different size drivers

[paul hill]

Put a new bar on a saw and it was just a little bit longer so I had to add a couple of links to the chain to make up the difference. I filed the new teeth and rakers down to match the old teeth (about 2/3 gone) and put the chain on the bar. Now when I roll the chain around the bar by hand the drivers on the new links hang up at the top of the bar as they start over the tip. They are stiff and hard to move around the tip until they reach the bottom of the bar and then roll smoothe again. The bar is a Oregon laser tip solid nose bar and the chain is oregon 72lg if it matters. 50 ga chain on both new and old links and 50 ga bar. Bar is almost brand new. Is this a problem or is it normal? I'm assuming it's just wear on the old drivers vs. the new ones and it will be fine but I thought I'd ask first and cut later.

 

[Fish]

Since it is a hard nose bar, the only thing I can think of is a
little more drag from the new length of chain. It would be more
undrstandable if it was at a sprocket tip or at the sprocket.

 

[mikey]

Hi Paul,You stated that you added links to the chain.Remove the chain to check for binding at the links you added.Its possible that you may have over spun, or over compressed the links you added.The chain should rotate freely at each link.Hope this helps ,Mikey

 

[Greg Carberry]

It sounds like you overspun your rivets or your bar is pinched at the tip a little. Or being a hard nose it might not be worn in yet. The old chain could could have thinner drivers from use. Most likely though your rivets are binding

 

[paul hill]

Thanks, I'll give it a try this weekend and let you know if it works.

 

[Tony Snyder]

Why in the world would you want to run a hardnose bar on a non gear drive saw? It is like going back 30 years.

 

[homelite360]

long hard nose bars rock. like on my homelite 1130g it don;t car weather the chain is a rusted pile of junk or not it will pull it though and eat it for lunch

 

[jokers]

It`s possible that you put a small sideways kink in your chain when you broke it. That would be my first guess after over spinning the rivets. You could probably press it back to close enough to straight with a light touch on the breaker. Russ

 

[paul hill]

Hey Tony, the reason for the hard nose bar is that's what I've been told works the best for my type of cutting. I cut alot of dead oak snags for firewood in the high desert areas. Some of this wood is hollow and has all kinds of dirt, rocks and other debris in it.I've been told by several people both old timers locally and on this site that for hard dirty conditions a hard nose bar is best and for more controlled clean conditions, use a sprocket tip. I don't understand your comment and I'm new at this whole saw thing compared to alot of you so explain your thoughts and ideas so maybe I can learn something new. I also have a couple of sprocket tip bars that are longer and I try to use in good clean wood.

 

[geofore]

pinch point

Did you turn the bar over and run it? Does it do the same thing? This should tell you if it is the bar or the chain with the problem. I can't tell you how many people don't turn the bar over but I see a lot of that when they ask me to fix their saw. They run the chain till it won't cut anymore and not once did they turn the bar over to use both sides of it. If it is still pinching after you turn the bar over, the rivets are the next thing to check, too tight or over spun.

 

[treeclimber165]

Back to the original post, why would someone put a 3/4 worn chain on a brand new bar? Sounds like false economy to me. I've always started with a fresh chain and sprocket when replacing a bar. I'd save any 1/2 worn chains for spares, after the bar was 'broken in' a little.

 

[paul hill]

While I have to agree with your thinking treeclimber, you didn't give me much credit or read my statement correctly. When I bought the new bar I bought several brand new chains to fit it.(from my local dealer) I had one chain that was 2/3 gone from the old bar that I added two cutting links to to fit the new bar. I did break the bar in with the new chains, thats why I said bar is almost brand new. I put the old chain on the new bar so that I could file down the new cutters to the same length as the old ones. I think that is correct. That is when I noticed the problem with the new links. False economy?

 

[Fish]

When I break any chain any more, I grind the rivet heads off
first, as the old punch/press would occaisionally bend a drive
link. But the trouble you describe is hard to picture, as you
have no binding problems at the sprocket. Will the saw turn the chain? Is the chain type/model/etc. identical on both pieces?
Oregon preset and side straps as well.
I am a hardnose fan myself. Most bar failures other than
bending or pinching are sprocket nose related, the hardnose uses
a little extra h.p., and is harder on the bottom of the straps,
but I like mine. But then I only work on them.

 

[Fish]

Why was the thread title, "Different size drivers"?
Are you using a piece of 3/8 l.p.? Something else?

 

[paul hill]

I don't know the reason for the title of the thread? I didn't know what else to call it. I was guessing that they might be different sizes from wear new vs. old. Double checked the chain and all the links are the exact same brand and size of chain. 72lg Oregon, 3/8 .50ga. Does the exact same when the bar is flipped over. I think because several brand new chains work just fine on the same bar that it must be what was said about overspinning the rivets. I'm going to replace the links this weekend and start over and we'll se what happens. Thanks for the ideas.

 

[Crofter]

Wear on chain rails

The new links will be deeper from rivet centre to bottom of tie strap in relation to the old worn links and will appear as a tight spot when it comes up onto the roller nose. try loosening of the adjustmen a bit and see if it runs free. When you put a new link in a worn chain you should grind it down to match. Also the drive tangs may have too be shortened. they also can bottom in bar groove. Hope this helps.

Frank

 

[jokers]

Hi Crofter, good point about the bottom of the drive link needing to be filed to match the others, that is true. I had somehow surmised that he said he had done that already but that isn`t the case, he mentioned filing the teeth to the same length. Good catch. Russ

 

[WRW]

If it is a new bar, there should be no bottoming in the groove. If there is, it's time for another new bar. The pitch should be the same also so it shouldn't matter about the depth of the drivers.
If the rivets are spun too tight, there should be resistance when the new links pass over the sprocket as well as the bar tip.
Fish may have hit on something when he mentioned the bottom of the straps. As the unworn straps pass over the tip, it would slightly tighten the chain.

 

[jokers]

Right WRW, I have to appologize for my mind being all over the place this morning, you said pretty much what I meant to say but I instead babbled something about the drive links, meant the straps, and if Fish pointed this out first, my appologies to him for giving someone else credit.:blush: Russ

 

[Crofter]

WRW you are right about it not bing height of drive links interfering if it is a new bar. I was forgetting what all was in the original post. Have had to deepen bar groove in a worn bar for a new chain though. If the rivets arent tight i'd sure look at the difference in height in the new tie straps compared to old ones. I can understand having a decrepit chain around for such times that you KNOW you are going to cut nails, sand etc. but its better to also have a worn out sprocket and bar to go with it

Frank