# How hot should my chain get?



## PortMan (Aug 27, 2011)

When trying to cut through seasoned oak, my the chain on my Stihl 290 is getting pretty hot -- hot enough to sizzle if I spit on it. It's also hot enough to cause smoke to come out of the cut I'm making as I cut through the log. The chain is relatively sharp. 

Is this hot enough to be concerned?

I've verified that bar oil is coming out and lubricating the bar.


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## mtngun (Aug 27, 2011)

If the bar is oiling, then a hot chain is a symptom of a dull chain or of raker issues.


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## Jmaffei (Aug 27, 2011)

I am of the opinion that the bar lube just lubes, it doesn't actually cool anything off. I do think it prevents more heat building up from too much friction but yeah after running awhile in hard wood my chain and bar get hot enough there is no way I'd touch em barehanded. About the only thing you can do is make sure chain is not incredibly tight and crank oiler up all the way if it is adjustable.


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## CTYank (Aug 27, 2011)

PortMan said:


> When trying to cut through seasoned oak, my the chain on my Stihl 290 is getting pretty hot -- hot enough to sizzle if I spit on it. It's also hot enough to cause smoke to come out of the cut I'm making as I cut through the log. The chain is relatively sharp.
> 
> Is this hot enough to be concerned?
> 
> I've verified that bar oil is coming out and lubricating the bar.


 
Dunno what you mean by "seasoned"; what is the MC (moisture content)?
I heard long back that saw chain was designed for cutting green (high MC) wood, for the cooling effect.
As mentioned, I'd carefully check the edges & depth-gauges, and then make them ready for cutting dry wood. (Cheaper than results of mechanical torture.) Smoke while cutting is a BAD SIGN.
While cutting dry wood with sharp chain, take regular time-outs, still running engine to cool engine and pump oil to chain.


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## rob066 (Aug 27, 2011)

I now you say the chain is reltively sharp! Are the cutters evenly sharp on both sides? Are the cutters the same length? Look at the cutters and make sure they have even points! Such as one side sightly bent down and the other side pefectly straight. I have seen a guy sharpen a saw he was good on the right side but would tip his file downward on the left side. It would cut crooked as a bannana. A crooked cutting saw makes extrordinary heat. These conditions above make a crooked cutting saw.


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## WoodChuck'r (Aug 27, 2011)

It should be at least turning the edges of the bar blue and burning the paint off. If it's not doing such you need to turn your oiler down and stop wasting bar oil.


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## 727sunset (Aug 27, 2011)

If your bar has a sprocket nose maybe take the chain off and see that the bearing is free to turn. If there is resistance this could be part of the heat build up.


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## sunfish (Aug 27, 2011)

Yer saw needs some normal maintenance...


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## Chris-PA (Aug 27, 2011)

The bar on my Mac got hot at first too. There were two problems:

1. The chain was too tight.

2. It was sharpened incorrectly. The top of the cutters was sharp, but it had previously been sharpened with a file that was too small. When I used the correct larger file it did not get into the side where the small diameter file had been and that was very dull.

After I fixed those issues it ran normally.


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## pdqdl (Aug 27, 2011)

WoodHeatWarrior said:


> The bar on my Mac got hot at first too. There were two problems:
> 
> 1. The chain was too tight.
> 
> ...


 
I'd go for the chain too tight.

A properly tightened chain does not "snap" back to the bar. At it's tightest, it should still have about 1/8" hang below the bar. The only reason to tighten the chain is to keep it on the bar.

When the chain gets hotter, you need to let it have more hang, so that it won't be too tight when it cools.

When you run the chain to tight, you put huge forces on every rivet with every bend around the 2 sprockets. Despite all the oil in the world, that back & forth bending will create a lot of heat. Furthermore, it wears out chains very quickly!

_Do you find yourself tightening the chain all the time?_ If you are, it's because you are overtightening; the chain "stretches" (wears out each rivet hole) until it has about the right tension...then you tighten it up again.

If you are running a big bar, you need to learn how to run it loose without throwing the chain. My 50" bar will hang 1"- 2" below the bar when it gets hot. If you tighten it up very much, the chain quickly stretches back to that point. Leave it loose and you can go that way for hours without tightening it more. Of course, it's been a long time since I had "hours" of work for that big bar. Usually, it's 15 minutes, and then everything is cut up.


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## 2dogs (Aug 27, 2011)

A sharp chain, proper rakers, and a working oiler will sometimes result in a bar and chain that is hotter than heck. That is OK as long as the B&C aren't hot like that all the time. I was cutting some cottonwood recently where the cut ends were kind of fuzzy and the B&C were WAY too hot to touch. Same a few days later when I was cutting down a bunch of small stumps. Same with semi-rotten logs that are big enough to take some time to cut.

The B&C gets hot. Nature of the business.


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## Jmaffei (Aug 27, 2011)

Glad to see I'm not the only one getting hot B+C's. I liked the post about proper chain tension, that will help I just think when you are turning so many rpms in hard wood there is going to be a lot of heat, the cutters arent lubed afterall. Maybe pine at 10 degrees Fahrenheit cuts cool; 30 inch diameter white oak in 80 or 90 deg temps is gonna build up some heat.


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