Color case hardening in the old days....

[knifemaker3]

Anyone have any historically correct ways of how they color case hardened steels before electricity came into play?

I'm thinking it must have been done in the forge or maybe a fire pit?

Curious as I'd like to try it on some underhammer builds I have planned for this fall.

Thanks.

[Mark Elliott]

It would have to be done in a forge to bring it up to the proper temp.    You could charcoal blue over an open fire, but not caseharden.   

[John Archer]

Mark,
Taylor Sapergia has successfully color casehardened in an open fire. I wouldn't have thought to do it that way either.

http://americanlongrifles.org/forum/index.php?topic=29351.50

John.

[Mark Elliott]

John,

I read the thread you referenced.   It seems to me that Taylor was doing a color case finish, not actual case hardening.  To case harden,  you must impart carbon into a thin layer of iron/steel in order to create hardenable steel in that layer; heat that layer above the recrystallization point (generally 1500-1600 degrees F); and then quench in water or brine.     There was no mention of quenching, and the photo definitely did not show the crucible red or orange, which it would have to be in order for the contents to be at the proper temperature.    He may have done this, but I see no evidence of that in the thread.   I find it difficult to believe you could get an object in the fire to 1500 degrees or better with a plain open wood fire as shown.   There would have to be some air introduced into the fire to get the temp up.  If Taylor really did get to recrystalization temp with an unaided open wood fire,   then hopefully, he will chime in on this.

 

[knifemaker3]

I agree I don't think just an open fire pit would work.  but a closed one with air introduced like an earthen forge would or I better say should.  Of course a regular forge would also work.

I've always heard the temp to get color case hardening was 1400-1450.  Then hold for a set amount of time.  At least that's what I've always read on it?

I was just curious if anyone had any actual information on how it was done back in the day.  I always assumed they did it in a forge but have never read anything of actual info on how it was done.

[David Rase]

You should really define "open fire" before you answer this question.   Others may disagree, but I consider a forge to be an open fire.  I have no doubt that you can case harden over an open coal fire.  I have melted brass in a graphite crucible in my forge several times.  Brass melts approximately 400 degrees hotter than you color case harden at.
David

[John Archer]

Interesting thread. Enough to prompt me to do a little browsing for info. To pack harden, a temperature of 1425F must be reached and held for over 2 hours. Get the crucible hotter and it takes less time. Queries about camp fire temperatures gave responses all over the map, but temperatures hot enough to melt glass (beer bottles) were easily obtained. Glass apparently melts at 1600F or so. It has a lot to do with the size of the fire and the fuel used.

Time for Taylor or Jerry to chime in.

John.

[WadePatton]

two words:  hollow log


 

[WadePatton]

Or any sort of vertical chimney can be used to create a hotter fire. 

[Calaloo]

I color casehardened an action using a case made of black iron pipe with one end welded up and the other end capped with a slip top. I kept it hot for over an hour using several bags of charcoal briquettes in a kind of stacked fire brick "oven". I quenched in cold water and got colors that were grey, blue and some subdued reds but nothing to brag about.

To color only 1100* will work but little or no hardening will result. To study color casehardening you can visit the Marlin Owners forum and read the thread about the subject.

I see no reason that the old timers could not have done it the way I did and with a little experimentation they could have gotten good results,
Bill

[JPK]

      knifemake 3, Maybe this thread will help you.
http://americanlongrifles.org/forum/index.php?topic=30187.msg289003#msg289003

[Dphariss]

I color casehardened an action using a case made of black iron pipe with one end welded up and the other end capped with a slip top. I kept it hot for over an hour using several bags of charcoal briquettes in a kind of stacked fire brick "oven". I quenched in cold water and got colors that were grey, blue and some subdued reds but nothing to brag about.

To color only 1100* will work but little or no hardening will result. To study color casehardening you can visit the Marlin Owners forum and read the thread about the subject.

I see no reason that the old timers could not have done it the way I did and with a little experimentation they could have gotten good results,
Bill

The old timers had forges so I can't see them doing this.

Dan

[jerrywh]

 They had furnaces for thousands of years.  Coal or charcoal or wood whatever burns. You don't need a forced draft just a draft.
 I did my first case hardening in a wood stove with a frizzen packed in a baby food can.

[bob in the woods]

I use my wood stove, good hard wood fire and parts i.e. frizzen, packed in a tuna can. Seems to work.

[Curt Lyles]

 I remember Ken Netting talked about Edson Meyers Makin knives,gun locks,ect using mild steel and case hardening in his forge all the time.Maybe Mark Herman can chime in here cause im sure Mark knew him also.I would have liked to work with him ,sharp guy at the fire . Curt

[jerrywh]

 




I have case hardened parts in a wood fire several times when I was young.  Any kind of fire tha twill get ap too 1500° and stay there for an hour or more can be used for case hardening. I used to put my canister in the ashes and build the fire on top. As the fire burned I just added more wood. A forge will work if it is big enough but be careful   not to use too much draft because it will over heat.  A good big wood fire works well.

[smokinbuck]

HI Curt,
Didn't see this until now, regarding Eddy Meyers. Luckily I did know Eddy and was privileged to have been at his shop. Eddy did do case hardening in his forge of locks, knife blades and other items but like so many of the things he did he just knew how. It was like  a cook being asked about ingredients in a favorite recipe, add a little of this and a little of that. He did a fine job and rarely missed and he didn't hesitate to try to explain to us that were uneducated, but that is as far as it got for me. I knew my limits and went to the master when I needed help, still do.
Mark