[TheForge] Re: [TheForge] Re: [TheForge] Heat Treating 5160 w
as Welding 5160
David E. Smucker
[email protected]
Sat Aug 30 14:24:00 2003
Could be Grant, But I have watch a number of smiths make quick and dirty
tooling out of coil springs -- 5160 most likely -- and have them crack
following heat treat -- with no normalize. They always blame the "old
spring -- most like had a crack to start with". I have had this happen only
once and I was cutting corners, no normalize and a water quench. I've
even seen a demo with new 5160 -- making a punch and it cracked, again
didn't take the time to do a least one normalize. They did temper using
retained heat in the rest of the part.
Now some of these folks were fast -- made some good money resharping jack
hammer bits -- they only took one heat to reshape the bit, let it cool to
the black -- which in effect gives them the normalize and a smaller grain
size -- and then reheat to critical, quench and draw back (temper) using
retained heat and the file test and a final quench. With 100 jack hammer
bits to resharpen time is money.
All I trying to say is there is a balance in what we do.
Dave Smucker
----- Original Message -----
From: "gblacksmith" <[email protected]>
To: <[email protected]>
Sent: Saturday, August 30, 2003 1:31 PM
Subject: [TheForge] Re: [TheForge] Heat Treating 5160 was Welding 5160
> Dave: Maybe the reason they don't need to temper is because they not
> reached full hardness. Grant
> ----- Original Message -----
> From: "David E. Smucker" <[email protected]>
> To: <[email protected]>
> Sent: Friday, August 29, 2003 2:24 PM
> Subject: [TheForge] Heat Treating 5160 was Welding 5160
>
>
> > Yep, Chuck -- I don't think you would suggest cryogenic quenching for a
> > blacksmith's hot punch -- but I wouldn't think of not requiring it on
the
> > purchase of a $ 10,000 five percent chrome cold mill work roll made from
> ESR
> > steel.
> >
> > It didn't get talk about much in this series but your earlier point of
the
> > need to normalize to refine grain structure is one of the more important
> > things that is easy to do and many times skipped by the blacksmith heat
> > treating his tools. In general there are only two things we can do to
> > reduce grain size -- forging, and normalizing. We do a lot of
increasing
> > grain size by multi heats at high temperature and really should
normalize
> > before heat treating. Jim Batson suggest doing this three times for
knife
> > blades -- I would settle for once for most tools, but many times it is
> just
> > skipped. Are we really in that big of a hurry.
> >
> > The other one I don't understand is the great desire to NOT TEMPER -- it
> can
> > be done quickly and safely for almost any tool. Why leave it out. At
the
> > very least put it in the oven at 350 *F for an hour. It gives only a
> small
> > reduction in hardness and a big increase in toughness. (And yes it may
> well
> > get tempered in service from use on hot metal, but the time to temper is
> > right now, following heat treat. As you have said many blades have been
> > lost by the failure to temper now, saying I do it tomorrow -- but it is
> > cracked in the morning.)
> >
> > Dave Smucker
> >
> > ----- Original Message -----
> > From: "Chuck Robinson" <[email protected]>
> > To: <[email protected]>
> > Sent: Friday, August 29, 2003 3:41 PM
> > Subject: [TheForge] Re: [TheForge] Re: [TheForge] Heat Treating 5160 was
> > Welding 5160
> >
> >
> > > Right Dave,
> > > And we haven't even begun to discuss:interrupted quenching,
> mar-quenching,
> > > banite quenching, multiple quenching, differential quenching, clay
> > > quenching, and cryogenic quenching.
> > > Chuck
> > >
> > >
> > > _______________________________________________
> > > http://mailman.qth.net/mailman/listinfo/theforge
> > > theforge mail list group photo site is
> > > http://www.photoaccess.com
> > > Login: [email protected]
> > > password: anvil
> > > ___________
> > >
> > >
> > >
> > _______________________________________________
> > http://mailman.qth.net/mailman/listinfo/theforge
> > theforge mail list group photo site is
> > http://www.photoaccess.com
> > Login: [email protected]
> > password: anvil
> > ___________
> >
> >
> >
>
>
> _______________________________________________
> http://mailman.qth.net/mailman/listinfo/theforge
> theforge mail list group photo site is
> http://www.photoaccess.com
> Login: [email protected]
> password: anvil
> ___________
>
>
>