bar problems - and prevention?

[Engineer]

Bear with me here, it's probably insignificant in the big scheme of things but I want to know if this is "normal"....

I have a Stihl 025.  About 15 years old.  The Stihl bar that came with it got fitted to a Log Wizard debarker and so I went online and bought a 16" GB PowerTech bar for it.  Been running a variety of Stihl, Oregon and Woodsman Pro chains on it, all of them standard .375 x .063 - 62 DL.  Flip the bar over once in a while, not according to any schedule.  It's not abused but it is well used, I've worn 75% of the paint off the bar.

Couple of days ago I was out cutting some firewood and noticed that the saw would "hang" in a cut.  The chain would be running full speed at full throttle but the bar wouldn't drop through the cut.  Like something was physically holding it up.  It would make a bore cut just fine, and rocking the bar made it go again.  I had a brand new, just out of the box Woodsman Pro chain on it.  The saw had never done this with an old chain.   Well, yesterday it was doing it some more, so I quit early and pulled the bar and chain off the saw.  First I noticed that the whole thing, bar, chain and sprocket, were HOT.  Too hot to handle with bare hands.  Not normal.  Then I got to closer looking at the bar, and discovered that the bottom of the bar was mushroomed out away from the groove for almost the whole length of the bar, like someone had taken a hammer to a rivet and rounded it off all the way down.  Even up into the tip at the sprocket. 

Now I don't inspect my bars carefully but this is the only bar I've run on this saw in 6, maybe 8 years.  I have flipped it before and haven't noticed any damage.  So I have a bunch of questions now -

Is this normal for that kind of damage to occur?  Could the chain be that much harder than the bar, that high speed, friction, pressure and heat would cause it to mushroom like that?  Can it be fixed with a bar closer and a file?  Or is a bar considered "disposable" and should I just get a new one?  I'd be concerned that if I tried to close it and file it, the groove would be shallower and cause the chain to run along the bottom of the groove (causing more problems). 

I run a couple different bars on my other saw - it's time to check them too, I guess.

[olyman]

some bars are hardened not too deep on top of the rails--and when you punch thru--they wear really fast--could be your case

[Rocky_J]

We just had a bar thread here last week, lots of good info. I won't repeat myself so soon but maybe you might find something useful there.
https://forestryforum.com/board/index.php/topic,33310.0.html

[tyb525]

Those are burrs that are formed, which is normal. You should file those off regularly. before they get that bad. They are what "hold" the saw from cutting through the wood. Also, make sure your bar is getting enough oil, and check your chain tension.

[Rocky_J]

My rule of thumb on chain tension is "no sag, no drag". Most inexperienced users (and a lot of more seasoned folks) tighten the chain too tight. Usually because the chain isn't as sharp as it should be and so it gets hot and stretches out, therefore the user thinks if he overtightens it then it will be longer before he has to tighten it again. You should be able to spin the chain easily by hand when it it tensioned properly.

[thecfarm]

Looks like you got your moneys worth out of that bar.  :D I never had one wear like that.Most of the time the tip goes first on mine.Just the way that one wore out I guess.

[sawmilllawyer]

I think that its time for a new bar. At this point that bar don't owe you nothing. Sounds like the hardened steel was plumb wore off.

[Ed]

Another vote to go buy a new bar.....it's time.

Ed

[Engineer]

Thanks, y'all.   :-\  Sounds like it's time.  I am a little frugal when it comes to that kind of thing, my dad still has his old Homelite Super XL that he bought new in 1966, with the original bar AND chain.  I guess I take after that.   I just never figured, even with owning a sawmill, that I'd ever need to replace a bar unless it got severely damaged, like bent or pinched.

Then I think about how much money I'm saving by burning wood instead of buying oil and I think that maybe it's worth NOT pinching pennies.   :D ;D   Since I feel obligated to justify every purchase with my dear wife, telling her that the couple of grand we save in heating oil every year can buy me some decent wood processing equipment makes it easier for ME to stomach as well.

New bar it is.  I'm still gonna try to salvage the old one, just in case I pinch a bar and I have to swap 'em out on the tree.  :(

[Rocky_J]

How often do you change your sprocket? Worn bars and sprockets rob a lot of power from the chain. With a fresh bar and sprocket you will be amazed at how much easier the saw cuts.
8)

[SawTroll]

I file any sign of "wire edges" off as soon as I notise them, usually inspect for them at the same time that I flip the bar.

GB Power-Tech bars have a spotty reputation, at best.........

[joe_indi]

I have seen quite a few bars with the same problem.In all the cases they were  ruined by accidentally running  chains having thinner drive links(0.58 or 0.50).

The thinner drive links tend to tilt in the cut, pressing outwards on the upper edges of the grooves.This causes them to open up.
In 90% of such cases just hammering the grooves back to shape would  not help because quite a bit of metal also is removed by the thinner drive links.
The next time you buy a bar, I would suggest you go for one with 0.50 groove width.Your 025 can take such a bar.When you have run 5-6 chains  on the bar, move on to chain of 0.58 dl thickness.
If you bar still survives it would finally be able to take 0.63 dl.
This will save you quite a bit on guidebars.
I suggest this to customers for  Stihl Pro-saws and it really works.They start with 33RSC chains,on a bar of 0.50 groove width, move onto 35RSC and finally use 36RSC before buying a new bar.

Joe

[Engineer]

GB Power-Tech bars have a spotty reputation, at best.........

Never heard that before.

Any recommendations?

[Rocky_J]

I've been running GB bars for about 4-5 years on all of my midsize saws and I like them a lot. Stihl branded bars may be a little bit better but they are much more expensive.

[woodmills1]

I file burrs off all the time.  I also keep a piece of broken hack saw blade in my tool box and use it to clean the crud out of the bar groove, I use the back of the rounded end of the blade it pushes the crud out easily.