Thread: I can't cut straight

Are you using a new chain or one that has been re-sharpened?

If it's been re-sharpened, you may need to look at your sharpening technique. In most cases, the most common cause is chain sharpening technique.

Originally Posted by derekh

Not a milling question but a general chainsaw operation question.

Over the weekend I had trouble getting a nice clean straight cut through ironbark and yellowbox. Towards the bottom of the cut, there was a noticeable curve and at one point I needed to prise open the cut to extract the saw.

FWIW: Stihl Magnum 441, 20" bar with 3/8 chain.

What am I doing wrong?

thanks
Derek

I'd say its either a) A very worn bar and/or chain OR b) the wrong size chain (too small) for the bar groove [EDIT] or c) what DJ said.

for b) no comment
for a) Does the tightened chain still flop across the groove like a loose tooth? If so toss both bar and chain away and start with new ones. If the chain is reasonably tight ( just go into a hardware store and try the new ones out for a good idea of how loose it should be) then check the squareness of the bar and dress accordingly. If you have been having this problem for a while then also throw that chain away as it will have worn into a position beyond repair.
For c) a common problem here is having teeth all shorter on one side of the chain which means they don't cut as much.

i second bob.

its either a worn bar or rong chain. unless the chain is sharpend relly badly.

As above Derek, most often it's a bit of over/under sharpenening on one side over a period of time. Eventually it means one side cuts more timber than the other and this leads to the slow curve as yiou get through the cut.

As for the fix, as above, take particular note of what Bob has said, you can't go wrong and his advice will save you time, money, frustration and effort

Thanks for the replies so far. From what I've read here it may be a sharpening issue because the saw, bar and chain are only 5 months old and has about 10 hours. I have all the right gear for sharpening so it's probably my technique then.

Originally Posted by derekh

Thanks for the replies so far. From what I've read here it may be a sharpening issue because the saw, bar and chain are only 5 months old and has about 10 hours. I have all the right gear for sharpening so it's probably my technique then.

Check the length of the teeth. Without realizing it you can easily on average take of a thou' or so more of the ones facing one way than the other. Over time this will accumulate to become easily measurable.

So start by making them all the same as the shortest and then file the rakers accordingly.

As Bob mentioned one side will be longer than the other side. It may not be all the teeth on that side but maybe a third of them.

One thing I found early on with sharpening (I'm right handed) when I was sharpening the left teeth I seemed to take more off in each stroke as the saw fitted under my arms a lot easier this way, you may find the same thing?

Hope it helps

I used to have this problem until I bought the grinder machine for the chain.
Now I can correct my hand sharpening every so often.

also check the rakers length. I had a friend who was bitching that his near new saw couldn't cut butter till i pointed out that the rakers were taller than the cutting teeth. lol.
But my first guess would also be the blades sharpened more on 1 side than the other. I had this very same problem when i first started out using a chainsaw, i found that i tended to apply more pressure when sharpening to 1 side than the other.

5 months dont mean nothing.

i put a new bar on the naibours saw about 2 mounts ago and he braught it don to be sharpend last week. teh bar is compleatly foked the drive links of the chain had chips out of them (somehow).

this is all before the chain had been sharpend once.

just wobble the chain wile its on the bar. it it can move more than a little bit each way (1-2mm) then its buggerd and u need a new one.

Originally Posted by weisyboy

5 months dont mean nothing.

i put a new bar on the naibours saw about 2 mounts ago and he braught it don to be sharpend last week. teh bar is compleatly foked the drive links of the chain had chips out of them (somehow).

this is all before the chain had been sharpend once.

just wobble the chain wile its on the bar. it it can move more than a little bit each way (1-2mm) then its buggerd and u need a new one.

Jee's you have mean neighbors Carl! What he/she the same one that bent your muffler?

The curve cut chainsaw effect can be triggered by just forgetting to top up the bar oil a few times. Combined with less than adequate chain sharpening what happens is the urge to push a poorly cutting saw harder is just too great and users start to hoike a bit harder, Harder, HARDER, on the saw. Whether they mean to or not the user then twists the saw and forces wear on one side of the bar. If nothing is done to correct this, the effect just compounds itself further until you are cutting Crinkles instead of Jatz.

no not the same bloke.

i live amungst a heap of townies that have come out here cose tehy like teh country but can still work in the city.

this particual guy is cluless and his wife recons shee knows everything but knows less than her husband.

i think they might be cutting piles of dirt up with it thow.

Thanks all, I will spend some time this weekend trying to refine my sharpening technique.

I feel you guys must have been watching me at work, because you have all identified things I have been doing wrong. I do tend to sharpen one side better because it feels more comfortable, I've never run it dry but I have run it with a blocked oil channel causing overheating and yes, I do press harder to compensate for a blunt chain. I feel so guilty

My trees often have pipe that is full of termite crap, I can feel the saw stop cutting as soon as I hit it.

cheers
Derek

Originally Posted by derekh

Thanks all, I will spend some time this weekend trying to refine my sharpening technique.

I feel you guys must have been watching me at work, because you have all identified things I have been doing wrong. I do tend to sharpen one side better because it feels more comfortable, I've never run it dry but I have run it with a blocked oil channel causing overheating and yes, I do press harder to compensate for a blunt chain. I feel so guilty

My trees often have pipe that is full of termite crap, I can feel the saw stop cutting as soon as I hit it.

cheers
Derek

Don't feel too bad, Derek

You'll learn that most of the good advice here comes about because of personal experience. In fact, almost every one should come with the letters DAMHIK (Don't Ask Me How I Know)

The other side of that is that most of the advice given here really works