frizzen not hardening?

[Hemo]

Another question for the metallurgical experts here.

I'm assembling Jim Kibler's Dolep lock parts. I'm at the point of hardening prior to tempering. Jim's instructions called for hardening everything (except the plate and cock) to 1525 degrees F, then oil quenching.
I didn't precisely measure the temperature for heating, but rather heated all the springs, sear, tumbler, and frizzen to bright orange all over, using a MAPP gas torch inside a small enclosed brick chamber, then quenched immdiately in vegetable oil. Everything except the frizzen appeared to be nicely hardened.  A file glides like glass over everything but the frizzen without cutting metal. I can still make cuts in the frizzen surface with a file, however. I repeated the process, heating the frizzen to a glowing orange all over, immediately oil quenching. I can still score it with a file.

I suspect the steel used in the frizzen may be different that that in the springs, sear, and tumbler. Or maybe I'm not heating long enough to fully penetrate this bulky part. Would a brine quench work better?

I do have some of that "Cherry Red" powder, similar to Kasenit, that I could apply and at least get some surface hardening.

I also have an oven I can slowly heat the frizzen to 1525 degrees and hold for a long period of time at that temperature prior to quenching. Should I go that route?

Any suggestions welcome!

Gregg

[ericxvi]

The only time I tried using MAPP gas to harden something [I think it was a spring], I got similar results, would not harden. I've used a coal forge from then on with no problems.

[SingleMalt]

I don't know the size of the frizzen in question, but for Siler-sized frizzens and larger, I use two MAPP torches with Kasenite.  I've never had to re harden one that wouldn't "take" the first time.

[Jim Kibler]

Gregg,

If you send the frizzen to me, I would be happy to do my best to harden it for you.

Send me an email and we can work out the details.

Thanks,
Jim

[P.W.Berkuta]

Since it is  Jim Kibler's kit why don't you ask him and get the correct answer and stop wasting your time guessing or asking others???

[Jim Kibler]

I just thought I should add a bit...  I hardened two the other day.   I heated the same as you describe and quenched in water with about 1/8" - 1/4" of automatic transmission fluid floating on the surface.  I tempered at about 350 - 375 F and they seemed to work pretty well.  

Jim

[Hemo]

I just thought I should add a bit...  I hardened two the other day.   I heated the same as you describe and quenched in water with about 1/8" - 1/4" of automatic transmission fluid floating on the surface.  I tempered at about 350 - 375 F and they seemed to work pretty well.  

Jim

Thanks, Jim,

I just ran the frizzen in my oven at 1525F for a good hour to make sure heat was fully penetrated, then did a quench in brine (basically tapwater with table salt added) and about 1/4 inch of light motor oil floating on the top. (I didn't have any ATF handy). It appears to be harder, and may work out okay. I'll let you know if not!

What is the ATF supposed to do?

BTW, I see the Dolep locks are no longer on your store website. Are they all gone, or are there any spare parts available in the event of disaster?

Gregg

[M. E. Pering]

Gregg,

Jim should know, but if it were me, I would heat it to the point where all magnetism was lost from the frizzen, then immediately quench it.  I use used synthetic motor oil myself, but that is just me.  I think the carbon in the used oil contributes to the hardness.  I do use a product from Brownell's  that is basically Kasenit or Cherry Red equivalent, which does a decent job.  But I don't use an oven, just the magnet test, and it seems to work well enough for hardening any steels which I have tried to harden in the past. 

Matt

[jerrywh]

I can't say what type of steel the foundry used to cast Jim's frizzens. At times in the past I have had frizzens that were cast out of 6150. 6150 makes pretty good springs and at times in the past one of the foundries used it to cast frizzens. It will not harden as hard as hard as 1075 to 01 straight carbon steel because it only has .5 carbon content. As a result when I got one of those I case hardened them.  The first one I got like that I kept on trying to harden it at a higher temp. until it finally cracked.

[smart dog]

Hi Gregg,
Hopefully, you have it sufficiently hard.  Just make sure to temper it well using your new oven.  Program the controller to come up to the final temperature very slowly maybe no faster than 150-200 degrees/hr so it does not overshoot the target temperature.  Also Gregg, you may eventually get set up to case harden parts in your oven.  At that point, I suggest you reharden the frizzen by case hardening it despite the fact that it made of steel that can be through hardened.  During the hardening process you used, some carbon in the steel on the surface may get burned off as you bring the temperature up to 1575.  If you case harden the frizzen, you will add carbon back to the surface.  I always find that my case hardened frizzens perform better than those heated through, while exposed to air, and quenched. 

dave

[Hemo]

Thanks for all your replies! I tried striking a flint on the face of the frizzen today, and it dented the surface without sparking, so obviously it's not hard enough. I'm going to go with case hardening.

Gregg

[Joe S]

You could braze or rivet a new face on the frizzen too.  That's a historically correct repair, and it's not hard to do.  Lasts a lot longer than case hardening.  I had to do that on my current gun.   

[Jim Kibler]

Gregg,

Glad to hear you had success.  The frizzens were cast from 1095.  I recarburized these to compensate for any decarb in the castings.  Keep in mind you could get some decarb from the long furnace hold time prior to quench.  I just use a torch with a carburizing flame to heat.  It would be a good idea to belt sand the surface back a bit to remove any potential surface decarburization.

Jim

[Hemo]

A follow up-

I belt sanded the striking surface of the frizzen and polished it pretty smooth. I found a can of "Cherry Red" case hardening compound in my sundry supplies (apparently equivalent to Kasenit). I treated the frizzen face three times, heating the upright and pan cover portions of the frizzen to bright orange and dipping the face surface into the hardening compound, leaving a crusty heap of gray crumbly material on the surface.  I then reheated the frizzen and crusty stuff to orange, and immediately quenched in cold water, per directions. I didn't try to harden the toe or screw hole. After three rounds of this, a file skated pretty smoothly over the frizzen face, and striking it with a flint did produce some sparks and no gouges. I'm presently tempering to 375F in my oven. With any luck this may do the trick. If not, I can case harden it further.

Fingers crossed,

Gregg

[jerrywh]

 Refering to what Jim said about sanding the surface, I never use to believe that would help but tried it one time and it solved the problem completely.

[Stan]

Hemo, the longer you keep any 1000 steel at critical temp the more carbon is lost, one hour is way too much.
Your frizzen should be hot packed for a few hours & then hardened & tempered. 1095 steel is WATER hardening steel & will never get truly hard in oil, people use oil because it is safer. However using water is the correct method. So how to harden in water?  For 1095 frizzens & other 1095 small parts, use a container that will hold two quarts of water, heat the water to 100 degrees m/l & add about 1/3 cup of salt, heat the frizzen to critical temp & quench moving the part rapidly in the water, temper at 375 degrees.
Note, I hold the frizzen face up when heating with a torch & have the face lightly coated with
Kasenite.
Best regards Stan Hollenbaugh

[Dphariss]

I would not quench in water.... Especially if you have a lot of work in the part. Like an engraved frizzen. One broken part is enough.....

Quench in WARMED light oil like ATF maybe with about 25% Marvel Mystery oil. In a gallon I heat a 4x4 chunk or 1" steel to near red and put it in a gallon of the oil to warm it. Yes warn oil does a better quench.  Cold oil does not conform to the part as well as warm oil and does not cool the part as fast.....

Dan

[Bob Roller]

I would not quench in water.... Especially if you have a lot of work in the part. Like an engraved frizzen. One broken part is enough.....

Quench in WARMED light oil like ATF maybe with about 25% Marvel Mystery oil. In a gallon I heat a 4x4 chunk or 1" steel to near red and put it in a gallon of the oil to warm it. Yes warn oil does a better quench.  Cold oil does not conform to the part as well as warm oil and does not cool the part as fast.....

Dan

I used warmed oil when hardening the frizzens on a run of flintlocks for a shop in Germany years ago and it
worked fine.The frizzens were cast from 52-100 in a foundry in Tennessee and so far,no problems reported
about those locks.

Bob Roller

[Stan]

Just a note ! I have hardened hundreds of frizzenns as well as small internal parts & never had one break.

[Hemo]

Final (I hope) update:

After three applications of Cherry Red powder to  the face of the frizzen, quenched in cool water, final tempering of the frizzen to 375F, spring hardening and tempering and semi-final assembly, I'm happy to say the little lock now sparks like a champ! It does need a firm sustained pressure on the sear, or else it catches on the half cock notch, as others have posted (no fly).

I have little more polishing and engraving to do, and it will be done. Pics to follow.

I have meticulously photographed the process of assembly of this lock, starting from Jim Kibler's cast parts, the first time I have I have atttempted this, and was very much flying by the seat of my pants. Some other people on this site have asked if I could post a tutorial on assembly of this lock, which I would be happy to do, including all my errors and fixes, if people are interested. I could do an abbreviated overview or a really detailed synopsis, whatever people would like!

Gregg

[James Rogers]

Give us both barrels Greg! I have a long way to go on mine.

[Curtis]

Gregg,  I would be very interested in seeing what you have to post!  Including the trials and tribulations!

Curtis