I just had my chainsaw (a 16" gas-powered John Deere) chain sharpened … and now the saw cuts on a curve.
I’ve been bucking firewood logs, making straight downward cuts. But the saw won’t go straight down. It gradually trends to the right as it goes down, and I end up with a curved cut.
Any idea what’s going on? The chain is tight, the oil tank is full, and the engine is running smoothly, near as I can tell. The bar seems straight and undamaged (the saw’s not even 2 years old).
If it was a one-off, I’d blame it on a stubborn bit of timber, but if the same effect is happening no matter what you cut and no matter what direction with respect to the grain, it pretty much has to be an uneven set or sharpening on the teeth.
Has this happened right from the moment you got the resharpened blade back, or have you been unlucky and hit an embedded stone or dirt pocket in some log you have subsequently cut? - if the former, I’d haul it back to the shop and get them to redo the job.
Nope, it’s cut after cut, and I didn’t hity anything funky. Damn! I’ll have to take the stupid thing back.
If the saw started banana cutting the minute you brought it back from the shop for sharpening, they did a crappy job. If you’ve got a Dremel tool, you can buy the stones and guide pretty cheaply, and save yourself some money and the aggravation of somebody else’s shoddy work.
It can also be a problem with the bar. A warped bar would obviously cause it and can be checked with a straightedge. But also common is the groove in the bar can widen out, letting the chain wobble and therefore causing curved cuts. Try wiggling the chain side to side at the bottom and compare how far it moves against the front tip. Replacement bars are fairly cheap.
True, but a well-sharpened chain should not produce consistently curved cuts even with a rather worn bar. I’d strongly suspect a bad sharpening job.
Yep, bad sharpening job. The teeth on one side are cutting better than those on the other. All the teeth should be the same length and all the depth guages should be allowing the teeth to remove the same amount of wood.
my saw was cutting circular to the right, i assummed i had got off on my sharpening or warped the bar. i bought a new bar / chain combo… the saw cut circular to the right from the 1st cut… only thing left to change out or file would be the drive sproket… anyone run across this type of problem?
I’ve never had this happen with a new chain. The only time I’ve ever had it happen, refiling the chain seemed to cure it. When I do refile the chain after a curving cut, I usually find two-three teeth that are facing one side that have been dinged. It seems to me like it only takes a few dinged teeth to cause the problem.
When I file a chain, I have to be mindful to be as diligent to file the second side as I was on the first side. I tend to file the side easier to access with my right hand first and then get tired and hasty when I do the other side with my left hand. That will lead to a curved cut right off the bat.
I can’t imagine why it would happen with a new bar and chain. I would think that any ‘tilt’ imparted by the drive sprocket would get straightened out by the bearing surface on a new (supposedly flat) bar.
Tully, if i ever figure it out, i’ll post! tks for your response…
Are you right handed?
I always start cutting straight cuts and as the afternoon wears on, I find I make more sideways cuts, as my left arm tires and I pull the saw to the right. (Not just pulling, but putting more downward pressure on the handle and across the center axis)
Thats when I know when to stop for the day. Then, the splitting begins!
Maybe the zombie is pulling away as you chainsaw it, causing the curved cut 
Si
Another vote for a bad sharpening job. The teeth on the left are not cutting as well as the ones on the right.
I never have a shop sharpen my chain. I keep a round file and guide in by tool box and give it a quick sharpening when I add fuel and bar oil. At the end of the day i run a a flat file over the followers. When I can’t sharpen it any more I buy a new chain. $20 to sharpen vs $26 for a new chain is not worth the aggravation.