rim vs spur

[WRW]

Did you continue using the chain that had been thrown from the bar?

 

[pinus]

Yes, continued. Actually I prefer use 3 chains alternatively. In one day usually 2 chains. Half day one and half day second chain

 

[WRW]

OK, pinus. After the first chain was thrown, could you tell, within your rotation, if it was the same chain that continued to be thrown? The reason I ask is that there is the possiblilty of damage that could have perpetuated the one problem and caused the other problem.
I've got to say that my experience has been quite different.

 

[pinus]

OK-OK
Dont remember, was it the same chain or not, but there was some "time inerval" between the accidents.
Wat is yours experience then?

 

[WRW]

OK-OK
Dont remember, was it the same chain or not, but there was some "time inerval" between the accidents.
Wat is yours experience then?

After around 100 cords I changed out the spur sprocket. Never a thrown chain, never any damage to the bar such as you describe. I just have to wonder...I did say that a thrown chain on a rim sprocket would be more likely to damage the chain, didn't I?

I did take a look at the sprocket on that saw. There is some lateral play in it. Then, I ran the chain around the bar and the sprocket remained stationary relative to the bar...no need for any play.

I think that the reason for the rim sprocket floating is so that it will line up with the bar initially after which it remains in a constant position.

Nothing in this discussion should be construed as a preference for one type sprocket over another.

 

[pinus]

After around 100 cords I changed out the spur sprocket. Never a thrown chain, never any damage to the bar such as you describe. I just have to wonder...I did say that a thrown chain on a rim sprocket would be more likely to damage the chain, didn't I?

I did take a look at the sprocket on that saw. There is some lateral play in it. Then, I ran the chain around the bar and the sprocket remained stationary relative to the bar...no need for any play.

I think that the reason for the rim sprocket floating is so that it will line up with the bar initially after which it remains in a constant position.

Nothing in this discussion should be construed as a preference for one type sprocket over another.

That seem to me the same that after some period chain "find" for itself a stationary position on the spur and the chain throwns stopped after that.
However, the bar groove near the spur was weared for the tis time.

 

[WRW]

However, the bar groove near the spur was weared for the tis time.

I've seen this on a rim sprocket, also. I suspect it was the fault of damaged chain, but can't prove it (multiple users and multiple repairpersons before I took over).