Even the best chainsaw cuts only as well as the sharpness of its chain. Although a few chainsaws come with built-in sharpeners, with most you must do the sharpening the old-fashioned way with a separate sharpener. You can have the chain professionally sharpened for $5 to $10, but it's time-consuming to take it to and from the shop every time it gets dull. If your chainsaw sees heavy use, it's more cost-effective to invest in a good sharpener you can use at home.
We couldn't find any professional tests of chainsaw sharpeners, but the Buffalo Tools ECSS Electric Chainsaw Sharpener (Est. $40) gets solid reviews from more than 400 owners posting at Amazon.com and HomeDepot.com. This electric sharpener mounts to a bench, wall or vise; if you don't want to grant it a permanent station on your workbench, reviewers suggest bolting it to a piece of wood that you can clamp in place when you need it.
To use the sharpener, you plug it into a standard 120-volt wall outlet. Then you remove the chain from your saw and feed it link by link through the machine, and the 85-watt motor spins the grinding wheel at 4,200 rpm to sharpen each tooth as it passes by. You can adjust the angle of the sharpener to work with most popular chain designs. Most users say they can sharpen an entire chain in 5 to 10 minutes, but a few say it takes as long as 40 minutes for a 20-inch chain. In fact, some users think sharpening a chain with the ECSS actually takes longer than sharpening each tooth by hand with a file — but on the plus side, it's easier to get a consistent grind from tooth to tooth, leaving your chain as good as new, if not better.
Owners' biggest complaint about the ECSS is that the instructions are confusing. Many reviewers say they discarded the manual completely and simply worked out how to set up and use the machine by themselves. We also saw a few complaints that the device's construction is flimsy. Some reviewers say there's too much wiggle room in the chain setup, making it difficult to position the chain at exactly the right angle. Others complain that the sharpener broke down after anywhere from a month to a year and a half of regular use. However, most owners still find the ECSS a great value at $40, saying it saves them considerable time and money compared to professional sharpening.
If you're confident in your ability to "freehand" sharpen and you already own a rotary power tool, the Anytime Tools Diamond Chainsaw Sharpener Burr (Est. $10) set is a cheaper and faster option. This kit comes with four diamond-coated sharpening burrs, each with a shank diameter of 0.125 inches and a burr diameter of .188 inches, ranging from 120 to 150 grit. By simply fitting one of these burrs onto a rotary tool, such as a Dremel tool or an air die grinder, you can sharpen your chain without even having to take it off the saw. Using this method, owners say, you can sharpen an 18-inch chain in two to five minutes. The burrs can also be affixed to a slower-spinning rotary drill, but it takes a bit longer this way: about 10 minutes for a 16-inch chain.
Most users say these sharpener burrs are very durable, as the diamond coating doesn't shatter like sharpening stones can, and they won't overheat your chain even on low speed. Their biggest drawback is that you have to have a rotary tool to go with them. Also, because you have to rely on your own hand and eye to adjust the sharpening angle, you don't get the same guaranteed, uniform results as with the Buffalo Tools ECSS. However, if you have the right tool and a steady hand, owners say these Anytime Tools sharpeners are quick, easy, and a great value.