Dull chains...does it really kill saws....how?

[Mattyo]

Disagree. Look at the chips. A sharp chain will cut through the wood fibers; a dull chain will try to tear them, in addition to the friction created by rubbing past the wood with the rounded edges. I think that someone may have already suggested trying this with a kitchen knife to see how much force it takes you to cut through a piece of meat with a sharp and dull knife.

Philbert

No question using a dull instrument requires more effort overall to cut through something, and perhaps you won't cut anything at all if dull enough.

BUT, overall effort and load are 2 different things. The more load is placed on a motor, the more the RPMS drop. ...and vice versa... the more the rpms drop, the more the assumed load. Therefore, a sharp chain cutting through wood will load a saw more than a dull chain doing zero cutting but adding heat to the whole system...




with regards to that 254, yes it got hot.... the question is why

 

[Philbert]

Therefore, a sharp chain cutting through wood will load a saw more than a dull chain doing zero cutting but adding heat to the whole system...

Sorry. Can't follow your logic. A dull chain does not skate across the wood with zero cutting. It grabs, it tears, it lugs the saw, and bogs it down, causing the clutch to slip, etc.

Philbert

 

[Wolverine]

Philbert, that chain pic i posted imo would be very very hard to load the saw. I think you'd have a very difficult time getting revs to drop, which of course would heat up bar/chain/rim/clutch/bearing etc. The top plate became a sort of ramp. And this type of damage isn't hard to replicate. Arborists hit metal a lot and I'm sure they don't immediately stop to sharpen. So I get where Matt is going in thought.

 

[cus_deluxe]

So the guy in the video i posted is my neighbor. I know him well. Hes the type that goes and buys a new chain when his current chain doesnt cut. Hed be totally baffled if i talked about top plate angle or depth gauges, or chain pitch....i can almost guarantee that chain has never been sharpened.

 

[Philbert]

Philbert, that chain pic i posted imo would be very very hard to load the saw.

I was responding in general terms - that chain is a 'special gem'. 'Sharpness', IMO is a continuum, not a binary value ('sharp', 'not sharp'). So lots of guys continue to cut, drag, tear, etc., which I believe is harder on the saw.

Philbert

 

[Al Smith]

Milling is just plain hard on every thing .The only worse is a giant stump .

 

[Philbert]

So the guy in the video i posted is my neighbor. . . . Hes the type that goes and buys a new chain when his current chain doesnt cut.

(What does he do with his old chains?)

Philbert

 

[cus_deluxe]

To me it proves that you can sufficiently load a saw to stall the clutch just by having a very dull cutter, with proper depth guage setup, regardless of how blunt/rounded that cutter is.

 

[cus_deluxe]

(What does he do with his old chains?)

Philbert

Probably tosses them haha

 

[Dub11]

So is this the best chain ever?

 

[Wolverine]

Not sure I can convey my thoughts to words here, how does the motor know the difference? Kinda like putting a saw on a dyno with a motorcycle brake. Heat produced by the bar to chain friction I get... totally. But in loading the motor, I don't.

 

[t4driller]

This is just a thought and question.... when cutting with a dull chain and the bar gets screaming hot, does the bar heat up enough to pinch the rails shut on the bar causing more drag on the chain / motor?? Acting as more "load".

 

[danimal]

THERE CAN ONLY BE ONE!

Watch it buster...that is my firetruckn line...
Ask Randy, we chatted, thats me finish line..

 

[danimal]

Milling is just plain hard on every thing .The only worse is a giant stump .

I just luv fresh,giant stumps..
Burns like coal.

 

[Mattyo]

Not sure I can convey my thoughts to words here, how does the motor know the difference? Kinda like putting a saw on a dyno with a motorcycle brake. Heat produced by the bar to chain friction I get... totally. But in loading the motor, I don't.

Exactly my point. Load is load, and it bogs a motor. sharp chains then and therefore are good load? a dull chain with a low raker is bad load?

a dull chain that doesn't cut hardly at all (dusty instead of chips) cannot load a motor .. so then and therefore the extra stress either comes in the form of heat soak from the bar, or extra heat in the motor from (effictively) piss revving it through the whole "cut" which took way longer than otherwise and was at higher rpm (generates more heat) than the airflow through the motor is designed for?

 

[Homelite410]

 

[Stihlkillstrees]

Turn the oiler all the way off on a saw and run it. I bet after a while it won't run.

 

[huskihl]

Exactly my point. Load is load, and it bogs a motor. sharp chains then and therefore are good load? a dull chain with a low raker is bad load?

a dull chain that doesn't cut hardly at all (dusty instead of chips) cannot load a motor .. so then and therefore the extra stress either comes in the form of heat soak from the bar, or extra heat in the motor from (effictively) piss revving it through the whole "cut" which took way longer than otherwise and was at higher rpm (generates more heat) than the airflow through the motor is designed for?

The added load is from dogging in and pulling up on the handle to get it to cut, which results in added bar/chain friction. The resulting added heat makes its way from the bar to the saw.
A sharp chain loads a saw way more than a dull one. It's the dogging in to get it to cut that creates the added heat

 

[Mattyo]

Turn the oiler all the way off on a saw and run it. I bet after a while it won't run.

i agree.... but why?

 

[Mattyo]

A sharp chain loads a saw way more than a dull one. t

i agree, hence my posed question in the first place