Twisted Roller Chain

[Rougespear]

I'm switching the drive chain on my sawmill.  When I install the new chain (all 50-odd feet of it for each side) there is a twist in it of almost 90 degrees as the chain travels between two sprockets.  Does anyone know why, or anything about this?  Is it bad chain (i.e. twisted over the 10' lengths) or bad installation?

Thanks

[ozarkgem]

maybe a pic would help. I cannot feature a roller chain being twisted on purpose

[kelLOGg]

I vaguely recall mine doing that when I installed it 10 - 12 years ago. I assumed it was a quality control issue during manufacture of the chain; perhaps the links on one side were slightly longer than the other. Anyway, it eventually wore evenly and now lies flat. Frankly, I had forgotten all about it until I read your post.
Bob

[Kbeitz]

Sounds like bad chain...

[Rougespear]

Picture posted above to describe issue.  I purchased 100' of roller chain from the same store, all in 10' lengths.  When I hang a length of the chain vertically against a known flat surface, the twist reveals itself in about 3-4'.  Every length of chain exhibits the same way.

Bad chain?... could all ten lengths be bad, or is this truly a case of poor manufacturing?  Admittedly, the chain was purchased from a "cheaper" joint in town.  Can I still use it or don't bother?

[kelLOGg]

What about alternating the 10 ft lengths so that that they twist in opposite directions. Not ideal but it may wear the twist out.

[ozarkgem]

Looks like the chain and sprocket don't match. You could put another sprocket on top and to one side and use some down pressure to make the chain run on the sprocket. I would try some sort of down pressure before I bought another 100' of chain.
   Seems like there are chain tensioners on combines or some piece of farm equipment I have seen.  Just a spring loaded sprocket.
  I guess you really don't need a sprocket at all since it is just an idler. It could be a flat pulley as far as that goes. Mine just lays on the C channel frame.

[Rougespear]

The sprocket and chain are indeed compatible.  I tried figuring a way to alternate the twist to no avail.  I guess I will add a couple more idler sprockets to help hold it.

Ozarkgem: you are correct that I don't need any idlers on one side (the other side must be routed down below the frame to clear the log loader mounting brackets).  My intent in adding the idlers was to take out some of the sloppiness of the chain so its not flapping all over.

[redbeard]

 With all of debris and sawdust idler sprockets might have been a problem keeping the long length of chain straight on my application. PVC has been working really good for me. Been 8 months so far and barley any wear on PVC pipe. Can always turn pipe a bit if wear is a issue.  I used a full roll of chain from Napa cost wasn't bad. Also I have modified chain since picture of chain riding on loader arms it travels freely down that side in Pvc now.

  

 

[ozarkgem]

good idea on the pvc pipe. I would think the sawdust build up would keep it from wearing. Kind of like dust wear plate.

[reedco]

Might try two adjustable wrenches and twist it back just a little every 3 or 4 links.

[kelLOGg]

My chain rides in a 1  x 2 channel, around sprockets and through a pipe with a PVC inserted in it. (Pretty much like Redbeard.) Trying to minimize chain contact with too much steel.
Bob



 

[Rougespear]

Some great ideas here guys!  I do like the PVC pipe idea... although I struggle with imagining how it will go around the loader arm brackets (much like Redbeard's first photo).  I have tried to twist the chain with a wrench with marginal success.  I may try some more, or I may see how it works as-is and go from there.

In the end, I grabbed two more sprockets and trapped the chain between an upper and lower sprocket mid-way along the 22' chain run on each side.  The two sprockets push the chain down lower enough to wear I think it will be out of the way when I add brackets from the loader arms.  If that is not sufficient, then I will move the idlers to the ends and run the chain through 18-20' of PVC pipe.  And Kellogg: I like the u-channel for supporting the upper run of chain - I may try a couple feet of that on top of the loader arm brackets with some UHMW in the trough to guide the drooping upper chain up and over the two loader arm brackets.

I see the Cooks' mills have the upper chain running along the top of the main beam steel of the mill... I would have thought this would introduce a lot of unnecessary wear on the chain.

I try for some pics of my install if I get to it today.