My recent Prepography article “8 Tips For Using A Chainsaw” gave the basics on using a chainsaw. Having a sharp chain is very important for safety as well as productivity. Chains will dull very quickly, especially if cutting an extremely hard wood such as hedge. Knowing how to sharpen a chainsaw is an important skill to have. Not only will it increase the effectiveness of your efforts, it will save you money to boot because you’ll use fewer saw lubricating oils and won’t have to pay someone else to do it for you.
1) Determine Your Chainsaw’s Gauge – You will need a rotary grindstone or chainsaw file that matches the size of the chain’s teeth. You can also buy a chainsaw sharpening kit that has everything you need in it, like the one to the right. Typical sizes are 3/16, 5/32 and 7/32 of an inch in diameter.
2) Thoroughly Clean Your Chain – Use a brush and solvent to clean dirt, dust and debris off the chain.
3) Inspect Your Chain For Damage – Look for chipped, broken, or bent teeth. These will make a chain dangerous to use. If a tooth is worn short, it is at risk of breaking during operation, which is extremely dangerous to the operator. Replace any chain that is worn or damaged.
4) Place Your Saw On A Solid Surface – For safe and accurate filing your saw must be stable and the blade firmly supported. Use a vise to clamp the bar while allowing the chain to rotate freely is the best option.
5) Locate Your Start Point – The lead cutter on a chain is the shortest cutting tooth on the chain. If you can’t locate it, just take a permanent marker and mark a tooth as the starting point.
6) Set Your file Into The Notch On The Front Of The Cutter – The cutter is the angled “tooth” on the front of the flat surface of the chain link. Your file should exactly fit the curve of the face of the cutting tip. The top 20% of the file diameter should be above the top of the tooth. The file should be at the same angle as the cutter. Also check your saw’s specs to find out what that correct angle is. Usually it is a 25 or 30 degree angle
7) Push The File Across The Face Of The Cutter – Using a twisting motion push the file across the cutter. The twisting motion help get the metal filings out-of-the-way. Do this on every other tooth until you have made one full rotation of the chain.
8) Reverse Sides And Repeat – Once you have sharpened all the teeth from one side, switch to the other side of your saw and repeat step
9) Check The Clearance – Check the clearance of your depth gauges which are also known as the rakers. These curved hook shaped pieces link the cutters. They govern the amount of wood that the cutter removes on each pass. They should be about one tenth of an inch lower than the cutter. A special tool called a Depth Gauge Tool is available online or from chainsaw dealers or hardware stores. You can eyeball it if you don’t have one but the tolerances are pretty small so use the depth gauge if possible.
10) Oil The Chain & Check Tension – Saturate the chain with oil. Then, check the tension to ensure it is not too loose, or tight. Adjust as needed, and you should be ready to cut again.