Odd situation : only half of chain teeth beat up

[frogpond]

I went to sharpen the chain on my Stihl ms261cm after it got dull( probably hit some dirt while bucking up a maple). Only the teeth pointing one way had ragged cutting edges, while the ones pointing the other way were just a little dull, but undamaged. What could hsve caused this?
It's a Stihl semi chisel 3/8 chain on a 20" lightweight bar.

 

[4570Man]

It’s pretty common for chainsaw chains to just get damaged on one half. A gravel stuck in the bark could have easily done it.

 

[Hay Dude]

I have had this happen and found something stuck under the removable sprocket drive cover.

 

[Runner]

Happens to me all the time, hit a rock, nail, piece of fence wire with the bar tilted to one side and it only dulls the teeth on that side.

 

[ruffdog]

Years ago I found square nails deep inside an old oak.

 

[Runner]

The worst of it is that now you will have to sharpen those teeth more than the other side and will wind up eventually tossing a chain with only half the teeth worn out.

On the brighter side, the difference in size of teeth doesn't really affect the cutting or tracking of the chain...

 

[Rockbadchild]

happens all the time, the debris was on that side or its simply that side that caught it. Is you rakers files down the same ? that's could impact this if it's not the case but then your saw would cut crooked as well.

 

[frogpond]

Oh well, so much for my theory about one-armed gremlins...
I file all the rakers the same. I use a Stihl 2in1 for filing, and also round the leading edge of the rakers after a while. After this occurrence, I filed all the teeth to the same size, of course.

 

[Rockbadchild]

Oh well, so much for my theory about one-armed gremlins...
I file all the rakers the same. I use a Stihl 2in1 for filing, and also round the leading edge of the rakers after a while. After this occurrence, I filed all the teeth to the same size, of course.

I don't do that... I file it until its sharp and stop, yes I end up with some teeth longer then others but next time it could be the long one that get hit...

 

[Jrasband]

Oh well, so much for my theory about one-armed gremlins...
I file all the rakers the same. I use a Stihl 2in1 for filing, and also round the leading edge of the rakers after a while. After this occurrence, I filed all the teeth to the same size, of course.

I also use the stihl 2in1 and find it excellent.

I disagree that it is necessary to sharpen the teeth evenly, I think you are wasting material, time and chain life by doing so.

 

[ruffdog]

I also only sharpen until it is sharp...not until it is even with the other teeth.

 

[nebraskasparks]

I used to do the same thing until I read Stihl’s sharpening guide material. After reading the guide I went out and took 7 old chains and sharpened the chain including taking down the depth gauge accordingly. The difference between sharp and awesome came through loud and clear. If you want to see chips fly like butter - do it by the book

Sharpening Chainsaw Chain | Oregon Products

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