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Saw keeps getting pinched

Cromwell

Cromwell

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Apr 1, 2020
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21
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United states
Professional climber here.
It was the 201 that only I use. The chain (new last spring) was sharp but if I cut through anything 6" or thicker it would start to get pinched. I always file down the burrs, so I know it wasn't that. Anyway, someone broke the chain on our other 201, so when the boss got a new chain I stole it for my saw and passed my chain down. Problem solved.

So even though the chain was sharp, and the bar is straight and free of burrs, it cut like garbage until I replaced the chain.

This problem is starting to show up again in some of our ground saws too.

My question is:
We've got some new guys on the crew who are green and eager. Is it possible that, when they try to sharpen the saws, they're ruining the chains irreparably? Maybe, somehow their angles are thinning the kerf or something. Never experienced this. Our foreman is confused too.
 
Vintage Engine Repairs

Vintage Engine Repairs

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If it’s been sharpened unevenly, once side sharper than the other, or depth gauges lower than the other the chain will pull to that side, it’s not until you are a little way into the cut it can stop cutting completely unless you fight it constantly.
 
MagraAdam

MagraAdam

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If it’s been sharpened unevenly, once side sharper than the other, or depth gauges lower than the other the chain will pull to that side, it’s not until you are a little way into the cut it can stop cutting completely unless you fight it constantly.
I was about to post this exact thing. It's happened to me when not being careful with my depth gauges.
 
Bob Hedgecutter

Bob Hedgecutter

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Jul 18, 2019
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Small Town, way down South- New Zealand.
Professional climber here.
It was the 201 that only I use. The chain (new last spring) was sharp but if I cut through anything 6" or thicker it would start to get pinched. I always file down the burrs, so I know it wasn't that. Anyway, someone broke the chain on our other 201, so when the boss got a new chain I stole it for my saw and passed my chain down. Problem solved.

So even though the chain was sharp, and the bar is straight and free of burrs, it cut like garbage until I replaced the chain.

This problem is starting to show up again in some of our ground saws too.

My question is:
We've got some new guys on the crew who are green and eager. Is it possible that, when they try to sharpen the saws, they're ruining the chains irreparably? Maybe, somehow their angles are thinning the kerf or something. Never experienced this. Our foreman is confused too.
Or maybe you had a loop of narrow kerf chain on a standard bar?
 
Bwildered

Bwildered

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May 26, 2015
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33' South
It can be caused by a different hook angle, its caused by the natural differences between forehand and backhand filing, I'm guilty of it, i used to file 1/2 a dozen times a day when falling and could do it just about blindfolded, now have to wear glasses & pay particular attention to the backhand filing depth of the tooth because I was getting too much hook & eventually my cuts wouldn't line up, combine that with cheap chains and bars & it's hard to get them cutting good again.
 
lone wolf

lone wolf

MS 200T King
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Oct 5, 2009
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60,423
Location
Prowling The Pine Barrens
Professional climber here.
It was the 201 that only I use. The chain (new last spring) was sharp but if I cut through anything 6" or thicker it would start to get pinched. I always file down the burrs, so I know it wasn't that. Anyway, someone broke the chain on our other 201, so when the boss got a new chain I stole it for my saw and passed my chain down. Problem solved.

So even though the chain was sharp, and the bar is straight and free of burrs, it cut like garbage until I replaced the chain.

This problem is starting to show up again in some of our ground saws too.

My question is:
We've got some new guys on the crew who are green and eager. Is it possible that, when they try to sharpen the saws, they're ruining the chains irreparably? Maybe, somehow their angles are thinning the kerf or something. Never experienced this. Our foreman is confused too.
How sure are you the bar is straight did you try swapping a new one or a known working well one? Thats what it sounds like to me.
 
Ripandsplit

Ripandsplit

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Nsw australia
Sounds like uneven bar rails or worn bar groove. I close my bar grooves up as apart of regular preventative maintainence. Might be worth a look . Good luck safe climbing
 
Ripandsplit

Ripandsplit

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Nsw australia
Sounds like uneven bar rails or worn bar groove. I close my bar grooves up as apart of regular preventative maintainence. Might be worth a look . Good luck safe climbing
Sorry being a bit vague in my last post . To much lay on the chain to the left or right off center can cause these problems you describe . I aim for as close as I can with out pinching thw drive link to avoid burning up bars . Alternatively uneven bar rail tops will cause the same symptoms although not as noticeable with a new chain due to the width of cutting kerf. Regardless of pitch and gauge. I close my rails up with a piece of railway line and an engineers hammer. Using a feeler gauge to check gauge . And a bench linishing wheel to dress my bars . Good luck .sorry for the ramble hope you find the answer. Nothing worse than a dull saw or one that doesn't cut straight.!
 
Alleycat

Alleycat

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Sep 20, 2005
Messages
56
Location
Central Mississippi
What about a bent bar? I made some cuts the other day and they all hooked to the right. I checked the chain and all teeth were the same length. Took a look at the bar and it is bent between 1/16" to 1/8" . IMG_1873[1].JPG IMG_1871[1].JPG
 
cookies

cookies

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Crawfordville
chains/bars/sprockets are all wear items, used every day they need to be cleaned/ inspected closely at the end of each day and replaced or properly reground when they show signs of uneven wear. First you need to learn the chains correct movements and how it is supposed to sit on the bar during cutting then you can tell in handling what is worn beyond what safely useable. Any time something is questionable I replace it for my own safety(and those around me) and ease of effort on my hands and back. The first time you have a chain derail, break or jam in a seriously dangerous moment you get hit with a sense of fear of what you are doing, never forget that feeling.
I had a chain that was sharpened unevenly on a worn bar (that came on a used saw) that cut to the right, half way through a 10" branch it started to pinch, I slid the bar out at full rpm to keep it from getting stuck. When the bar came out the chain broke and was ejected at high speed. Now when something is causing angled cutting, binding, chatter etc I change saws and later on I fully inspect the chain section of the saw and replace anything thats beyond simple repair methods or questionably worn. My safety is more important than a 100.00 bar/chain/sprocket setup.
 
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