make a mainspring

[Battis]

I have an antique Bacon .31 cap and ball revolver that needs a new mainspring.
I have a diagram and photo of what it should look like. I have some Colt repro springs to make it from. I've read and researched and asked about how to heat treat and form the spring, but it's not settling in my brain as to the best method.
Is it easier than I think?
1st pic - what it should look like
2nd pic - diagram (listed as a Manhattan mainspring but it's the exact same). There's also a small square connecting plate that I can make from a washer.
http://i105.photobucket.com/albums/m217/pohill/DSCN3086.jpg
http://i105.photobucket.com/albums/m217/pohill/IMG.jpg
http://i105.photobucket.com/albums/m217/pohill/DSCF3494.jpg
Last pic is where it's going. There's a non-working spring in there now.
http://i105.photobucket.com/albums/m217/pohill/DSCF3507_zps2ffe8a57.jpg

[mooman76]

If you can't find someone here to help you, you could try to go over to muzzleloadingforum.com There are guys there that make their own main springs and know about exactly what needs to be done step by step . I don't think it's really that hard if you have the ability and things you need to make it but it's also up to the individual and how talented they are in doing this.

[junkpile]

It's actually not very complicated. Start by annealing or normalizing the spring stock. I would prefer annealed, but normalized may be acceptable, you'll know if you have to fully anneal it as soon as you hit it with a file.

Shape it and form it to your heart's content. Once complete, just heat treat it, and then temper it. If you skip tempering, it's going to end up breaking on you. Heat treating alone doesn't leave a consistent structure throughout the steel, I would guess that martensite forms on the surface even if it's oil quenched, but I can't say that for sure.

Also, be sure you get everything polished up very well before heat treating and tempering, and re-polish after. Any little scratches or nicks will become stress risers when you put the spring into use. I can look up the colors for treating and tempering for you if I can find my book.

I don't have a tremendous amount of experience with this. I only know the basics. I'll second the suggestion to hit up the muzzleloadingforum. The Gun Builder's Bench has a tremendous amount of knowledge available. You'll have to register to see that forum. You'll find some amazing work there.

[Battis]

I will check out the muzzleloading forum. Thanks for the info.

[Boerrancher]

In the gun shop I worked at in college the owner would make a spring, and heat treat it, then temper it using his Lyman lead furnace. I don't remember what temp he would heat the lead to, but when it reached that temp he would submerse the spring in the molten lead and keep it there until he was positive it had reached the temp of the lead. He would then remove it and let it air cool, and re polish it. It would then be installed. I saw him make just about every type of spring for a gun you can think of and never a one came back needing reworked. I just don't remember the temp he heated the lead to.

Best wishes,

Joe

[Mk42gunner]

What is wrong with the spring that is in it now? Maybe you could re-heat treat and temper it so it will work. If not at least you have something to go by while making the new one.

Robert

[Fly]

Temper can be around 425degrees for one hour.I temper my knives in a toaster oven.I have done
a lot of heat treat before I retired from tool & die.But I,m not a spring maker even thow
I have made some simple springs in the past.The advise on a good polishing is very important.

So with the advise above it worth a try.If it brakes you out nothing but your time.

Fly

[Battis]

So...I should anneal the spring (I anneal my 50-70 brass in the lead melting pot), then heat it and shape it, then temper it.
I could try and bring the spring that's there back to life but it's not in the correct shape.

[Fly]

Tell you what.I have some 1095 high carbon steel I can make that thing from.If you pm me
I will give it a try for free.I,m pretty sure I can make it in my machine shop shop.If it don,t work, your out nothing.PM me & we can see what I can do.

Fly (can't stand a ole pistol like that not being used,wink)

[Junior1942]

Fly, you da man!

[Fly]

Fly, you da man!

Heck Junior I,m retired, but not dead yet.Hey we love these ole guns &
it won,t take much to make that thing.If it can get him going great.

Fly

[junkpile]

If you anneal it, you won't need to heat it to form it for the most part. You might need to for tight little curls and things, but you should be able to work it cold.

Once formed, then heat treat and temper.

[Battis]

That's where I get messed up - terminology. What is the difference between heat treat and temper?

[Fly]

Heat treat is bringing it up to temp & holding it there for what ever time for the alloy you are harding.Temper
is after it has been hardened & cooled you bring it up to a much lower temp & whole it there to remove stress.
Temper will take some of the hardness out, but very little if done right.Don't confuse temper & annealing.Aneal
is to bring it down to a soft state.

Hope this helped Fly

[junkpile]

I'll do some digging and see if I can find my book. The lock kit I bought from Jim Chambers had a lot of information, too. I checked his website, but don't see it on there.

[junkpile]

I located it, but it didn't have the needed information. It had an article on trigger springs for flint rifles. Much thinner and shorter than you're doing. He had recommended bringing the steel to blue, and letting it air cool. With that thicker stock, You're probably going to need to heat and quench, and then treat it in the oven, or chase the temper with a torch.

All of the formulas and ideas can change depending on your steel, but they should be relatively static. Make sure you have reasonably good spring steel to start with, or you're doomed to failure.

Just get some spring stock that's roughly the thickness you're after, and start experimenting. All it's going to cost you is a little time and a lot of enjoyment. And if you're not successful, you've found something that doesn't work. Have fun.

[Fly]

junkpile does he say what alloy steel in the info?That can make a big difference
on the temps & type of cooling, ect.
Fly

[junkpile]

I can't remember right off. Will have to try to remember to look when I get home. It may be the spring from a lawnmower rewind, but I just can't remember. Doesn't talk about tempering. That stuff is so thin, I'm sure it cools off fast enough to harden up good.

Also, Track of the Wolf used to carry the Kit Ravenshear book on making springs. I don't have it, but have heard that it's a good resource. I think it was around $5.

Battis, are those springs that you're using cast? The Dixon book might have some information on springs. I can't find mine right now. We just moved and I'm still trying to find some stuff.

[junkpile]

Here's a quick guide:

http://www.mlagb.com/blackpowder/201001_springs.pdf

[Fly]

That's good info, bud.Like I said before I'm no spring maker, but I did do a lot
for heat treating in making dies, & so on.All high carbon alloys are different.
Take A-2 tool steel is a 1800 degree steel for 2 hours & air cooled.4140
is a 1400 heat treat steel & oil quenched, & so on.Thats why I asked.

Fly

[junkpile]

Yeah, I know where you're coming from.

I deal with steels on an endless basis. I like it because there's always new stuff to learn, so many variables that come into play. Good to exchange ideas on all this stuff. Fun to experiment, too.

Right now I'm messing around with joint restraint, composition parameter, and hydrogen control for some stuff we're doing at work. Had some problems with it before, and don't want it to happen again. Always something new.

[Fly]

Well your over my head on that stuff for sure.I,m just a wore out ole tool & die maker.

Fly

[Battis]

I got a copy of the Kit Ravenshear book a year or so ago. I read it then put it down to let it all soak in but it didn't. I bought the Colt mainsprings from Dixie Gunworks. The guide you posted looks good and should help.

[junkpile]

Fly, if you're an old tool & die guy, I'd learn way more from you than you ever could for me. I suppose you live down in the United States, though?

Battis, what is Kit's book like? What did you think of it?

[Battis]

I'll have to pull it out and read it again. As I remember, it was mostly about making V shaped mainsprings. It was informative but kinda advanced for what I was looking for.
Now where did I put it...