High Quality Chainsaw Bars Husqvarna Toys

HELP! MS440 crankshaft heat color

Stump Shot

Disciple of Monkey's
GoldMember
Local time
8:51 AM
User ID
1377
Joined
Jun 5, 2016
Messages
31,120
Reaction score
194,436
Location
Northwoods of Wisconsin
Country flag
Seen it on hundreds of older saws too.

Consider this Steve....if the connecting rod became so hot that it glowed cherry red (which is what it would take to change it's color), would the thin sheetmetal cage that is part of the rod bearing not melt?

The answer is yes. It would melt, and ooze out from between the crank and the rod. I've seen that too BTW.
Didn't care to extrapolate much on this as it was my day and had so much time to burn.
For starters, when steel glows red it leaves behind a black scale, think of a blacksmith here or new hot rolled metal when you get it.
Think of turning colors like if you cut too fast with a drill press or a lathe for example and get a colored chip coming off, nothing glowed red hot to achieve the steel to change color in this fashion.
Turning colors happens much before this, as a red glow starts at 1,000F up to 1,500F goes to orange at 1,600F to 1,900F and yellow 2,000F+.

Here's a color chart giving the degree level reached when observed.
main-qimg-12c59d06e847edab5182f4fc0f3f4fdc-lq.jpg

Here's a pic of my 660 that made 2 test cuts besides idle time and tune.
IMG_20230529_064738488.jpg

So with this little bit of knowledge it would/could quite possibly be plausible that the coloration on new saw rod ends was from the run time at the factory and not from manufacture, as it doesn't take a long time for friction to create heat and I would hazard to say that a tolerance mismatch of minute proportions could do this in short order.
It makes me wonder what the manufacture would say if a new saw with this "calamity" was put forth as a warranty claim what their response would be, this should tell the tale in short order one would think.
Personally I've only noticed this phenomena in used equipment as the number of new I get into is quite low in comparison no doubt.
But really the question is will it run? So far from what I've seen running and what my saw and others are returning to service, the answer for now would have to be a yes. Could there be long term ramifications? If so I would think that we would see the failures on a regular basis enough to come to a reasonable conclusion that it had, lacking them is much like how many licks are in a tootsie pop, either the answer is three or the world may never know.
We can now see the massive amount of heat created in your 880 example, which would have to be considered relatively unique as far as such a failure goes as how may get to see such a rarity, which had to be some sight to see indeed. Any pics by chance?
Alas, if it's just story time we're after, I once knew a gal that turned the color of every rod end she ever met, this however doesn't advance the subject matter at hand any more than automotive parts being made does though.
 

Mastermind

Chief Cat Herder
Staff member
GoldMember
Local time
8:51 AM
User ID
4
Joined
Dec 3, 2015
Messages
48,204
Reaction score
313,289
Location
Banner Springs Tennessee
Country flag
Didn't care to extrapolate much on this as it was my day and had so much time to burn.
For starters, when steel glows red it leaves behind a black scale, think of a blacksmith here or new hot rolled metal when you get it.
Think of turning colors like if you cut too fast with a drill press or a lathe for example and get a colored chip coming off, nothing glowed red hot to achieve the steel to change color in this fashion.
Turning colors happens much before this, as a red glow starts at 1,000F up to 1,500F goes to orange at 1,600F to 1,900F and yellow 2,000F+.

Here's a color chart giving the degree level reached when observed.
View attachment 379595

Here's a pic of my 660 that made 2 test cuts besides idle time and tune.
View attachment 379597

So with this little bit of knowledge it would/could quite possibly be plausible that the coloration on new saw rod ends was from the run time at the factory and not from manufacture, as it doesn't take a long time for friction to create heat and I would hazard to say that a tolerance mismatch of minute proportions could do this in short order.
It makes me wonder what the manufacture would say if a new saw with this "calamity" was put forth as a warranty claim what their response would be, this should tell the tale in short order one would think.
Personally I've only noticed this phenomena in used equipment as the number of new I get into is quite low in comparison no doubt.
But really the question is will it run? So far from what I've seen running and what my saw and others are returning to service, the answer for now would have to be a yes. Could there be long term ramifications? If so I would think that we would see the failures on a regular basis enough to come to a reasonable conclusion that it had, lacking them is much like how many licks are in a tootsie pop, either the answer is three or the world may never know.
We can now see the massive amount of heat created in your 880 example, which would have to be considered relatively unique as far as such a failure goes as how may get to see such a rarity, which had to be some sight to see indeed. Any pics by chance?
Alas, if it's just story time we're after, I once knew a gal that turned the color of every rod end she ever met, this however doesn't advance the subject matter at hand any more than automotive parts being made does though.
You're evidently deeply invested in your line of thinking on this subject.
 

Stump Shot

Disciple of Monkey's
GoldMember
Local time
8:51 AM
User ID
1377
Joined
Jun 5, 2016
Messages
31,120
Reaction score
194,436
Location
Northwoods of Wisconsin
Country flag
You're evidently deeply invested in your line of thinking on this subject.
That was just when I woke up this morning. I'm like oh yeah! There's this, that, the other... guess I just needed to sleep on it and rolled just the right way or some such thing to get the thought process flowing. Lol
Is a wonderment, it surely is.
 

Al Smith

Here For The Long Haul!
Local time
9:51 AM
User ID
537
Joined
Jan 14, 2016
Messages
6,143
Reaction score
13,564
Location
North western Ohio
Country flag
It's an interesting conversation .I might suggest "anvil fire " which is a blacksmithing forum .Lots of good info . There is a tad more to it than just heating up the metal .To make steel or iron harder it first has to have a certain amount of carbon in it .Mild steel you could heat and quince until the cows come home and it will never harden .The old time weapons makers plus blacksmiths used a soak heat in a charcoal bed to induce carbon
To prove a point to a friend who was a tool and die maker I made a lathe tool of mild steel and case harden the cutter using brown sugar -C6-H12-O6, another old trick almost nobody knows about .
 
Top