tempering ?

[MLMartin]

ok ive tempered a hand full of chisels and fullers and knives, all of them i would anneal in sand, then harden in oil, then heat up again and run the colors until i got the color i wanted and then quench in oil, well i am now making a anvil tool for my treadle hammer, 1" by 4" by 6" block with a hardy shank attached, to drop in the tool post, what im wondering is how to temper it, i annealed it in my forge for a few hours to real the stress it had for welding on the shank, then i hardened it in water, some kinda of low tool steel not quight sure what but some carbon, it hardened alright, a file would only cut into it a little bit, well with how large it is i was going to do the last temper by putting it into the oven at about 540 for a hour or two, i will monater the temp with a good thermometer, my question is sence i will not be bringing the already hardened tool above 540 is there any reason to quench it when its sat at that temp for a long time, sould i just let it cool down in the oven, or do i still need to quench it?

[pete46]

The Longer It Stays Hot The More Hardness Is Lost.
I Would Quench As Soon As It Comes From The Oven.
Then Season To Taste!:rolleyes:

[JohnW]

I don't feel qualified to answer your question, but no, you don't need to quench when tempering in an oven. If you were tempering a piece by another heat source, like a torch or your forge, by applying high heat to one side, it would be necessary to quech it to keep from running past the desired color on the tool side.

[Ferrous Beuler]

Tempering is one of those things that is not easily self taught by reading a book, etc. It is best to learn while standing at the elbow of someone experienced. Pay attention then when it's your turn have them critique your work (abuse it) then show you what you did wrong. :)Dan.

[Daryl]

The tempering process for an anvil would be far more straightforward than hardening. While I haven't hardened and tempered an anvil, I have done so on a flatter (same principle, much smaller scale). I had read a book on it and tried it myself (successful after four tris) - the process involved has to ensure that the edges would not end up harder than the center (difference is in the larger mass in the center not bing able to cool off at the same rate as the edges (the rate of cooling from non-magnetic temperature to cold - hardening); this is done using a water hose or stream aimed at the center and allowing the water (or whatever you are using as a cooling agent) to flow equally over the surface. Hardening can be verified using a file.

Remember, it took many tries to get a decent harden and temper on a two and a half inch square flatter; I doubt an anvil should be a first project.

As far as I know, the best person to contact would be John Adolph - unless you can go visit the Refflinghaus factory.

[Hillbillysmith]

Daryl, I think he is talking about an anvil tool. Not a whole anvil.

Mlmartin15, yes, you would quench this in your choice of water or oil. Otherwise, just letting it cool will anneal it as you have already done, which would be pointless.

Because you welded it, you annealed it to relieve the stress you have put on it, this is good. You then hardened it until a file barely cuts it. And now, you want to temper it. (Correct me if I'm wrong).

Depending on how brittle the piece is already, you may not need to temper it. Tempering is for steels/alloys that, when hardened, are too brittle to sustain themselves in taking abuse cause they will crack and/or break. Just to be safe, I would temper it though because of being used in a treadle hammer, but the best advise I have is: try it with another piece of the same thing (if you have any more) and do the same process over making another piece, weld/anneal/harden to where you are now with your current piece. And (without tempering) beat that thing to death and see if it breaks. If not, then put it in the treadle hammer and pound the living daylights out of it. And THEN if it doesn't break, there should be no reason to temper the tool. And in doing so, you now have TWO tools. I have made things that I have only hardened and not tempered and they work just dandy, but it ALL depends on the steel.

Hope this helps.
-Hillbillysmith

[mike-hr]

If you put the piece in the oven at a set temp,( I would try for more like 450F instead of 540), it won't lose more hardness the longer you leave it in.. What I was taught, is an hour for inch of cross section, at the thickest part. Turn off the oven at the end of the time, and go to sleep. To lose more hardness, increase the Temp, same amount of time, an hour for inch of cross section. More time won't affect it.