There are many things to take into consideration when choosing a chainsaw sharpener including how much you want to spend, whether you will be using a chainsaw regularly or occasionally and how much physical effort you are willing to put into sharpening a chain.
There are basically two main types of sharpener to choose from - a manual or electric device. Manual devices include round or flat sharpening files and small grinding stone sharpeners which look similar to a standard drill bit and can be attached to an electric drill. These cost around £5 so they are a very cheap way to get a chain sharpened. A highly respected brand name when it comes to hand files and manual sharpening kits is Stihl.
Manual files operate in a similar way to a hack saw in that you saw back and forth by hand to sharpen each of the cutting teeth on the chain. These are the cheapest sharpening option but take considerably longer to get a chain sharpened.
If you have a cutting tool like a hand-held Dremel, you can make use of a special blade that attaches to the tool to will sharpen most chainsaw chains.
Manual hand files are very cheap and have been used for decades by amateurs and professionals alike for sharpening a dulled chainsaw chain. If you own a small chainsaw which you only use occasionally to cut trees and shrubbery in your garden, you will probably be fine taking the cheap option and buying a manual file.
Electric manual files can also be operated away from home and can bed used with a handy rechargeable battery, or they can be connected to your 12V car battery or cigarette lighter socket.
A key benefit of a manual file is that it can be taken out to a job in case a chain needs sharpening while you are away from home. It should be pointed out, however, that it can take a while to master the art of using a handheld round file, so if you are not very competent when it comes to DIY skills, a fixed bench top sharpener may be a better option for you as it will sharpen all the blades on a chain very accurately, with minimal effort.
When considering which sharpener to buy it's important to think about how you plan to use the sharpener, where you plan to use it and the quality of the sharpening you require. Professional style bench or wall mounted powered units will always give the best quality sharpening results. This type of sharpener is more expensive but basic models are very affordable at around £20 to £40. A top of the range heavy duty bench sharpener will cost considerably more, however it will be capable of sharpening many chains very quickly, making it ideal for professionals.
When opting for an electric bench-mounted sharpener, you should choose a unit with interchangeable grinding wheels and at least a 1/4 horsepower motor which has a good exhaust fan. Aluminium fins on the fan are better than plastic. Reputable brand names for bench top sharpeners include Terratek, Voche, BMC, Silverline, Maxtra, Powerplus, Sealey, Neilsen, Oregon and Clarke.
Most good quality chainsaw sharpeners have a simple head angle adjustment system that allows them to sharpen a wide variety of chains. The best units allow you to make accurate and gradual changes simply and quickly so you can sharpen nearly all types of chain designs. If you own a popular brand of chainsaw most sharpeners will be compatible, but it's always worth checking before buying.
When choosing a sharpener its worth looking for one that has the ability to sharpen a range of chain types - including semi chisel, full chisel, ripping, low profile and skip - at a range of pitches. This means you will be able to use it if you ever decide to switch to a different chain from the on type currently on your chainsaw. To cover a range of pitches you must be able to adjust the cutter angle from zero to around 35 degrees. This will be suitable for most chains.