Unhardening chainsaw chain

[Abner]

I have used a grinder on some of my saw chains and now they are too hard to use a file on. I know the process involves heating. Could I use a simple hand held torch and what color do I need to bring them to so I can file them?

[JoeLee]

Spare yourself the headaches. Get a 1/8" thick grinding wheel, radius the edge and dress the inside gullet of each tooth. They don't have to be perfect.
I use a 4" disc on my Metabo. I don't even have to take the chain off the bar to sharpen it. I never found any rat tail chain saw file that would cut the teeth of a chain.
If you try to take the temper out of the chain you'll probably never be able to harden it back to where it should be. A soft chain will dull and stretch faster than it normally should.

JL...............

[MattiJ]

250-300 cel or so should result bit under 60hrc.
violet to dark blue.

Note that you need new and good quality make file for the harder chains like Stihl chains.
And remember a file is not a toothbrush, don't press the file on return stroke..

[754]

It's been a few decades.. but..
We're the teeth hard..yeah sort of..
We're you able to file them thru the life of the chain..yep..
Use a good file I used Sandvik I think..

If you insist on using cheapo files, stop wondering why its so hard to get work done..

[LKeithR]

...If you insist on using cheapo files, stop wondering why utsxso hard to get work done..

Amen to that. I've sharpened saw chains probably thousands of times over the past 50 years and I've never had problems
with filing them. Never once used any kind of grinder. And if your chain is that bad just replace the darn thing--they never
work as well when they get down to the nubs. Here in Canada Princess Auto has replacement chains for very reasonable
prices; gotta be similar sources in the States...

[Dan Dubeau]

Get a new file, get a new chain, or just continue to grind that one until it's life is over. I can't see annealing it doing anything but drastically shortening it's life.

By any chance did you try and grind it using a round diamond burr in a dremel? Wonder if its somehow diamond impregnated slightly which is causing the file to skate. I can't see grinding it with a stone making it harder. If anything it would be the other way (excess heat build up).

Anyway....I can think of much better ways to spend my time than trying to anneal a chainsaw chain that wont file sharpen, but if all you got's is time, have at er.

Thanks for reminding me to sharpen a couple chains. Got some cedars to limb this Sunday as I can finally get back to them.

[BCRider]

Hard use of a grinder would have heated the teeth and made them softer, not harder. So tempering them isn't going to help anything at all.

I'm thinking that there's something to Dan's idea that if you used a grinder with a cheap diamond tip that it may be leaving some of the diamond in the teeth. So that just means you need to keep using the same grinder.

I've not sharpened a chainsaw much. But I do know that the teeth are hard enough that it's important even with a good saw file to use firm, slow strokes. Nothing stresses the basics of using a file correctly like filing a harder steel such as chainsaw teeth. If you're too light with the pressure or try to do it too fast the file will skate and dull rapidly. Same with releasing the pressure for each return stroke to again avoid dulling the teeth.

[ahidley]

Get one of these

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F152866614899

Chain saw chains are magnetic . They attract every nail, bolt or stone in a tree, near a tree or under a fallen tree.

Above someone said that when a chain has been sharpened a few times they just dont cut. The reason for this is due to the little bump in front of the tooth. Grind that bump down until your saw does not produce enough horsepower to cut then add little back!
Ive put big bore kits on all my saws and my chains use ALL the horsepower available. And I DON'T push down at all. The chain bites it and throws noodles of wood chips not saw dust.

[BCRider]

I was assuming that the tooth limiters were being filed down as well.

And yeah, it's a wondrous thing when those noodles of green wet wood are flying. When I start to see larger flakes that's OK too. But when I see finer chips then I know sharpening is at hand again.

[Black Forest]

Get a good file spe ifically for saw chains. And get the correct size file. Don't let your chain get very dull at all before you sharpen it. Make surs you dress the rakers also. Use a flat file.

[Abner]

Ok, I used NEW files. can't remember the brand - from the saw shop. Most teeth file just fine and then I get one that a file won't touch, changed files no luck there. Took it to the grinder and let it have that one. Guess I will stay the course or throw them in the trash. Thanks.

[BCRider]

Ah.... That's different. So the cheapest chains you could find? I'm not judging. Hell, I'm as likely as any to buy the lower cost option.

But I'm going to guess that a tooth or two did not get correctly tempered back to allow it to be tough yet still soft enough to sharpen. Or there's some manner of hard spot or inclusion in the metal that is harder than it should be. If you were to mark those teeth you could take a propane torch on low to them and bring them to a near blue color to see if it helps. But you'll need to clean the chain really well first. Bar oil on them would hide the true color. And if/when you degrease them don't use brake cleaner then hit them with a torch. Same reason not to use brake cleaner around anything being welded.

I've used some chainsaws belonging to my clubs and other folks on and off and only recently bought a nice small Stihl on sale. I've not run into this issue myself but I think it's a good reason for buying a slightly better name brand from here on in.

[754]

Sometimes a few teeth get Rocked, they flatten and maybe curl slightly.
Now the file does not fit properly in the radius, until the high portion of the burr comes off. Then it will again feel likevtye other teeth. I always wipedvtge file often against my chaps or glove to get the filings off.

You will learn, it takes practice.. and Then and Only Then.. you can sing the Lumberjack Song honestly.....
...a lot of posers sing it..

[Abner]

Ah.... That's different. So the cheapest chains you could find? I'm not judging. Hell, I'm as likely as any to buy the lower cost option.

But I'm going to guess that a tooth or two did not get correctly tempered back to allow it to be tough yet still soft enough to sharpen. Or there's some manner of hard spot or inclusion in the metal that is harder than it should be. If you were to mark those teeth you could take a propane torch on low to them and bring them to a near blue color to see if it helps. But you'll need to clean the chain really well first. Bar oil on them would hide the true color. And if/when you degrease them don't use brake cleaner then hit them with a torch. Same reason not to use brake cleaner around anything being welded.

I've used some chainsaws belonging to my clubs and other folks on and off and only recently bought a nice small Stihl on sale. I've not run into this issue myself but I think it's a good reason for buying a slightly better name brand from here on in.

Hm, never thought I was a cheap. I buy 100' spools of OREGON 3/8 full chisel skip chain and make my own loops for my three Stihl chainsaws.

I will try the torch trick. Or toss them out.

[BCRider]

If you don't think that they qualify as cheap then I'd talk to the supplier or maker and tell them of what you've found. It sure doesn't sound right to me.