Sounds easy enough!
Go to Walmart and buy a 5/32 or 3/16 or what ever your chainsaw is. Most use the 5/32 rat tail file or round file. Make sure you get the guide to snap your file in. No one can sharpen a chain without one properly. If you do not use the angle on the guide, your chainsaw will start cutting on a angle making cutting large logs useless. If you touch dirt it will dull. and if you hit a rock or concrete sometimes metal it is almost better to buy a new chain if it cuts on a big angle after you sharpen it. People that sharpen blades usually cut too much off and after 3 sharpenings you have to buy a new chain. They charge almost ½ the price of a new chain to sharpen and you can sharpen it in 10 minutes. 1/3 of the time other people sharpen my chain they ruin it. Add up the cons and do it yourself.!
Hint: $2.50 file will only last 3 sharpening sessions, so don't stretch your luck for more times.
Pinkpanther
April 2008