The Home Machinist!

I tried the Case Hardening experiment over the weekend, and it was a dismal failure... The images and text are in the "Projects & Plans" section off the main page...

Any suggestions are welcome...

Frank
http://www.theworkshop.ca

Frank,
Everything looks pretty good, but I found no mention of you having quenched the pieces. Did I overlook that part? If your black material was carbon, and if you achieved the necessary heat, your items had no choice but to absorb carbon. Without quenching while at red heat, however, the parts would end up dead soft, especially if you left them in the box to cool. A very important part of the process was to remove the parts while still red hot and quench them.

Regards the one part appearing to be softer than the control piece-----yep! If you didn't quench the stuff, what you did was to anneal the material completely, so it would have ended up somewhat softer than it began, especially if it had any degree of heat treat to begin with. Cold working alone will generally harden materials to some degree, so even low carbon material will generally be a little softer from having been heated and slowly cooled.

Harold

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Wise people talk because they have something to say. Fools talk because they have to say something.

Harold you're right, I just let it cool, That was the critical step I missed...

Thank-you, and also to any body that emailed me privately that I missed... This is truely the beauty of the internet, I like to think of it as collaberative intellegence... the cumulative experience of numerous individuals focused on specific issues or problems.

Frank
http://www.theworkshop.ca

Frank,
That's the best news yet! All you have to do now is get them red and quench them. Don't keep them at heat for very long or they'll scale and decarburize to some degree. Let us hear how it turns out........

Harold

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Wise people talk because they have something to say. Fools talk because they have to say something.

Frank, as Harold says, you need to quench to harden.

I have had very good results using a compound called Kasenit - obviously contains a lot of carbon, but also some 'magic ingredient' to speed up the absorbsion. With Kasenit you can get a 5 thou case by a single 'heat to bright, dip in the compound, dip in water' The compound flows over the surface when hot enough, and a deeper case can be achieved by keeping the object hot with a torch, and multiple dipping in compound before the quench.

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Andrew Mawson
Battle, East Sussex, UK