Does a fly need to be hardened?

[Jim Curlee]

The sear bar broke on my rifle. I know what does that have to do with my fly ?. lol

I sent the "manufacturer" pics next to a 6" rule, and ordered a new sear from "the company" out east.
NO it was not a Chambers lock.
They sent the wrong sear, but suggested I send the lock back, and they would get me the correct sear.
Well after $90, my rifle still won't fire.
I can get the lock to fire if I push pretty hard on the sear bar, but the trigger will not fire the lock.
After a bit of studying I see that the sear catch's in the half-cock position.
They filed their homemade fly too much, which allows the sear to fall back into the half-cock position.
By the way there was nuthin wrong with my fly, worked just fine when I had the lock.
Then they charged me for a new fly, and did not return my original, but they did return the broken sear, and the first sear they sent which did not work, and I have no use for.
They also called me to tell me that the lock sparked just great, SURE.
Okay I'll quit. LOL

I'm just really disappointed that a reputable manufacturer would do this to anybody.
Now they won't answer me at all!

So, I made a new fly.
My question is: do I have to harden the fly?
If so, what is the best way to go about doing that?
Thanks
Jim

[smart dog]

Hi,
Absolutely.  Hardened and then tempered to the same temp as the sear and tumbler, probably about 580-600 degrees.

dave

[Jim Curlee]

I'm guessing since I could cut the fly with a file, that they left out that important process. LOL

What color are you heating the metal too?
Guessin I won't have to fire up the torch, thinkin a propane torch might do the trick?
Thanks again
Jim

[Bob Roller]

The locks I made all had a fly made from 0-1 "tool steel",hardend,polished and tempered
to a light straw color.No problems reported in the 50+years.Same with the sear,same material.
The tumblers are 1144 "stressproof" which is an unusual material in that it machines like leaded
steels and hardens like 0-1 or drill rod and I used the same tempering method on it as well and
again,all seem to me OK after decades of use.
Is the lock you have trouble with an American made one or an import from "Hoonosewhair"?
Bob Roller
PS, An ordinary Bernz-O-Matic torch will work.

[smart dog]

Hi,
Bob's recommendation likely is very good.  I tend to temper the tumbler, sear, bridle, and fly at a bit higher temp. At 580-600 the color would be deep blue. I think the key is to make sure they are all the same hardness and temper so one does not wear on the other.

dave

[Jim Curlee]

I am not a machinist/gunsmith, I'm a putz with a shop. LOL
Would a guy quench the part after the heat-treat?
If you do would you use water or oil?
Jim

[Clark Badgett]

I am not a machinist/gunsmith, I'm a putz with a shop. LOL
Would a guy quench the part after the heat-treat?
If you do would you use water or oil?
Jim

I am a machinist and I do a fair amount of heat treating at work. Whether or not you quench after hardening depends on the steel used. Stuff like A, D, O and W prefixed steels automatically tell you what to quench with, A=air, O=oil, W=water and D is supposed to mean it can get any quench, but we always just air quench it. Don't forget to draw back your part after the hardening part. For that you will need to find out what temp to use. 500-600 is fairly universal for many steels but some do differ so be sure.

[Jim Curlee]

Clark:
Your saying I heat it once, cool it, then heat again?
Jim

[Clark Badgett]

Clark:
Your saying I heat it once, cool it, then heat again?
Jim

Heat it to the hardening temp, which is usually in glowing red state, quench it in an appropriate fashion. Clean the metal to bright then heat it to the 500-600 degree range and then let it cool naturally on it's own.

[Tim]

Clark:
Your saying I heat it once, cool it, then heat again?
Jim

Heat it to the hardening temp, which is usually in glowing red state, quench it in an appropriate fashion. Clean the metal to bright then heat it to the 500-600 degree range and then let it cool naturally on it's own.

May I ask if top jaw screws and cock screws can be hardened in this same manner?
I am new to flintlock rifles and hardening steel parts is an interesting subject.

[Mauser06]

As for your last question,


Depends.  They may or may not be hardenable steel.  Mild steel won't harden unless it's case hardened which is a different process all together. I'd assume mild steel is cheaper and easier to work with and it's usually what is used where hardness and temper isn't needed.  Chances are you aren't going to be able to harden those parts...

[Nordnecker]

Here's what you should do. Do a test on the same piece of stock you made the fly out of. Heat the piece until it's orange and quench in water. Put it in a vise and see if a decent file will cut it. This should tell you whether it will harden or not.
If it hardened there is hope. If it didn't then you need better stock.
There's a lot to learn on hardening steel. It can be very simple or very complex, depending on many variables.
But you have to start with hardenable material.  Mild steel isn't hardenable by quenching .