"Case hardening"

[garandman]

I got a nipple wrench / screwdriver tool that has a fairly soft / malleable driver tip.

Can it be hardened by heating (red hot) and then dunked in water / oil? Does oil work better?

Any ideas apprecaited. Thanx.

 

[necchi]

Yeah likely, but they kinda leave'm soft so they don't bugger-up the screw heads on the rifle,, :idunno:

 

[LRB]

Depends on what the steel is. If it is not high carbon, say at or above .4% carbon, it will not harden to any appreciable degree. If it is high carbon, you will need to temper after hardening or it will be brittle.

 

[garandman]

IIRC correctly (from the AK's I've built) the process is ...

1. Heat red hot.
2. Immediately dunk in water / oil.
3. Heat red hot
4. Let cool naturally.

Is that right?

 

[ohio ramrod]

If you heat it red hot the second time you will simply anneal the steel getting you right back to where you were before heating. To temper the steel after hardening you only heat it to 400 to 750 degees depending on the steel. A simple way to temper most steels is to heat them in a kitchen oven set at it's highest temperature for an hour let cool slowly, repeat two times. ( Be sure to do this whn SWMBO is not home ) :idunno:

 

[Bill Hall]

You could try one just to see how it does. Heat it cherry red, quench it, then test with a file to check if it hardened. If it did, anneal it back a little. If you like way it hardened, do the same thing with the other screwdrivers.

I bought some cheap screwdrivers on sale at Walmart one time, with thoughts of using them at work, since they tended to disappear or end up broken (I never took my good tools to work). I used one to make a scraper, heating and bending it, then heat treating it. To my surprise, it hardened up quite nicely. Not bad for 5 screwdrivers for about $4. Bill

I just re-read that you only have one tool, not a set of screwdrivers. Like I said, you could try to heat treat it, and if it doesn't harden, you still have what you started with.

 

[LRB]

What Ohio said. I would add quench in oil first. If no hardening happens, try water. Check with a file. If it does not harden in water, it's not going to happen.

 

[garandman]

Thanx for that explanation.

The tip of teh driver is so malleable right now, I actually did bugger a screw head with it. So I figger I got nothing to lose trying to harden this tool.

Far as doing this when the wife is elsewhere, I already done dried my Piettas in the oven....and she was fine with it. I gotts me a good woman.... :thumbsup:

 

[garandman]

Curious....why oil first? Why not go straight to water?

 

[mikemeteor]

this helps (me, anyway) understand the heat treating process a little better, including differential quench speeds.
http://tidewaterblacksmiths.net/2.html

 

[LRB]

The majority of steels will crack if quenched in water. Safer to try oil first when you don't know what steel you have. Canola oil will handle most. Warm it to about 130° to make it cool faster.

 

[crockett]

One warning- the oil can flash up so be sure you are in an area that a flash flame isn't a problem.
Check out Brownells- gun parts. You might be better off getting the right tool (screwdriver)
On a nipple wrench- I don't think it really needs to be hardened.
Case hardening on a soft- low carbob- follow the kasenit directions- red hot and quench- that's it.