Chainsaw: Unhappy with sharpness!
I have always been unhappy with how "sharp" a chainsaw chain is. It is quite disappointing that as we near the decade mark of the new millennium that chainsaw chain manufactures could not get a decent edge on a new saw chain right out of the box...one must hand file it to get it reasonably sharp first. But even then I wondered could you up the chainsaw sharpness ante up without spending a lot of time and yet have some longevity to it as well. I mean what is the point to get it super-sharp and yet have that crisp edge disappear by noontime?
I always noted that a chainsaw chain has a flat spot on the back side of every tooth. I wondered if that might be the answer to the holy grail of loggers, a super sharp chain that would last quite awhile? Well today I had some time (babysitting my daughter) so I tried a new method. First I had a new bar and chain on my saw, then hand filed that new saw chain so it was decently sharp. Then I took a small fine-grade sharpening stone and stoned the back edge of every tooth. A magnifying glass seemed to show a much smoother edge, so I took a diamond file and further flattened the back of every tooth. In theory it should have been the equivalent of filing the backs of our plane blades and chisels. It took me an additional 5 minutes to do this...no big deal really if it worked.
I did a series of test cuts on wood and I am convinced it is much, much sharper. The saw never stalled the chain once, and the cuts left no ragged edges from the cut. This was an improvement, but obviously the cutting edge was not really being tested...the standard height raker was only feeding the tooth x amount of wood. Yes my saw was not laboring, but I was not really going from point A to Point B any faster.
So the next check was to see how much of the raker I could file off in order to make a bigger chip and see if the saw, with its ultra sharp saw chain, could pull out of the wood without bogging down. Well a pretty darn big chip! I swiped each raker with a coarse mill b@stard file twice and the saw was blowing some pretty big curlie ques out the other side when I did another test cut. In fact it looked like I was ripping and I was making a cross-cut, the chips were that big!
I am definately happy with its new performance!
I guess the only way to really up the ante now as far as sharpness goes would be to put a slip stone 7/32 in size along the bevel of each tooth and really smooth out the file marks on the tooth. Between that and the flattened backs of each tooth, your chainsaw would be like having 66 3/8 chisels along its bar!
I don't think I found the Holy Grail of chainsaw sharpness yet, but I think I found the trunk it resides in.
Last edited by Travis Johnson; 05-27-2009 at 02:01 PM.
I have no intention of traveling from birth to the grave in a manicured and well preserved body; but rather I will skid in sideways, totally beat up, completely worn out, utterly exhausted and jump off my tractor and loudly yell, "Wow, this is what it took to feed a nation!"