How do you tell if your bar groove is worn to wide?

[jwp]

I don't think that I will be able to get any more good cuts from this bar. I took some vise grips and pressed the grove almost together and it returned to its original position. I also noticed that most of the wear is on the left side of the groove. I guess this is because when felling I let the weight of the saw ride on the bar and the left side of the bar is facing up. I am also guessing that since the wear is on the left side that this lets the chain sit just slightly to the left and that this is what is causing the chain to cut to the left.

When I get the new bar and chain I am going to make some measurements of the groove and drags just so that I will have some base measurements to compare to these old bar and chain measurements.

 

[jwp]

I just got the new bar and chain. The groove measurement and the chain drag measurements are pretty much dead on. .050" + maybe .001" for the bar groove and .050" for the chain drags.

I think that I am going to run a test. I will put my old chain on the new bar and see how it cuts. Is this a bad idea? (I just want to make sure that my sharpening of the old chain was not the problem.)

 

[Philbert]

I will put my old chain on the new bar and see how it cuts. Is this a bad idea?

No. It will help you you understand what is going on.

If you run a really worn chain with a new sprocket (or vice-versa) you will wear the newer part faster. But unless you are going to throw the old chain away (!) there is going to be some 'mixing' of the old and new.

Let us know what you find.

Philbert

 

[jwp]

Thanks. I think that I will get to cut a little tomorrow and I will report back on how the old chain cuts with the new bar.

 

[jwp]

I put the old chain on the new bar and the saw cut straight through a 2 1/2' diameter log. So I am now happy.

It looks like the bar was the problem and now I know that when a .050" groove measures .057" that the bar is pretty much all used up.

The saw cut great even after I had filed the chain uneven trying to get it to cut to the right. It looks like the bar has a great deal to do with the direction of the cut.

 

[garyischofield]

tricky

I've been making my living with chainsaws a LONG time.9 times out of 10, the chain is the culprit.Subtleties in top plate angle,cutter length,side plate angle(hook),depth gauge differences will cumulatively effect how straight the b&c cut.I have used the depth gauge lower on one side trick to try to compensate for a missharpened chain with limited results.It is obvious when filing that a bar groove is getting sloppy.I've seen bars that are so worn they will hunt in the cut if the cutters hit a knot or weird grain.I tolerate that for a while then it is time for a new bar.I have not used vice grips to close the groove but intend to.My blacksmithing skills with a hammer have not had good results on bar rehabbing.When the saw starts cutting crooked ,I pull the saw out of the cut and cut my way back in with the tip.It seems to straighten the kerf enough to have another attempt.

 

[Philbert]

So I am now happy.

I think we have the makings of a new video here, " How JWP Got his Groove Back!"?

Philbert

 

[jwp]

I've been making my living with chainsaws a LONG time.9 times out of 10, the chain is the culprit.Subtleties in top plate angle,cutter length,side plate angle(hook),depth gauge differences will cumulatively effect how straight the b&c cut.I have used the depth gauge lower on one side trick to try to compensate for a missharpened chain with limited results.It is obvious when filing that a bar groove is getting sloppy.I've seen bars that are so worn they will hunt in the cut if the cutters hit a knot or weird grain.I tolerate that for a while then it is time for a new bar.I have not used vice grips to close the groove but intend to.My blacksmithing skills with a hammer have not had good results on bar rehabbing.When the saw starts cutting crooked ,I pull the saw out of the cut and cut my way back in with the tip.It seems to straighten the kerf enough to have another attempt.

I agree with everything that you have said. Most of the wear on my bar was on the left side. I think that this was caused by felling and letting the weight of the saw be supported by the bar. I tried the vise grip trick and it didn't work for me. I hope that it works for you.

Prior to the new bar I was having to make 4 intersecting cuts to slice off a chunk of 2-1/2' diameter wood. I would make 2 cuts from the top and then 2 cuts from the bottom. It looked like a beaver had gotten a hold of the tree. It was also creating extra work for this old guy and that just could not be tolerated.

Philbert, I don't know about getting my groove back. I feel like I turned a canyon into a groove. Maybe the trials and troubles of a misguided chain.

Thanks again for all the help.

 

[Wood Doctor]

However, Consider This...

I've been making my living with chainsaws a LONG time. 9 times out of 10, the chain is the culprit. Subtleties in top plate angle, cutter length, side plate angle(hook), depth gauge differences will cumulatively effect how straight the b&c cut...

Most loggers would also agree for the most part, but recently a logger told me that brand new Oregon 75LGX chain on his bar still resulted in a cut that was pulling to the right and leaving behind a curved cut when working with large diameter logs (say 24" or more) and a 36" Oregon Pro bar.

On the chainsaw forum, another logger just reported the same thing and found that a bar with a groove worn too wide will generally pull to the right, irrespective of chain condition. To simulate the effect, he put a brand new 058 chain loop in a brand new 063 bar. Applying normal pressure to the buck, the saw pulled right in big logs, the top being 4" to 6" off from the bottom. For smaller logs and branches, the error was much less, but it was quite noticable in the bigger logs.

That means a lot for him because the big logs are the "money" logs, and the sawmill measures the shortest length of a log when determining his pay and then rounds down to the nearest foot. He could easily lose $15 on every buck cut that pulls right because some "money" logs are worth $15 a foot or more.

 

[jwp]

Update. It is great having a new bar and chain and an old chain to experiment with. I have been cutting with the new bar and the old chain and things were going great. I decided that I needed to cut some small trees close to the ground so that the stumps would not interfere with driving my truck along the path.

I made a cut into a dead red oak tree that was about 16" in diameter. I made the notch and then the back cut and got the tree on the ground. Again everything seemed great. So now I start to saw the tree into fire wood lengths. This is when the saw started cutting to the left. I make a few cuts with the old chain and then run out of gas so I pack it in for the day.

I decided to put the new chain on the saw just to see if the old chain had developed a problem. The new chain cut straight so I now know that I need to do a better sharpening job on the old chain.

The new chain is not a safety chain and it cuts so much faster and with no pressure being applied to the bar. There is at least twice as much chatter or vibration with the new chain but this is a sacrifice worth making for the increased cutting ease.

The old chain looks good and both sides seem to be sharp but obviously something is slightly amiss with the chain.

Also the new chain cuts a good bit wider kerf than the old chain. I guess that they make different width chains with a 3/8" pitch.

 

[Philbert]

Thanks for the update JWP. Sometimes we never know how things turn out. We all learn stuff from these threads.


Philbert