sawchain sharpening with bench machine
After all summer filing my own chains it was time to have them done professionally. Not wanting a 60 mile roundtrip to the usual place I checked in town...Yep, Ace Hardware does them. Guy at the weekly breakfast and BS session says "yep, and they do a good job".
Okay, I have now cycled 5 chains through there. Tried out two of them today. Both did not cut as well as when I file them (but at least the teeth were even). Okay, sez I, I'll touch them up when I get home.
Nope. First one (and only so far) that I tried it was like laying a file on glass, no 'bite' at all. Teeth not blued though.
Question. Can I grind them back past the hardening point or does that go waaaayyy back on the tooth?
Harry K
Hi,
I just kinda glanced at the replies so, I may be repeating some info.
Sawchains can be damaged easily by a bench machine. I had a shop for 8 years doing a large amount of machine sharpening myself in central Texas.
The most common mistake that mechs make with a machine is to let the stone get dirty (oil deposit) and leaving the stone on the cutter too long. Both cause the same result. The temper of the metal is changed from overheating. Although the metal is harder to file, the cutting edge will not remain sharp and in some cases may even be curled (use magnifying glass).
The sharpened edge should be silver to chromed in color. If there is any bluing (blue color) of the metal, it has been overheated.
CHOOSE YOUR SHOP AND MECHANIC WELL WHEN YOU HAVE GOOD CHAINS TO BE SHARPENED BY A BENCH SHARPENER.
I would have $1 sharpening specials and would be at the bench sharpener all day long. Even a correctly sharpened chain will be difficult to run a file through for the first stroke or two because the stone does not make a circle like the file. The first couple of strokes will reshape the chain.
Most shops sharpen at 30 or 35 degrees. Have them sharpen one at 25 degrees and see if it doesn't stay sharp longer.
All damaged metal must be removed from a cutter for it to cut properly and remain sharp. Once again, inspect the cutters with a magnifying glass. After a while, the glass will be unnecessary, but it certainly helps at first.
The sharpening should no go so deep as to touch the rivets. This will cause a hook appearance to the cutter and can cause it to catch and break.
There are other factors also, but you can see now that just having the grinder to sharpen a chain does not make a mechanic reliable to trust your expensive chains to sharpen.
It can not be called a talent, but there is a certain amount of training and patience required to properly sharpen.
Good luck,
echoman
Good luck,
echoman