking here. If you are serious about correct maintenance of your bar and chain work your way through the Oregon manual [click here] and after that check out the Stihl equivalent [click here].