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View Full Version : Case Hardening Paste - Metal Working



Lionelgee
13th December 2022, 11:03 PM
Hello All,

Back in high school industrial arts - metalwork, some projects involved heating metal up to red hot and then dipping the ends of newly made tools into a tin of case-hardening compound. Just wondering what the stuff was and whether it is still available today?

Since the time era was the late 1970s the stuff is probably banned.

I want to harden the bevelled edges of a beehive knife that I use for separating sheetmetal after I have drilled out the spot welds. My next option is to copy the shape onto a section of old leaf spring.

The shape and thickness of the beehive knife is perfect for getting between layers of sheetmetal without distorting them too much. The only trouble is that I am using a tool for a purpose it was not actually designed for and the edges chip or slightly burr over. While a quick lick with a file does bring the bevel shape back, I am losing metal each time this maintenance work is done.

Kind regards
Lionel

p38arover
13th December 2022, 11:39 PM
I bought some of this years ago when I was building a Stuart-Turner model steam engine.

Cherry Red Case Hardening Powder
– E and J Winter - Bolton Scale Models (https://ejwinter.com.au/products/cherry-red-case-hardening-powder)

Lionelgee
14th December 2022, 12:20 AM
I bought some of this years ago when I was building a Stuart-Turner model steam engine.

Cherry Red Case Hardening Powder
– E and J Winter - Bolton Scale Models (https://ejwinter.com.au/products/cherry-red-case-hardening-powder)

Hello Ron,

Thank you for the link to the product. I just placed an order with them.

Kind regards
Lionel

POD
14th December 2022, 10:09 AM
I used that stuff to case harden a mild steel shaft many years ago, not worth the trouble. Have you tried heating and oil-quenching the existing tool? It may be made from a steel that will harden by simple means. If not, with such a simple form, you would probably be better off to reproduce it in a more suitable material as you say.

loanrangie
14th December 2022, 11:17 AM
In engineering at tech school we used the oil quenching method for a few of the tools we made, also case hardened the body of a socket wrench we made.

Tins
14th December 2022, 11:50 AM
Also good for splitting spot welds.. once you drill 'em.


https://youtu.be/MaCtNgXlcqY

Rick1970
23rd December 2022, 07:32 AM
I used that stuff to case harden a mild steel shaft many years ago, not worth the trouble. Have you tried heating and oil-quenching the existing tool? It may be made from a steel that will harden by simple means. If not, with such a simple form, you would probably be better off to reproduce it in a more suitable material as you say.

Used this method as well.
Milder steels seem easier to get a satisfactory result from, ie 1045 vs 4140.

Lot of old machinists swear very well used engine oil is the go over fresh stuff.... carbon content maybe?

rover-56
25th December 2022, 01:00 PM
Cyanide salts BE CAREFUL!!
Terry

BathurstTom
26th December 2022, 09:27 PM
I know a blacksmith/toolmaker who swears by Cotton seed oil. He swears by it. He taught at ANU for several years, so he is not a mug.