# chain and sprocket help



## brown down (Aug 4, 2015)

when attaching chain to a sprocket how tight does the chain need to be? I am chewing sprockets up on my slabbing mill. I will be changing them out to hardened teeth, the ones on there aren't which could be part of the problem! or could it be the size of the chain, its 35 chain on the drive shaft? full throttle she's spinning at about 8,000 rpm at the bar! 

I don't think this is in the correct spot so you all can move it wherever it needs to be


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## woodtickgreg (Aug 4, 2015)

#35 chain is not a very tough chain, and at that rpm.....well you know what the results are. So I would look into hardened sprockets that can also run a bigger chain like a 420 ish or a o ring motorcycle chain would be even better. O ring chains are packed with grease and last longer. And a good hi tack chain lube.

Reactions: Like 1


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## Brink (Aug 4, 2015)

Any pics of the chewed up sprockets?

Time for some parts failure analysis.

Reactions: Like 1


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## brown down (Aug 5, 2015)

they aren't completely toasted but getting close and these don't have that much time on them! I am going to hook a generator up for a biker buddy of mine tomorrow maybe he has some chain lying around he can spare! here are the pics of the sprockets the one with two on them has a brand new one on the upper end off the motor and is still in pretty good shape. the ones going from shaft to shaft are the ones wearing! now how tight do chains need to be? does the chain need deflection like a bandsaw blade does if that makes any sense?


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## Brink (Aug 5, 2015)

Roller chains need slack. Generally, 1/2 the length of a link at the tightest point is sufficient.

Very first pic shows excessive wear
At the sprocket tooth root. That is caused by abrasives, or an over tightened chain. Or a bit of both.

Second pic shows side tooth wear. Causes can be sprockets that are out of alignment, or, in case of verticle shafts, weight of the chain. Guide blocks can help with that.

Reactions: Thank You! 1 | Agree 1 | Informative 1


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## woodtickgreg (Aug 5, 2015)

And it is an undersized chain. Frequent lube will help also.

Reactions: Thank You! 1


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## brown down (Aug 5, 2015)

I literally just got my mill up and running within the past two weeks. I made a few structural changes but nothing on the drive end! the second pic, that sprocket is brand new. I haven't even milled anything with it yet just tuning the saw with the changes I made!! the other one has some time on it but too I think maybe the main culprit was the chain being to tight. would sawdust do that it? I think I have my chains way to tight and way to small and also not the right chain?

I would love to up the chain on the saw but the problem I have is the clutch off the motor is 35 chain


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## brown down (Aug 5, 2015)

woodtickgreg said:


> Frequent lube will help also.



you have any you think of off hand


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## Brink (Aug 5, 2015)

This saw is electric?
How many HP?


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## brown down (Aug 5, 2015)

no its gas and has a 12 HP lawnmower engine driving it!

Reactions: Like 1


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## woodtickgreg (Aug 6, 2015)

brown down said:


> you have any you think of off hand


Motorcycle chain lube is good stuff, several makers of it and it's safe for "o" ring chains. It has a sticky addative so it doesn't fly off. 
I also think centrifical clutches can be had in #41 chain.


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## Brink (Aug 6, 2015)

I'm wondering, why chains, not belts?

Reactions: Agree 1


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## woodtickgreg (Aug 6, 2015)

Brink said:


> I'm wondering, why chains, not belts?


My guess for chains is because of the master link and easier to install. I think he would have to remove the shafts to change belts. But they also make centrifical clutches with belts and v pulleys, even double v pulleys.


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## brown down (Aug 8, 2015)

Brink said:


> I'm wondering, why chains, not belts?



initially I thought It would slip on me and the chains are easier to put on but I think I am gonna switch it out when I cook these sprockets. I would really only have to take 4 bolts out to swap a belt out so it really isn't that big of a deal to switch.. I think for now I will leave the chain clutch on until that cooks and then swap it out!


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## brown down (Aug 8, 2015)

got some milling done yesterday! did a test run on some oak 2'' thick.

Reactions: Like 2


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## JR Custom Calls (Aug 8, 2015)

Need videos!!! haha

Reactions: Funny 1


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## brown down (Aug 8, 2015)

I have a party next week and people want to see this in action, I only have one more log to mill so I will have one of them film it for you guys to see! I need to get up to the mountains and bring a load home but my surgeon said no lol.

Reactions: Like 1


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## Brink (Aug 8, 2015)

Nice tractor @brown down , 1710?


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