046 Magnum Cutting Circles

[mswabbie]

My 046 is not cutting straight. It cuts to the right. I think I have checked everything, but I cannot figure what is causing it. I have done the following;

1. Checked the rubber mounting bushings (3).
All good.
2. Checked the bar for bur;
There was a bur on the bar, I filed it down.
3. Sharpened the chain so the left and right teeth are now equal lengths.
4. Very little wobble on the bar.

After all this was done, the saw is still cutting to the right. does anyone have any suggestions on what to do next. I am running a 24" bar, with a .063 / 3/8" chain.
Thanks in Advance

 

[TonyM]

If the whole length of the bar is following the same arc, I am 99.9% certain it is the chain. If half of the bar wants to curve one way, and the other half wants to curve the other, so that you only can cut a few inches deep before you come to a screeching halt, then I am 99.9% certain it is the bar.

Was the burr on the bar heavily on one side? Are you running full chisel chain? Make sure the teeth are truly sharp, and the rakers are set equally from side to side. Chisel chain can sometimes require a lot of filing to get sharp again after hitting anything other than wood.

 

[mswabbie]

What is wrong with the chain that would cause the saw to cut crooked. The chain is sharp, I have a Oregon 511 A that I use to sharpen the chains.

 

[Lobo]

1- Normally caused by a chain sharpened unevenly.

2- deflection in the bar itself or misalignment off the power head.

Even if you think you have corrected the chain, have you tried with a brand new out of the box chain to see if that corrects it?

 

[TonyM]

Usually when you hit something other than wood, it dulls one side of the chain much more than the other. If you do not remove enough material (especially on full chisel), the chain will not be truly sharp on both sides. The reason I ask about the burr on the bar is that if the burr was heavily on one side (left to right not top to bottom), that suggest the chain has been used often with one side dull, wearing the bar uneven, and now it may help to dress the bar rails.

Try a new chain out of the box in some clean off the ground pieces of wood and see if the problem goes away.

 

[sedanman]

Flip the bar and let us know how it does. I'll bet the bar needs a tune-up. Have the rails ground and de-burred on a Silvey BRG or with a Pferd hand-held fixture. Then check the bar groove width, it can be deceiving before you true up the rails. My feeling is that one bar rail is higher than the other and your chain is laying off to one side in the cut.

 

[mswabbie]

The bur was pretty even on both sides of the bar.

 

[mswabbie]

Thank You all for your help. I will do all that was suggested tomorrow.

 

[TonyM]

Hold a straight edge about 10" long against the bar rails and you can visually see if they are out of square, and if they are leaning the way that your saw is cutting. The rails don't normally wear unevenly though unless the chain is not kept sharp. If you are using full chisel chain, look straight onto the chain towards the saw from the nose of the bar. You should not see any reflection off the point where the side of the cutter meets the top of the cutter. If that point is rounded at all, the chain is not sharp.

 

[tree monkey]

your left foot is heaver ten your right foot. tie a block of wood to your right foot. if this doesn't help try holding your tongue to the right.

 

[glens]

I'm not going to help you if mswabbie stands for microsoft windows abbie!

Crofter posted an attachment in a recent thread talking about bar rails, where he took a file, lifted the chain, stuck the file between the bar and chain at 90° to the direction of travel, then snugged the chain.  When you look at the saw from the end of the bar you can easily see whether the file is at right angles to it vertically.

 

[bwalker]

I worn bar groove can cause the saw to cut crooked as well.

 

[clearance]

Bar is bent

 

[Old Monkey]

Have you got the bar pinched recently? If it was cutting good on Tuesday then turning and binding on Thursday, its a fair bet something happened on Wednesday. If your the only cutter on that saw you should have some idea what happened. Have you checked to see if the dogs are a matching set?

 

[SawTroll]

http://www.arboristsite.com/showthread.php?t=6069&page=2&pp=15&highlight=cutting+circle%2A Have you read this?

 

[mswabbie]

Thanks for your help.
mswabbie actually stands for Old Navy Guy.

 

[mswabbie]

your left foot is heaver ten your right foot. tie a block of wood to your right foot. if this doesn't help try holding your tongue to the right.

I actually used concrete blocks, but kept going under the water. Maybe wood blocks are better. I will try it.

 

[mswabbie]

Have you got the bar pinched recently? If it was cutting good on Tuesday then turning and binding on Thursday, its a fair bet something happened on Wednesday. If your the only cutter on that saw you should have some idea what happened. Have you checked to see if the dogs are a matching set?

The bar has been pinched now that I think about it. What should I look for on the bar. Do I need to spread the rails, or is the bar toast.

 

[galde]

An easy way to check for eneven rails is to stand the (unmounted) bar on its edge on a smooth, hard, level surface. If the rails are unevenly worn, it will lean or tip over. A disc grinder works well to square and smooth the rails. I use a 9" disk with the table at precisely 90 degrees to the disc. Avoid grinding at the edge of the disc. This will maintain a convex profile on the bar. After I clean up the rails, I polish them on a flap wheel. If the groove is straight and of uniform width, and the chain slides freely around the bar, then you shouldn't curve in the cut if your chain is properly sharpened. Another thing to check is adequate groove depth. If the drive links are bottoming out, you can see this on the bottom corner of the drive links and also at the bottom of the groove. I was Navy 1955-1965.

 

[clearance]

Mswabbie- the bar really could be bent, puzzled me before, now I always check. Like with a good 4ft builders level or use another straitedge or if you are in the bush sight it like a rifle.