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General Forestry => Chainsaws => Topic started by: CHARLIE on January 04, 2004, 07:55:58 PM

Title: Chainsaw won't cut straight. Need advice.
Post by: CHARLIE on January 04, 2004, 07:55:58 PM
A friend in the woodturning club I belong to, asked me a question which I could not answer and so I'm posting it here for some expert advice.  Thanks in advance, Charlie

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When a chainsaw cuts off to one side instead of straight, does that mean that the teeth on one side are duller than the other? If that's true, on which side would the dullest teeth be to make the cut wander to the right? My theory would be right side/dullest, the sharper teeth on the left would cut better and make the bar veer to the right as it cuts.

Or is it something else, like a worn bar?

The bar looks OK to me, and I use a filing jig to sharpen the teeth on the bar, so I get the same angle each side. It cuts straight when newly sharpened, but after a little while the cut
goes off kilter.

I'm cutting up a bunch of dead elm . That stuff is kinda hard on blades!


Title: Re: Chainsaw won't cut straight. Need advice.
Post by: DanG on January 04, 2004, 08:19:52 PM
Hey Charlie! Where ya been? ???  I wuz about ready ta ask Tom to go check on ya.

I ain't no chainsaw ex-spurt, but my unnerstanding is that it can be either one.  If the slot in the bar gets wallered out too much, it will cause the cut to wander. Also, if the teeth ain't sharpened iggzackly the same, it'll cause the same problem.  Somebody said it was the difference in filing with different hands, that being the right one and the left one, with one being stronger than the other, but I turn my saw around and file both sides the same way. It don't seem to help none. :-/
I'll shut up now, and leave this answer to somebody that knows what they're talking about. I just wanted to say Welcome back from wherever it is you been at. :)
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: CHARLIE on January 04, 2004, 08:39:05 PM
Thanks DanG.  I've been hanging around a little bit but have been gone quite a bit lately.  November was a bad month and I had to make a trip to Florida. Then came home just to turn around and go back down there for Christmas with my wife's family in Okeechobee. Just got back.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Minnesota_boy on January 05, 2004, 03:46:04 AM
I've cut with some bars that were really worn and if the chain was really sharp, they cut straight.  I've used new bars with a chain that was a bit dull and they would try to cut a circle.  The bar should be nothing but a place for the chain to ride in, not something to guide the chain, IMHO. (in my humble opinion)
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Kevin on January 05, 2004, 04:17:56 AM
The bar must match the chain, the cutters should be the same length, the bottom of the chain links should not be badly worn, the bar rails should not be spread or uneven.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: slowzuki on January 05, 2004, 05:25:42 AM
I've been told another thing is the chipper length (cutting edge to back of tooth) needs to be equal all around.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: KDEC19 on January 05, 2004, 09:14:59 AM
I would think that the chain is improperly sharpened.  If one side say the left cutters are sharper the chain will cut better with that side and the cut will be affected.  The chain needs to be sharpened on some grinder that can bring all the cutters to the same size and shape.  whenever my chains start to wander I re grind them on the wheel and it cures the problem.  hope this helps Keith d> :D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: qatanlison on January 05, 2004, 12:03:12 PM
kdec19 is right about the bar drawing toward the side with the sharper teeth. If the teeth seem equal in length check out the bar-groove, if the chain wiggles like a loose tooth throw it in the bin, the bar that is.

/Ola
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: jokers on January 05, 2004, 01:46:43 PM
Another thing to look for is the relative height of the depth gauges. If the teeth are unequal length side to side but the rakers are filed with a guide like the Oregon, the gauges will be averaged and consequently too high for the shorter side. This will give the same affect as one sides cutters being sharper. You may see a similar effect on chains whose gauges have been machine ground. Because of where the wheel contacts the gauges on opposing sides, the gauges will be ground to different heights. If hand filing, pick a direction, ie; inside to out, and file both sides this way.

A chain which has different length teeth side to side can still cut straight as long as the depth gauges are set right and the teeth are sharp. The best tools that I have found to accomplish accurate setting of the gauges are the Husky tool and the Carlton File-O-Plate.

Russ
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Stan on January 05, 2004, 02:58:50 PM
Check the top and corner of each tooth. If they show a chip, they are duller than the others and will influence the direction of the cut. I guess if there are an equal number of damaged teeth on each side the saw would cut straight, but I've never seen that.  :-/
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: tony_marks on January 05, 2004, 08:00:05 PM
  just a guess..could u be getting the cutters on one side
 thinner .. thus causing the edges to break on the dead wood..
a machine should let uknow iif its your filing.. good luck..
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Michael on January 06, 2004, 08:58:56 AM
My idea is take off the bar, inspect it. Is it worn so the drive links wiggle in the slot? Put a straight edge on it. Is it exactly level and both rails even? Check to see if the drive links are hitting in the bottom of the slot. If they do the chain will slant over and not cut straight. I am sure you have already checked for the correct gage. A shop can rebuild the bar and you will be surprised at how good it will cut again. Mike
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: CHARLIE on January 09, 2004, 09:32:14 PM
Thanks to everyone for their help!  I really appreciate it very much.

Charlie
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Oregon_Rob on January 09, 2004, 09:39:23 PM
Charlie,
Got a second chain? If you don't, probably should have. Anyway, find a different chain, new would be best and give it a go. that will tell you real quick if it is the chain or the bar. Or have the shop regrind your existing chain.

Rob
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: CHARLIE on January 11, 2004, 09:34:10 PM
That sounds like a good idea.  It's a friend of mine that is having the trouble and I'll mention  that to him. Thanks!
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: SwampDonkey on January 14, 2004, 12:49:53 PM
Hiya's:

In my experience if your free hand sharpening a chain, use Oregon chains, or similar. These chains have a line etched on the top of the tooth, indicating the angle to sharpen the tooth. Make sure you hold the file level and pull upward with a slight pressure as you draw the file toward you. You shouldn't require more than 3 or 4 draws unless your cutting into fences and hitting the ground or have dirty wood. Check the rakers after 6 or 7 sharpenings to see that they are slightly below the level of the teeth or you'll be rubbing instead of cutting wood. If your teeth aren't sharpened evenly and at the proper angle your going to be cutting in circles.
;D    ;D     ;D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Kevin on January 14, 2004, 04:16:23 PM
Quote
Make sure you hold the file level


Is that the same for chisel chain?   ;)
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: SwampDonkey on January 14, 2004, 04:25:00 PM
@ Kevin

Pondering   ;D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Fish on January 16, 2004, 05:29:01 PM
Drop the file level 10 degrees for chisel.
  Fish
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Mike_Barcaskey on January 17, 2004, 06:25:55 AM
I would think a slightly bent or twisted bar, more so than a bad chain, would be the culprit.
yes/no?
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: jokers on January 17, 2004, 10:21:46 AM
Hi Mike,

I can see where you might think that, but what you would more than likely have with a bent or twisted bar is chain binding and binding in the cut. Cutting "tobbagans" as Gypo would say, happens when one side of the chain is cutting faster. Whether it be due to uneven sharpening or excessive bar wear letting the chain wander to the side that is pulling more.

BTW, nice dead things. Sorry that I can`t tell for sure what they are, but you must be a true "man`s man". LOL  ;D

Russ
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Mike_Barcaskey on January 21, 2004, 06:05:41 PM
jokers, raccoon from this year's trap line
I am lucky to scratch out a living outdoors

On the chain issue, when I first started cutting as a business, I assumed a wandering cut was due to my inattentiveness, as when I paid attention I could straighten it out.

Last summer I noticed one of my bars was bent (no binding)
so I took them all to the machine shop I use to work at. They have a laser checked straight edge made out of a "H" beam.
well half of my bars were bent/twisted.
I assumed this was the cause of any wandering cut

Timely with this thread, I picked up a batch of resharpened chains. The fellow uses a jig and grinding wheel. He is a retired machinist, so I would think he could get it right.

Well one of the 20" chains on my 036 pro was cutting about 3-4 inches to the right thru a 20" white pine log.

The next day I flipped the bar and put a new chain on. It cuts better, not perfect, this time through red oak.

I dont have this problem much, but when I do it upsets me so >:(
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: L. Wakefield on January 21, 2004, 07:06:00 PM
   I definitely had that problem when my chain needed sharpening- it was made worse by my torqueing a little bit to get it to cut- and then it didn't cut straight.

  But I'm still new enough at using a chainsaw that I can hold even a sharp saw wrong and it won't cut straight. I find then I just  have to line myself up right and the problem goes away. It happens when I'm cutting something at a strange angle and I can't see it really well.  lw
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Minnesota_boy on January 21, 2004, 07:18:00 PM
L. Wakefield,
Don't fret about it.  After a couple thousand more hours, it will just come natural.  :D :D :o
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: tony_marks on January 31, 2004, 11:47:20 PM
 speakin o them bow bars .. anybody got a good something they want a trade for one.. idont use it .. noticed it in the truck yesterday.. came off an 650 evl echo.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Neil_B on February 03, 2004, 03:03:16 PM
Something no one mentioned was the oil going to the chain. No oil makes a hot chain and it will cut all crookedy. Had a Stihl that the pump kept wearing out on. Everytime the pump quit pumping, saw cut crooked.

Traded it in for a Husqvarna  ;D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: SwampDonkey on February 03, 2004, 03:26:43 PM
@ Neil_B

;D  ;D  ;D  ;D Good Man !  ;D  ;D  ;D

another still bites the sawdust pile :)

Actually I run a stihl 450 clearing saw, works great after I modified the air filter. Wasn't gettin enough air, cleaned it all the time too. Cursed thing. Now I gots to figure out a way to drive the hornets away while I try to unhook the harness ;)


ekkkk where's the bug dope!!!
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Ron Scott on February 03, 2004, 05:08:47 PM
Neil,
I had a 034 Stihl that had the same problem; the plastic geared oil pump kept wearing out, thus it wouldn't cut straight until replaced.

Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Neil_B on February 03, 2004, 07:18:13 PM
Own a 365 and a 372. Haven't had any problems until I dropped a log on the 372 and cracked the tank assembly  ::).

Ron, I replaced the pump once after a year of running it part time. Lasted another year and was time to change the pump again. Traded it in towards the Husky 365. Didn't bother telling them about the pump either as they didn't want to bother checking it out the first time. They would rather sell me a $70 part every year.  >:(. If I remember right, mine was the 038.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Ron Scott on February 04, 2004, 09:01:26 AM
Yes, it was an expensive part, $65.00 for the dealer to replace it here, and it only lasted about a year with seasonal firewood cutting, just as you experienced. I talked to a Stihl Rep. about the oiler problem since it was always dealer serviced, but without any satisfaction I also traded to a Husky.

Title: Re: Chainsaw won't cut straight. Need advice.
Post by: SwampDonkey on February 04, 2004, 10:43:03 AM
HI Ron:

Yeah most dealers are like that around here too. Take what ya get and buyer beware. Dealers and manufacturers are just too far detached since their on different continents in our case.
I use my Husky 55 for hardwood bucking only. Not heavy or fast enough for production work out on a cuting contract.

cheers
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: OneWithWood on February 06, 2004, 06:34:50 AM
Ron and Neil, I have experienced the same problem on my old 038.  Never had the problem until this last year.  The repair guy at the dealer said the problem was caused by idling the saw with the brake on.  He said heat builds up and melts the nylon gear driving the pump.  At first I thought he was just making up an excuse but then I got to thinking about it.  I began letting the saw idle with the brake on instead of shutting it down after reading a book that suggested it.  That was about a year and a half ago.  So now I shut the saw off before setting it down.  It starts so easy it is not really an issue.  I have not experienced any similar problems with my realtively new MS 440.  I wonder if there may have been a design change.  I engage the brake on the 440 a lot as it is my primary felling saw and I move around with it running more often.  The 038 is my bucking saw, primarily for firewood, so I am more stationary when using it.
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: Neil_B on February 06, 2004, 07:07:21 AM
Can I shorten your name to OWW?  :D

I don't know that that would make sense or not. if the  brake is on then nothing is turning, shaft or pump so where would the heat come from. If from the engine itself then it would make sense that it's much hotter while running full speed.  ???
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: SwampDonkey on February 06, 2004, 01:39:08 PM
Onewithwood

It may be regulation in some areas to engage the break before starting , idling or from walking from tree to tree in the bush. I see it mentioned by different folk lecturing on chainsaw safety, also see it in alot of leaflets. May there was a design change in your model.

cheers
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: wood_bucker on February 23, 2004, 08:42:57 AM
the most comon mistake when sharpening the chain is to make the exact same amount of passes with your file on all the teeth.I have seen people sharpen their saw and skip some of the teeth or make more passes on some teeth that were bad causeing the teeth to become all different sizes which causes iregular cutting of each tooth...also the bar should be flipped over after each major sharpening to get equall bar wear..I have had the same problem in the past cuz..cuzz. i was the guy sharpenig some teeth more and skipping the sharp ones and let me tell ya ..nothing is worse than cutting curves...unless your carving a statue of pam anderson... :D :D :D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: AtLast on February 25, 2004, 04:34:33 PM
I know this has been said but....sounds to me like 1 side is sharper than the other. Just some noise from the peanut gallery ;D
Title: Re: Chainsaw won't cut straight. Need advice.
Post by: vince on February 26, 2004, 03:25:42 AM
always have the same problem with my sawing and believe all thats been said prior. i'm working on a theory that it all starts from those teeth that you plant into the side of the tree and pivot the saw on. the majority of the bar wear is close to this area at the bottom of the  bar. while i can cut clockwise circles when using the bucking teeth, i can cut relitivy straight further out on the bar. i think i always pivoted to much on the teeth with a near dull chain and started all the badness happening. the teeth on three of my saws are only to the left side of the bar and they all do this. just got me a husky 2101 and its got teeth on both sides so i'm interested to see if theres a difference, but i don't have the nerve to start it, yet.

gotta go to work

vince