Author Topic: Lock welded (Read 6816 times)

billd · « **on:** March 22, 2015, 06:32:30 PM »

I'm working on a repair of an original lock. The part you hook your thumb on to cock it was broken off and missing. I bought a new similar shaped hammer and cut that part off. I took it to a local welding shop thinking I could get the new piece TIG welded to the old lock.

It turns out the original hammer is cast iron and the new hammer is cast steel. The welder TIG'ed it but had to use silicon bronze rod because of the dissimilar metals. Anyone know what will darken the weld seam?

Thanks,
Bill

jerrywh · « **Reply #1 on:** March 22, 2015, 06:50:18 PM »

If I had that job I would make a new hammer. I am not sure if it will work but Rio Grande has an oxidizer for Brass that will turn brass black I will look and see what it is composed of. I have all that stuff in the shop. Even if you oxidize it the bronze will not stay that way for ever.

Clark Badgett · « **Reply #2 on:** March 22, 2015, 06:50:59 PM »

While I certainly would rule the possibility out, are you sure that lock is original? Never heard of originals using cast iron.

billd · « **Reply #3 on:** March 22, 2015, 08:46:53 PM »

Jerry, I agree a new hammer would have been the way to go, there wasn't enough money it the job to do it.

Clark, I am 100% positive the lock is original. The break looked like cast iron to me. I spent 42 years of my life in a machine shop. The welder is a full time all his life welder. As soon as he hit it with a rod he said it was cast.

Bill

JTR · « **Reply #4 on:** March 22, 2015, 08:56:57 PM »

Instead of tiging it, he should have welded it with cast iron rod. But to do that now, you'd have to remove every bit of the bronze.

Maybe brown the hammer and boil it black, then blacken the bronze with brass black.... But to make that look right, you'd probably have to blacken the lock plate too..

Filing out a new hammer is the best solution, or finding a modern replacement that you can file to shape.

Good luck, John

Stophel · « **Reply #5 on:** March 22, 2015, 09:08:06 PM »

I don't know about the cast iron thing, but, brass brazing is how it would have been repaired 200 years ago.

Acer Saccharum · « **Reply #6 on:** March 22, 2015, 09:40:01 PM »

Lots of stuff was made of cast iron; it was the plastic of the 19th century. It doesn't mean it was good, but it was cheaper than hand wrought.

halfstock · « **Reply #7 on:** March 22, 2015, 09:43:40 PM »

Your right Stophel but even then it would not have lasted. Even then a gun smith or blacksmith would have replaced the hammer with a more durable metal.

Stophel · « **Reply #8 on:** March 22, 2015, 09:54:40 PM »

Braze is plenty solid (assuming it's done well), especially for something nearly stress-free like the little "comb of the cock".

This lock was converted to per-cussed by making a cap-busting-thingy and clamping it into the jaws of the flint cock. Then it was all brass brazed together, the top of the screw cut off and the sides of the jaws cut down and flattened to sort-of resemble a percussion hammer. It's still together.

I'd come up with a new hammer, myself, BUT, I don't think your little thumb piece is gonna fall off.

jerrywh · « **Reply #9 on:** March 22, 2015, 10:10:00 PM »

I have two type. One is called liver of sulfur and the other is bronze and copper oxidizer. They are sold by Rio Grande jewelry supply. I would give you some but shipping is prohibited. Google liver of sulfur. You might be able to buy some at a pharmacy. According to the website Walmart has it.
About 8 years ago I was asked to weld some on an African trade musket that had a hole in the pan. That would not tig weld and it was cast iron also.

shortbarrel · « **Reply #10 on:** March 23, 2015, 12:21:05 AM »

I have brazed cast iron and welded it too. both make strong joints if done right. Both were done with a gas torch. Birchwood Casey makes a brass black or they did.

JCKelly · « **Reply #11 on:** March 23, 2015, 04:57:12 AM »

There is Cast Iron and there is Cast Iron. And there is also Cast Iron

The metal used for Gramma's iron skillets, and good modern Lodge cast cook ware is Gray Iron. Gray iron is brittle, great for pans & old engine blocks but would not survive long at all as a cock or a hammer on a lock.

Another type of cast iron is Malleable Iron, been used for about two centuries or more now. General Motors' Central Foundry used to make & anneal great quantities of Malleable Iron automotive parts.

In the 19th century malleable iron was used for things like musket nose caps and pepperbox frames. Among "real" revolvers only Remington and that French pinfire used malleable iron frames. the Gov't objected to Remington's malleable iron frames but there is no record they did anything about it. I have owned one .36 cal Navy conversion that was obviously cast, and seen others. Oh, yes, and the "steel" triggerguards &c used on London Colts were malleable iron.

Personally I would not use it for a hammer, but it is cheap. Dixie used to sell malleable iron cocks, both percussion & flint

The last type of iron is called White Cast Iron, because when broken the fracture is all bright and crystalline looking. This stuff is so hard it is a problem to even grind it. Normally it is cast, then annealed to turn it into malleable iron.

Randall Steffy · « **Reply #12 on:** March 23, 2015, 05:54:20 AM »

In addition to grey iron and malleable iron there is ductile, or nodular iron. Similar to malleable iron but stronger and more flexible, ductile iron gets an inoculation of magnesium during the melt which causes the nodular condition of the graphite as opposed to the graphite flakes in brittle gray iron. Ductile iron can be bent without the annealing required of malleable iron, both having a significant degree of plasticity.

JTR · « **Reply #13 on:** March 23, 2015, 05:56:41 PM »

Is it a percussion, or flint hammer/cock?
John

Mark Elliott · « **Reply #14 on:** March 23, 2015, 11:25:39 PM »

It is amazing all the stuff you can learn on this site.

WadePatton · « **Reply #15 on:** March 24, 2015, 12:05:16 AM »

Quote from: Mark Elliott on March 23, 2015, 11:25:39 PM

It is amazing all the stuff you can learn on this site.

I'm glad the metallurgists came to the table. Well done brethren.

shortbarrel · « **Reply #16 on:** March 24, 2015, 12:56:05 AM »

How old is the lock ??. Have rebuilt a lock that had a cast iron lock plate and a wrought iron cap lock hammer and internals. Bet the plate was frying pan cast iron. It welded just fine with an acetylene torch and forty year old filler rod. The lock was broken in half at the tumbler hole. Never put it on a rifle, but will some day.

billd · « **Reply #17 on:** March 24, 2015, 01:06:55 AM »

It's a percussion lock, about 1850 Massachusetts gun.

I goggled liver of sulfur and found you can do the same thing with hard boiled eggs. I'm going to try it. If it doesn't work it will look like an original repair.

Thanks again,
Bill

Clark Badgett · « **Reply #18 on:** March 24, 2015, 03:29:39 AM »

I know all about the malleable iron. Used for a lot of things, but I have never seen an original hammer from gray iron. Possible, but I've never seen one, and the brittle nature of gray iron might be the reason they aren't common.

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Author Topic: Lock welded (Read 6816 times)

billd

billd

billd