Cutting problem

So, I changed back to the 20" 3/8" B/C combo a couple days ago, and now I'm having an issue that I don't know how to fix.
Went to the woods with it today and noticed right away that the saw started pulling into the cut to the right.
When I filed, I noticed the angles were a little off (yep, I did that), so I refiled to fix that somewhat.
I also notice that the chain loosens and droops when cutting, but once out of the cut for a few seconds, it's tight again.
WTH?
This is a fairly new chain with a lot of tooth left.

 

Sounds like the chain is getting unusually hot? Then stretching more than normal? Is that possible?

 

Thought the same Stinny, but the oiler is turned up all the way. I'll fire it up and check.

 

Hehehe, I think I know who you're talking about.
Fired it up a bit ago, and it's oiling, but seemed like it was sputtering. Maybe the bar hole is plugged a little. When I put this one on, the oil port was full of oil, and the 18" deal was oiling well.
I'll pull it apart tomorrow and look/clean.
The bar is about the same age as the chain and not much use on it. I switched to 18" B/C not too long after I got this 20" B/C.
I probably have the cutters all messed up. Pete may be getting some more work soon.

 

If you do send your chain(s) to Pete, I'll be curious if you notice as big a difference as I did.

 

One I say your chain is suspect. Two is the bar worn is the grove sloppy is there metal ridges on the top of the bar that make the top edge wide than the bar itself...this causes it to grab. Also the sloppy grove causes the chain to lay over with pressure causing a turning cut.

And sounds like you may be clogged with chips as well? Chain should not tighten on its own only get loose as the adjustment vibrates out and the chain streaches. As it cools it would tighten but you should not notice that in and out of cuts.

 

When the chain is loose, I do notice the chain rolling in the groove.
I filed the edges before putting it on the saw. Bar groove is clean...I checked before install.
I'm leaning toward the bar being worn, which is weird as it's fairly new. It's a Husky bar. Replaced the original 20" I had on there, and I don't cut very long once it gets loose to avoid opening up the groove.
Maybe I need a better bar.

 

I'd suspect the bar before the chain if it cutting at an angle as you go through the round. The deal with the chain getting loose then tight is a strange one I have never experienced.

 

If things go as planned, I'll be out again tomorrow. I'll keep a real close eye on things.
I don't have a bar closer.....do those work, or are they like a board stretcher?

 

I kind of doubt the groove is opened, but I'd check to make sure the that each edge is level on the bar. That's what I have experienced to make the chain cut sideways. You can usually grind and file it flat.

 

R and R ....... (remove and replace ) the bar and chain

 

That's probably the best plan, but I'm a bit stubborn so don't always do such things right away.

 

Out of curiosity what kind of shape is your sprocket in? Would love to see a pic of it

 

Good point to check out !

 

Try flipping the bar over.

 

All great suggestions.
The sprocket is brand new. Just bought it last year and put it on when I put on the 20" bar a couple days ago.
Not that it can't be worn, but I'm having a hard time believing the bar is worn to the point of the edges being non-level (un-level?).
.050 bar, and I suppose the chain could be wrong. I had it made at the local hardware, but I took the whole thing in there with me to avoid confusion.
I can try flipping the bar.

I try to let the saw do the work rather than pushing real hard to make the cut. I even started the cut with the bar angled in the opposite direction, and it still made a right turn.
I always make the same numbers of passes with the file on every tooth.....both sides.
Would the AV mounts get weak after 7 years of cutting approximately 5 cord/yr.? Difficult to change?
It was cutting great with the 18" (.325) setup, but that chain jumped the bar (I had just flipped the bar and cleaned a little) while in a cut and got some burrs on it, so I changed to the 20".
Changed the sprocket to the 8 pin. I think that's the correct term.

 

Chain of wrong pitch for sprocket can cause the loosening and tightening you mentioned. Incorrect guage can cause the circle cutting. They may have sold you the wrong chain.