Hardening Mild Steel - Anyone know any tricks

[Ronk]

Hey all.

I am working on a template to make 1911 grips. It is a 5/16" steel piece that I can attach the grip blanks to and run them over my belt sander to shape them. I think it will help save some time while sanding them and marking the grip bushing holes. I forgot that mild steel doesn't harden easily/at all with the small amount of carbon in it. I was hoping that someone had any ideas that I might be able to use to keep the belt sander from eating away at the template when I'm sanding. Trying to keep from redoing the template again in high carbon steel.

I will produce the other couple of templates I plan on making in high carbon steel and will have to get them hardened. Just incase I am missing something, I assume that if a file won't scratch properly hardener steel, sandpaper won't be to big of a problem. Am I correct in this?

One last question, can anyone recommend someone to harden these for me?

Thanks for any input or help!
-Cory

 

[mike miller]

google "super quench" I think it is water saturated with salt and Dawn dish soap added.

 

[Shadowrider]

Well you could carburize it. This puts carbon into the surface for a shallow depth and it can be made very hard. It's also known as case hardening. But seeing that your sanding belts use aluminum oxide abrasive it still won't work. Diamond has a moh's hardnes of 10.0, alox is 9.0. No steel is going to hold up, you just aren't going to get the steel as hard as the abrasive no matter how you heat treat it.

 

[Rod Snell]

I assume that if a file won't scratch properly hardener steel, sandpaper won't be to big of a problem. Am I correct in this?

It's been a long time since ferrous materials class, but I believe grinding and using carborundum paper is the way to shape hardened steel. Case in point, final grinding and sanding of custom knives after heat treatment.
Suspect your metal template will abrade significantly

 

[264killer]

a different direction ! may be u could clamp ur template to a milling machine , fine adjustment down to clear template by .001 or what ever.

 

[dennishoddy]

Why not just buy some 4140, or tool steel, and be done with it.

You can buy oil quench or air quench in the tool steel.

If you get oil quench, its really easy to harden and then temper.

Oil quench tool steel, is magnetic, but at proper quench temperature, it will loose its ability to be magnetic.

Suspend it over a vessel of quench oil on a magnet, heat it until it looses its magnetism, and it will drop into the quench oil.(google quench oil)

The material will be in excess of 60 Rockwell when it cools.

Hold it with some vice grips, and use a cutting torch with a heating tip, and brush it back and forth across the material.

When it turns a light brown patina, it will Rockwell around a 45. The darker the patina, the softer the metal will be.

I was shown this in 1980 by a machinist that was 85 years old. He learned it as a young man.

You asked for some tricks of the trade. you just got a good one.

 

[Ronk]

Well you could carburize it. This puts carbon into the surface for a shallow depth and it can be made very hard. It's also known as case hardening. But seeing that your sanding belts use aluminum oxide abrasive it still won't work. Diamond has a moh's hardnes of 10.0, alox is 9.0. No steel is going to hold up, you just aren't going to get the steel as hard as the abrasive no matter how you heat treat it.

I had thought about carburizing it, but thought I wasn't going to be able to get the surface hard enough. Thanks for the info on the Moh hardness, I hadn't thought to search that out. Looks like through more searching, getting a Rockwell hardness of 60, only gets around a 7.5 on Moh's scale.

It's been a long time since ferrous materials class, but I believe grinding and using carborundum paper is the way to shape hardened steel. Case in point, final grinding and sanding of custom knives after heat treatment.
Suspect your metal template will abrade significantly

I was thinking along those lines, but wanted to be sure before I put too much more effort into it. Thanks!

a different direction ! may be u could clamp ur template to a milling machine , fine adjustment down to clear template by .001 or what ever.

I wish I had a milling machine. My drill press and sliding vise just doesn't work well enough.

@dennisshoddy...thank you for that info. That is a fantastic trick of the trade to learn! I don't know what I like to dabble with more, wood or steel.