CA-BC Annealing hardened steel

[Tomc938]

I have a friend that has access to hardened shafting. It is shafting from a mine site, so not sure what processes it has gone through.

Is it possible to anneal it in the oven so it can be machined easier?

Thanks!

 

[trlvn]

Toaster oven? No. Heat treat oven? Yes. The hardened parts need to get to about 1500 F and be held there for about 1 hour per inch of thickness and then cooled slowly.

If you can build a decent size bonfire, you can likely get the pieces hot enough. Let the fire burn out and cool in the ashes overnight and they should be annealed. Or maybe find a buddy with a forge?

Craig

 

[justin1]

Depending what application it was used it could only be surface hardened which is easy to figure out by cutting with a handsaw the depth of hardness will be shiny compared to the softer inner core. Then I guy knows how much to turn down to make it useable.

If it's a breaker tips for hydraulic rock hammer its probly hardened thought out and would probly contain lots of internal stresses some which may not come out easy after a single round of a annealing. That and not sure how machinable magnesium based steel is.

Also if your buddy gives you a crusher ball that's been used I would avoid welding or try cutting it as they are known to explode from internal stresses.

 

[Tomc938]

Thanks Justin!

I was talking to my neighbour (who is also a Justin) said they are pins from machinery joints. I'm guessing any hardness would be significant.

 

[justin1]

There probly just a 4140 pre hardened. Usually you want pins to wear out before bushings. I would still throw one in handsaw and find out if they are hardened at all. They probly will turn pretty good as is.

Edit.
With carbide maybe not hss lol

 

[Tomc938]

There probly just a 4140 pre hardened. Usually you want pins to wear out before bushings. I would still throw one in handsaw and find out if they are hardened at all. They probly will turn pretty good as is.

Edit.
With carbide maybe not hss lol

Thanks! I’ll give it a whirl.

 

[buckbrush]

I was duplicating pins for a Japanese mini excavator. The original pins seemed to be case hardened on the outside like Thompson shafting, hardness files would not make a scratch on them.