Rehardening frizzens - one size fits all? Musings for metallurgy masterminds....

It seems the answers to every how-do-I frizzen hardening question are universal, one size fits all - no one ever asks for more details: a frizzen is a frizzen is a frizzen. Heat the bugger up and quench it.

But at the same time, I often see discussion about the difference of materials/methods used by manufacturers and how that influences the quality/lifespan of the striking surface.

Meaning the same process is going to have slightly different results, at the molecular level. But to what degree? And does it matter?

If you had a bucket of frizzens that included samples from every manufacturer, DIY technique, use/abuse history, you-name-it, would you treat any of them differently?

...based on what you can (easily) observe?
surface area / thickness / gouging / total mass / pitting / ...

...based on its history?
manufacturer / age / (ab)use / past maintenance...

...based on all-knowing-infinite-cosmic-knowledge of every detail?
composition / heat capacity / crystal structure...


What's the worst that could happen if you didn't discriminate, and treated them all exactly the same?
Which ones are at risk of being on the losing side, if there is one? (Go on, name names!)



Or, put differently... if I could sell you a robot that hardened frizzens for you, what options would you want it to have?

"It seems the answers to every how-do-I frizzen hardening question are universal, one size fits all - no one ever asks for more details: a frizzen is a frizzen is a frizzen. Heat the bugger up and quench it."

If a frizzen used to spark and quits sparking, re-quenching it probably will not work, ever. The fact that it stopped sparking means it was probably case hardened, and use over time has worn the outer layer of steel away exposing low carbon steel or iron that will not spark. Heating the frizzen and quenching it will not add carbon back into the steel.

Original period flintlocks (those made before ~1880) were most always case hardened, iron or possibly low carbon steel. Generally the method used to get them to spark after the case was worn out was to braze a strip of high carbon steel to the face of the frizzen. This was done because it was a very fast fix, and often the face of the frizzen was wavy from wear.

A modern frizzen that happens to be made entirely from high carbon steel probably wouldn't really stop sparking, but rehardening it, if it were to lose its temper somehow would make it harder.

So your robot would need a spectrochemical analysis capability, and either the ability to re-case harden or braze old low carbon frizzens.

I don't know if this answered your question, but I hope it helped.

Mike

Mmcalc said:

I don't know if this answered your question, but I hope it helped.

Click to expand...

Not directly, but it still good information differentiating terms that are often casually thrown about as equivalent, plus it highlighted exactly how the sloppy abuse of terminology confuses intent! (Sad thing is, I had literally just hours before done a nod-and-smile "yeah, kinda, sorta, close enough...ish" in response to someone else's comment/explanation that equated heat-and-quench to case hardening. It somehow must have stuck in my head as a valid over-simplification...)

So, putting that lapse in cognitive function aside, back to the hypothetical bucket o' frizzens. Say I have the capability to case harden, braze, and a spectro analyzer to boot - heck, let's just say I've got all the toys and options at my fingertips - transformation, shock, chemical hardening, laser modification, the works.

What sort of differentiation might you make to determine how to approach each frizzen, and how much difference might it conceivably make vs. a one-method-suits-all approach?

Are there any generalizations one could make without the use of specialized identification equipment, based on characteristics like mfr, age, color, smell, taste....?

One method approach... Pack in charcoal hardening compound. Heat to 1625-1650F for around 3 hours or so. Maybe a little more. Allow to cool. Re-heat and to around 1525F and quench in a proper heat treating oil or even warm canola oil. Heat only the striking face with the torch when re-heating. Temper at around 350-375F. Further temper the pan cover up to the bend of the frizzen with a torch to a good blue color. This will draw the hardness of this area a little more. Grind the face and you're good to go.

I would use a different approach if I new the material. For example sometimes a brine quench can be best, but it can be more prone to cause cracking. We happen to use a brine quench to maximize frizzen hardness. Also, depending on geometry and material, tempering can be optional.

With this said, the one size fits all approach should work well with about any frizzen.

Jim Kibler
Metallurgical Engineer

Sorry , I'm not going to be any help but just like to tell you about my experience a few months ago . I got a lock and I needed to grind on the pan of the frizzen , even while being very careful , I , naturally , heated it and it would not spark anymore ...great . So its probably 1095 but I'm not 100% but tried to follow the instructions of two well know gun builders to reharden it .... Not good . I tried several times and was very fed up as now I'm wasting time and should have just bought a new frizzen to save time but I really want to learn how to regarded these frizzens in case it happens again ! Mad as a wet hen I think &%$@ it and I heat the frizzen to cherry red and quench it , face first , slow in water and no annealing ...sparked like a champ !! and still does and hasn't snapped , in half yet .... Knock on wood ..Go figure !! ... I certainly would think this is not the way to go about hardening a frizzen from L&R but .... all the other jumps through the hoop were useless . Who knows ...

One thing I tell people if you have to grind on a frizzen hold it in your fingers. You won't get it hot enough to take the temper out before you can't hold it anymore. Even then I frequently dip it in water to cool it. If you grind a modern frizzen this way and it won't spark it probably wasn't hard enough to start with. The exception was some of the older TC'S where to hard and flints that where pretty sharp wouldn't spark them very well. Then just draw them back at 400 degrees .

Rob M. said:

Sorry , I'm not going to be any help but just like to tell you about my experience a few months ago . I got a lock and I needed to grind on the pan of the frizzen , even while being very careful , I , naturally , heated it and it would not spark anymore ...great . So its probably 1095 but I'm not 100% but tried to follow the instructions of two well know gun builders to reharden it .... Not good . I tried several times and was very fed up as now I'm wasting time and should have just bought a new frizzen to save time but I really want to learn how to regarded these frizzens in case it happens again ! Mad as a wet hen I think &%$@ it and I heat the frizzen to cherry red and quench it , face first , slow in water and no annealing ...sparked like a champ !! and still does and hasn't snapped , in half yet .... Knock on wood ..Go figure !! ... I certainly would think this is not the way to go about hardening a frizzen from L&R but .... all the other jumps through the hoop were useless . Who knows ...

Click to expand...

I just went through the same thing with an L&R frizzen, it barely sparked when I bought it new a few months ago and I could only get 8-12 strikes from a new flint before the edge was blunted. I figured out that the flint was digging into the soft frizzen face and the edge was basically being ripped off like going across it with a file.

First harden by the usual instructions, not a single spark. Got ticked off and cherry red, rich flame until magnet wouldn't stick (same as before) but this time into cool water face first. The face crazed with spiderweb cracks. Heat-sunk the frizzen with a wet rag and slowly drew it back to a deep blue up to the bottom edge of the frizzen face, dropped it in oil tobstop the heat. Glass-hard face sparks ok now, not great but far betterbthan it came from L&R. I did purchase a replacement frizzen and will fit and harden/draw it when the other one breaks or quits sparking again. Drawing the temper at 375⁰F was not the solution for THAT frizzen.

Forgot to add, I cured all my frizzen problems permanently by doing one thing: Exclusively buying Kibler locks from now on. Got three of them and designing two more guns currently that fit each style he makes. When I think about it next time I will ask if he sells spare frizzens, I'm planning on living and shooting a lot for a long time yet and when I finally wear through the cases I want some drop-in spares.

Lightly touch the face of the frizzen to a grinder. Compare spark pattern to the spark patterns given by a file, piece of drill rod, rusty old butcher knife, and a common nail ( just examples; compare the spark pattern of frizzen face to very low, medium, high (old carbon steel knife), and very high carbon steels (file).

Now you’re roughly informed regarding the carbon content of the steel you’re dealing with.

As mentioned above, regardless of the steel, you can hardly go wrong with deep case hardening or adding a sole of hardened high carbon steel.

FWIW the famous Colonel Peter Hawker of early 19th century fame was in the habit of ordering his new flintlocks already soled with steel even from the best makers of the day.

It depends on the steel. A lot of cast frizzens are 6150 steel.

Pedersoli frizzens are case hardened EN42 carbon steel similar to 15N20 I think.

I first cake on some compound

I case harden both in a graphite crucible (with a lid) with peach pit charcoal at 1650 for 1 hour, i bring the temp down to 1350 for 30 min then I quench in a mixture of hot water and potassium nitrate, larger bucket.

Temper at 350 for 45 min, and temper the foot and pan cover at 600 until blue.

I mostly do this for new locks from casted parts.

l'Abeille said:

It seems the answers to every how-do-I frizzen hardening question are universal, one size fits all - no one ever asks for more details: a frizzen is a frizzen is a frizzen. Heat the bugger up and quench it.

But at the same time, I often see discussion about the difference of materials/methods used by manufacturers and how that influences the quality/lifespan of the striking surface.

Meaning the same process is going to have slightly different results, at the molecular level. But to what degree? And does it matter?

If you had a bucket of frizzens that included samples from every manufacturer, DIY technique, use/abuse history, you-name-it, would you treat any of them differently?

...based on what you can (easily) observe?
surface area / thickness / gouging / total mass / pitting / ...

...based on its history?
manufacturer / age / (ab)use / past maintenance...

...based on all-knowing-infinite-cosmic-knowledge of every detail?
composition / heat capacity / crystal structure...


What's the worst that could happen if you didn't discriminate, and treated them all exactly the same?
Which ones are at risk of being on the losing side, if there is one? (Go on, name names!)



Or, put differently... if I could sell you a robot that hardened frizzens for you, what options would you want it to have?

Click to expand...

I had read years ago about using leather as a carbon source to case harden a frizzen when in wilderness away from the blacksmith or gunsmith. This involved wrapping it in leather and then in clay to keep oxygen away.

We were camping when a flinter pistol of mine quit sparking well. I had a tin with a lid in my fire making kit for making char cloth tinder. Just for fun I cut a piece of leather off of something & wrapped the frizzen in it. Then put in the tin and in the fire pit. I covered it in hot coals and let it go for more than an hour, fanning the fire and coals to the highest heat while we sat consuming adult beverages. The next morning I found the leather completely charred and the frizzen sparked like new.

So if you are ever in a bind this costs nothing to try. This was 30-40 years ago so I don’t remember exactly how long we heated the can. Someone had dropped an empty bottle in the fire pit and it had actually melted so it was a hot fire.

I've hardened them before by grinding out the center portion where the flint will contact it, then I tig weld it in using music wire as filler rod. Then grind flush. It'll never wear again.

Music wire should be a great filler with TIG.

boberator said:

Music wire should be a great filler with TIG.

Click to expand...

It definitely is. It also hardens completely just from being heated and used as filler so there's no need to go back afterwards and harden the frizzen.

BeardedGunsmith said:

I've hardened them before by grinding out the center portion where the flint will contact it, then I tig weld it in using music wire as filler rod. Then grind flush. It'll never wear again.

Click to expand...

I was skeptical of this approach until I got an opportunity to try one. I had a frizzen for my Bess that wouldn't spark, so a friend faced like this. It sparked well, slightly higher rate of flint usage but no other problems. It lasted about 28,000 shots before the facing was worn through.

I have used Kasenit compound to case harden several frizzen's, that have lasted for hundreds of shots before needing re-hardening. Unfortunately Kasenit has been either discontinued or banned but Cherry Red works the same, but I haven't used it to harden a frizzen, so I don't have any history using it for that task.

FlinterNick said:

It depends on the steel. A lot of cast frizzens are 6150 steel.

Pedersoli frizzens are case hardened EN42 carbon steel similar to 15N20 I think.

I first cake on some compound

I case harden both in a graphite crucible (with a lid) with peach pit charcoal at 1650 for 1 hour, i bring the temp down to 1350 for 30 min then I quench in a mixture of hot water and potassium nitrate, larger bucket.

Temper at 350 for 45 min, and temper the foot and pan cover at 600 until blue.

I mostly do this for new locks from casted parts.

Click to expand...

1350 F is too low of a temperature to quench from. Little to no hardening will occur.

boberator said:

Music wire should be a great filler with TIG.

Click to expand...

Why not just re-sole or re-face with some 1095 steel ?

FlinterNick said:

Why not just re-sole or re-face with some 1095 steel ?

Click to expand...

Music wire is cheap. Ironically they sell tig wire that's specific for laying down a hardened surface and it's ridiculously expensive. I haven't tested the rockwell C of the music wire but it has to be at least 60 or so once tigged.