Using Heat for Automotive Work

[mtbtim]

Your not getting it anywhere near hot enough to temper, anneal, normalize, Or harden it. Just think about how much heat goes into the steel when they weld it. The only reason I don’t like to heat things is because it tends to burn the paint off. You might in extreme cases put enough heat into it to case harden a very small part of it.

https://youtu.be/KFdFsfSAuyc

This is a fantastic trick, I have used it a bunch of times. On mufflers, a friend bet me $20 I could not get his 20 year old rusted exhaust bolts off. With this trick they came right off. It’s seriously like magic.

I need to try that trick out.

 

[Mark_BC]

I think I took a metallurgy course once and from what I remember you have to heat it way up until it's pretty much red hot to change the crystalline structure of it which is what will affect strength. If you do get it that hot then it may make it weaker, but not more brittle. It would bend easier which means it would probably be less likely to catastrophically break. That's assuming the metal was hardened to begin with which I think would be unlikely.

 

[thegipper]

I need to try that trick out.

Ditto

 

[I_bRAD]

https://youtu.be/KFdFsfSAuyc

This is a fantastic trick, I have used it a bunch of times. On mufflers, a friend bet me $20 I could not get his 20 year old rusted exhaust bolts off. With this trick they came right off. It’s seriously like magic.

Have done this before a few times and I wouldn't say it's magic but definitely a tool in the box. Last time I did this I still had to use oxy-propane and a lot of it to get the nut off.

And to the original post- that was quite a bit of heating on the axle of an ATV, and that quad has seen plenty of use since with no issue.

 

[thezentree]

Your not getting it anywhere near hot enough to temper, anneal, normalize, Or harden it. Just think about how much heat goes into the steel when they weld it. The only reason I don’t like to heat things is because it tends to burn the paint off. You might in extreme cases put enough heat into it to case harden a very small part of it.

This.

https://youtu.be/KFdFsfSAuyc

This is a fantastic trick, I have used it a bunch of times. On mufflers, a friend bet me $20 I could not get his 20 year old rusted exhaust bolts off. With this trick they came right off. It’s seriously like magic.

That's the wackiest shit I ever did see. I've got to change TREs on my 200k mile GMC this afternoon, I'm going to give that a try.