H-13

[John Martin]

Today I got in six pieces of 1/2" round H-13 steel for making some punches and one cold chisel. If I follow the directions in The Complete Modern Blacksmith, the steel won't crack, and it will harden and temper correctly?

And one more question. I want to do stock removal for precision on these. Should I use my angle grinder? Or Bench Grinder?

[Pault17]

Hey M. nice score,
I would suggest grinder, bench mount type.
are the bars annealed (i am hoping)?

[John Martin]

Well I finished my tong rivet punch, and my cold chisel. Will harden and temper tomorrow. Can't get any pictures as my camera is broken and doesn't want to work.

Saving the other four for when I need them.

Edited August 20, 2008 by m_brothers

[metalliferous]

If it's the Complete Modern Blacksmith by Weygers, then no, I don't think it provides an appropriate guide for heat treating H13. Alloy steels, especially hot work ones like H13, require sometimes much different treatment. Here's what I got from azom.com regarding h13 heat treatment:

Air Hardening Hot Work Steels of H13 Type

These steels may be air hardened in sections up to 60mm. Above this thickness, whilst full hardening will occur, carbide precipitation at grain boundaries wilt lead to poor tool life and low impact strength.

Heat Treatment

The preferred procedure is to quench into a fluidised bed furnace or salt bath held just above the Ms point. This allows the cooling rate to miss the critical areas of the

[blksmth]

m_brothers, Weyers book does not give information for H13 as was previously mentioned. I know several smiths that just forge H13 and then air cool. That is all they do. If you want the tool a little harder you can temper at approx. 1050 degrees F, but for smith work it is generally not necessary. H13 should not be water cooled when in use, but then I know you can often get by with dunking it in water quickly to cool if necessary. You are taking a chance of cracking the tool, though as it is not a water quench steel and water is too fast of a quench for H13. Blacksmiths like Tom Clark and Uri Hofi make more than one hot use tool (typically chisels and punches) of the same size out of H13. One or 2 of the tools can be air cooling while 1 is in use. H13 typically does not get hard enough for cold work unless professionally heat treated. See a temperature chart for heat treating several steels common to blacksmiths at: http://www.blksmth.com/heat_treat_guide.htm Hope this helps,

[Quenchcrack]

Please note that H13 is made to do hot work. It is lower in carbon than most tool steels and is not nearly as prone to cracking as D2, for example. To get the material to the point where it will form a crack due to water quenching, your tool must be RED HOT! If you are using punches and slitters as they are intended, they should not show any color in use. Cool them BEFORE they get hot enough to re-form austenite that might crack if you water quench it. Use punch lube so you can pull the punch out of the hole quickly to preven overheating. Make only one or two hits on your slitter and then dip it into water to cool it. Keeping the tools cool will maintain the temper, too.

[John Martin]

So once I put it in the fire, I should just take it out, and let it air harden, and then be done with it, and just use it for hot work.


So.... I put the punch in the fire, let it get to dull cherry, then take out and let it air harden and cool down over night?

[mcraigl]

That's what I do. After final forging, I reheat to cherry'ish, then set aside (on a piece of kaol wool insulation so the whole tool cools evenly) and let cool til cool to the touch. I understand that the tool would be slightly harder if tempered, so will probably try that some day too, but tempering at around 1000 is hard to judge without a tempstick which I don't have and I've been forbiden from putting "any more of that dirty metal stuff" in my wife's computer controlled kiln. Of course, what she don't know won't hurt me right??? Anyway, I made a 1/8 x 7/8 slot punch from 3/4round H-13 and heat treated as I suggested and have punch a pile of holes with it and it still looks like brand new. I also made a 1/4" round tapered punch from the same material and it too looks like new. I grinded/sanded/buffed the working end of both of these tools to a very high polish, then treated them with punch lube as Quenchcrack suggested and they both work very, very well. Good luck.

Edited August 21, 2008 by mcraigl
clarity

[John Martin]

I didn't do anything with them, other than grind them, they both tempered themselves today, I punched a ton of holes today for practice with the punch. The chisel, works fine.

[LDW]

These fullers and the chisel were all made from H-13. In this class we were told not to quench the steel and after forging, the H-13 would reach a rockwell hardness of 54C. We were told to make two chisels as well so one could cool when it got hot.

[John Martin]

Pictures of the two punches and one hot chisel. HeHe.

1/4 Punch and 1/8 inch Punch 1/2" Chisel.

[psilogen]

looking good - it's hard to tell from the picture, but, if you haven't, be sure to dress the punches with a file or grinder. if you've got sharp edges around the flat punching end, it will better cut out a plug of metal instead of just spreading it out like a drift

and I haven't set mine up yet, so I can't be sure, but I think you'll want much heavier chain around the anvil to dampen the ring