I seem to find more and more miss information on how to sharpen your chainsaw chain the farther I read through this section and feel I must say something before someone does something to hurt them selves or others....
First and foremost, an electric sharpener properly set up is far more efficient and accurate than hand filing. Hand filing does not hold consistent tooth lengths nor does it hold consistent angles. If your going to hand file properly you must carry a calipers and verify that each tooth is exactly the same length. Within thousanths of an inch. The throat and chisel angles are very critical to proper fiber severance and chip removal and only the most complicated of fixtures can duplicate a properly dressed sharpener wheel.
If you find that a freshly sharpened chain does not cut well first measure the length of the teeth from chisel point to back and ensure they are all the same length.
If they are the same length check that your not cutting too shallow or deep, as the angle of approach is everything.
If your chain dulls very quickly your cutting to shallow. Your making the cutting surface to long and thin and it is wearing or chipping off. For reference, I can cut approximately 4 hours continuously through hard oaks and hickory when we are clearing sections of land as long as I don't find any rocks or dirt or fence posts. That's approximately 8-10 cords of fire wood. Yet the chain isn't truly dull, but the saw is working harder than I would like. As long as the rakers are at the proper height and you never force a cut a chain will stay Sharp for a very long time if properly sharpened.
As far as rakers go.... Well there is so much misinformation is makes my stomach turn with visions of cut up legs and bodies. Raker depth is crucial to a fast clean cut. More is not better. Yes, manufactures make recommendations based on intended use, but the biggest factors are chain pitch, saw size, and type of wood being cut. A small saw with a safety chain will cut best with a .025" Raker depth. But a large saw, say 70cc or more with a 3/8 pitch chain cutting through soft wood may cut better at .035" Raker depth. Yet will cut better through hardwood with a .030" or even .025" Raker depth. The harder the wood the less of a bite you want to take. But with less of a bite you will still cut through the wood at the same speed because with a large bite your cutting teeth are skipping over the wood more than digging in. There is more load on the bearings and clutch, and you are wearing the tie straps because the teeth are being forced to "lean back" under the heavy load.
If your saw seems "grabby" then you took too much off the rakers and have a very very dangerous situation. Brute strength to hold the saw in a cut is ignorance at best. The saw could pull right out of your hand and land on you, not good.
This is a very rough over view but I feel the need to bring these poor and dangerous practices to attention.
The key points to a good cutting chain saw are this:
Keep teeth at equal length and proper angles.
Keep rakers at proper depth.
Keep proper chain tension and oil chain well.
Contrary to popular belief professionals do not file down the rakers for a faster cut. As a matter of fact some of the fastest saws use a very shallow Raker depth. The key to a fast cut is all the above + chain speed. A faster moving chain will remove more material faster, even with less material removed per tooth. For example, my 45cc tanaka with an 18" bar will travel through a piece of 16" oak faster than my 65 cc husqvarna will with the same length bar and same 3/8 pitch full comp. Full chisel chain. This is because the tanaka is turning at 14,000 rpm while the husky is only turning at 8,000 rpm. The chain moves slower even with the bigger saw so it moves through the piece of wood slower.
But there are ways of changing the chain speed and the options are numerous. The easiest, but not necessarily the best when done alone, is to put on a different rim or spur sprocket with more teeth. The teeth are commonly referred to as pins. If you have a 7 pin then put on an 8, you'll notice the difference immediately. But the problem is your saw might not have enough power for this. It's just like changing sprockets on a motorcycle or dirtbike.
If your saw is equipped with a safety chain you can switch it to a full chisel, that will make a noticeable difference. But beware of kickback.
If your really ambitious and have mechanical skills you can gut your muffler and retune your carb. As long as you don't have a limited ignition coil you will gain a substantial amount of rpms by letting the motor breath easier and gain power which may allow a larger sprocket and even higher gains in cutting speed. But keep in mind that the carb must be properly tuned so you don't burn out the piston or cylinder and you could void a warranty.
These are the methods the pro's use. Make more power and more engine speed and gear up the sprocket to utilise that power. I own a 95cc husqvarna that usually totes a 42" bar turned by a 7 pin sprocket. Not the fastest cut but pulls through a long cut. Once in a while I find the need to put on a 20" bar and turn the 3/8" pitch full comp chisel chain with a 9 pin sprocket, runs through hardwood like a knife through butter. Last time I timed a cut on a 18" dia. Piece of 2 year seasoned white oak it averaged about 4 seconds a cut, and all I had was a normal off the shelf Oregon chisel chain and the rakers where only at .025"
Back to the original point. use the files to touch up in the field, use a proper sharpener when the day is over to restore your chain to its proper shape. I've compared the harbor freight unit to a $200 namebrand unit and the chain cuts just as well. So for the cost of a summer worth of files you can have an electric grinder that will most likely last for quite a few years. Because if you sharpen properly, you will do it less.
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Topic: a word on chain sharpening.... (Read 6730 times)