[TheForge] Superquench/hardening power hammer dies

Wed Dec 29 18:03:21 EST 2004

Bruce,  The issue I have with the name "Superquench" is that I have run into 
many metal workers / blacksmiths that think superquench does something magic 
to turn mild steel into tool steel.  This is one of the greatest items of BS 
out there.  As a strong technical person you understand that we are not 
changing the physics or chemistry of the steel by using superquench -- but 
there seem to be many folks that think this is the case.  A36 hardened in 
superquench is not tool steel.  It is just A36 about as damn hard as you can 
get it.  Does it make a good cold chisel or a good wood working tool - NO it 
doesn't.  It can get to maybe Rc 50 and those tools should be at least Rc 58 
to 60 or a little harder.  For tools, dies etc. use the right steel.  There 
are lots of "junk" steels that are close to the right steel, it doesn't have 
to be the perfect steel -- but good is a far  better than A36.

I recently had the luck to come across some 7/8 dia. 4340 at a local scrap 
yard.  When I found out I could harden this unknown steel -- I went back a 
bought all that was left -- about 40 -- 12 foot sticks.  Later I was able to 
get it tested and found it to be 4340 -- I am one happy camper with a lot 
steel for tools in my private stock.

Dave Smucker

----- Original Message ----- 
From: "Bruce Freeman" <FREEMAB at pt.fdah.com>
To: <theforge at mailman.qth.net>
Sent: Wednesday, December 29, 2004 4:10 PM
Subject: Re: [TheForge] Superquench/hardening power hammer dies

> Isn't this the whole point of using superquench?  Take mild steel and
> bring it up to the hardness of unhardened tool steel (or better)?  Mild
> steel is easier to work, generally cheaper (though scrounging makes any
> steel pretty cheap), etc.  If those aren't sufficient advantages, then
> use the tool steel and be done with it.
>
> Superquench is cheap and easy to make.  The Basic I is not hard to get.
> Try it.  You'll like it.  If there's a question whether it will work on
> a large die, try it on a block of mild steel of the appropriate weight,
> testing hardness before and after.  (Machineries Handbook probably
> describes methods...)  If it hardens sufficiently, go ahead and make the
> die.  If not, you're not out much.
>
> BTW, I prefer the name "superquench" so as NOT to confuse the issue.
> That's what it's been called from the get-go.  Note that it's not called
> "super-hard quench" or "magic quench" or whatever.  "Super" is just
> Latin for
> "over , above; besides, beyond, moreover; remaining, over and above".
> (http://www.archives.nd.edu/cgi-bin/lookup.pl?stem=super&ending=)
> Superquench provides an action not available in most other quench media,
> aside from those made with lye.  Or so Robb Gunter tells us.
>
> Bruce
> NJ
>
>>>> osan at netlabs.net 12/29/2004 2:08:09 PM >>>
>
>
> PlumDon at aol.com wrote:
>> The recent superquench discussion has prompted a question: do we
> really  need
>> to heat treat our power hammer dies?
>
> I certainly don't think open dies need to be heat treated,
> assuming
> they are made of a suitable tool steel that will be tough enough for
> the
> job of mushing hot metal, but it can be beneficial.  The heat treat
> doesn't have to bring up a high hardness.  4140 is only at something
> like C37 at its highest measured toughness.  This isn't very hard, but
>
> at its peak, 4140 is a very tough steel.
>
> Closed dies, on the other hand, are much more likely to require
> some
> heat treatement in order to ensure reasonable life, especially where
> any
> thinner sections and sharp corners may exist.
>
> > I have some of 4140  and 5160 and do
>> not think they have been hardened and tempered.
>
> But they are nevertheless a world tougher than A36.
>
>> I grind them  back to shape
>> about every six months on my 2x72 Grizzly. Not a REAL heavy user  but
> they do see
>> some action. I wonder if heat treating out weighs the gain from
> not.
>
> A proper heat treat, while not essential is still beneficial
> IMO.  It
> leaves the steel in a far better condition than if it is left in an
> annealed state.
>>
>> I got the impression from a couple of the posts that many of the
> power
>> hammer dies are not hardened.
>
> Many are not, from what I've seen.
>
> I've had the same discussion regarding hot tooling.  Some folks
> are of
> the opinion that a punch need not be heat treated because it is being
> driven into hot steel.  I can accept this as valid, especially fro
> plain
> tool steels, but I do believe that doing a proper heat treat will leave
>
> the tool in better condition for its intended duties as opposed to
> leaving it in its from-the-mill anneal.  This is especially true of hot
>
> work alloys susch as S7 and H13, as well as high speed steels like M2.
>
> M2 in a fully annealed state, while far tougher than mild steels, is
> still very soft compared to the hardened state.  I have machined
> annealed M2 with hard M2 bits on the lathe with no trouble.  I would
> not
> use M2 for top tooling without heat treat if I didn't have to.
> _______________________________________________
> Manage membership or unsubscribe at:
> http://mailman.qth.net/mailman/listinfo/theforge
> theforge mail list group photo site is
> http://www.photoaccess.com
> Login:  blacksmithblacksmith at hotmail.com
> password:  anvil
> ___________
>
>
> _______________________________________________
> Manage membership or unsubscribe at:
> http://mailman.qth.net/mailman/listinfo/theforge
> theforge mail list group photo site is
> http://www.photoaccess.com
> Login:  blacksmithblacksmith at hotmail.com
> password:  anvil
> ___________
>
>
> 