Sharpening Basics

A few basic rules to sharpen chainsaw chain properly.
Always reference your saw's owners manual for proper chainsaw safety and use. In most cases your manual should have important information about your saw chain and file size.
Make sure you have the right size file to match the saw chain. The diameter of the file must match the radius of the cutter tooth's gullet. I always keep several size files handy, but I have many different size chainsaws. Hand held files are fairly cheap to buy.You should always keep a few extra around because a dull file is just as aggravating as a dull chainsaw. After several filings you will notice the file not taking nearly as much metal filings off the tooth you are filing. Pitch it in the trash and enjoy a new one!
Mark one tooth with black magic marker so it is easier to see where you start and stop filing. File each tooth from the inside of the bevel angle outwards. You should file every other tooth,then flip the saw around and file the remaining teeth the same way. Unless you have hit a rock, don't take anymore than 3 strokes per tooth. Two is usually sufficient.Excessive filing will severely reduce the life of your chain.
I always use a file holder because it will usually have a witness angle that you can line up parallel with the bar. This angle is usually 25 to 35 degrees across the face of the cutter. It is important to reference this angle to match the manufactures recommendations. The file is also usually held at an upward angle of about 5 to 10 degrees. But again, you should check with the saw chain manufacturer's specs first. I have seen a few chains that are filed a 0 degrees (horizontal)
The real key to successful sharpening is being consistent. File each cutter tooth exactly the same. An uneven chain will start to veer off course and will start to bind up in the saw kerf.
Check you owners manual on proper operation of your saw before ever using a chainsaw.
If you suspect you have filed the chain incorrectly then you should take the saw to a reputable dealer.They should have a professional that can use a bench type chain grinder to get your chain back in proper condition.
If your chain is sharp, you should be getting good production and the chainsaw will produce a good size wood chip.If your chainsaw is dull, it will take longer to get through a log and the saw will be making a lot more sawdust and not many saw chips.
One more step to sharpen chainsaw properly is correct depth gauge settings. Depth gauges are sometimes ground down with small rotary power tools such as a Dremel tool, but I like to use a flat file and a special gauge for accuracy. I talk more about depth gauges in the video on the sidebar of the site.