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Posted By: David Furman welding a hole in barrels - 02/25/11 07:28 PM
there's a thread in swap and trade here:
barrels with holes linky

I knownothing at all about metal, barrels or welding, I'm just curious about this from an academic standpoint. Is this a legitimate fix for a set of barrels, not so much from a cost perspective (i.e. maybe not for this set, but maybe on a set of tubes with a higher value) but from a strength perspective? I'm curious if anyone has done this and if anyone has thoughts on it.
Posted By: Ithaca5E Re: welding a hole in barrels - 02/25/11 08:21 PM
I saw a Perazzi for sale once that had ports welded closed. You could not see the welds inside and had to look damned hard to see anything on the outside. There's not too much stress near the muzzle and welds closer to the breech might be a different story. Anyway, the owner was honest about it and offering the gun at about 75% of what an untouched gun would have been
Posted By: doubletrouble Re: welding a hole in barrels - 02/26/11 04:38 AM
I have had 2 small splits welded near the barrel ends, one on a Parker the other on a Smith. Both were done by Freddie Bruner in Escondido, Ca. Done well. I shot Dove this season with the Parker and had not one problem. The Smith I have not used yet.
Posted By: bill schodlatz Re: welding a hole in barrels - 02/26/11 02:53 PM
I saw Oscar weld a damascus split near the muzzle. After refinishing it was almost invisable. bill
Posted By: Chuck H Re: welding a hole in barrels - 02/26/11 03:20 PM
I have welded a set of sleeve barrels into the original breach assembly.

Posted By: Run With The Fox Re: welding a hole in barrels - 02/26/11 04:45 PM
Just one word of caution here lads- HAZ (heat affected zone) input could cause solder to break loose-and welding heat causes stresses, so a mandrel or chill bar might be needed to prevent and "out of round" condition on a barrel- FYI-
Posted By: eightbore Re: welding a hole in barrels - 02/26/11 11:02 PM
Run, I'm sure that all "hot" work will be completed before the relaying of the ribs.
Posted By: Chuck H Re: welding a hole in barrels - 02/27/11 01:01 PM
Along the lines of "chill bar" and such; when welding a barrel, it will cool quickly due to the cooler surrounding barrel. This can cause what is sometimes referred to as "self-quenching". On barrels with enough carbon content, this will cause hardening, usually right along the weld edge or even on the weld itself. Many fluid steel barrels made in the early 20th century have enough carbon to harden, I suspect, since these are often early proprietary versions of chromoly. So, a normalize or anneal step can be used to get the steel back to a softness that can be filed.
Posted By: RHD45 Re: welding a hole in barrels - 02/27/11 01:42 PM
I am constantly amazed at the wealth of technical knowledge available from the members of this forum.Hell, it even makes me feel smarter!
Posted By: eightbore Re: welding a hole in barrels - 02/27/11 02:28 PM
How does all this translate into welding, heat sinking, and annealing Damascus? Annealing and hardening barrel steel makes me nervous, whether fluid steel or Damascus. What about leaving all of the annealing out of the equation and just filling the void in the area of the repair for strength?
Posted By: Chuck H Re: welding a hole in barrels - 02/27/11 03:29 PM
Bill,
Since the barrel is cooler, the weld will cause hardening all by itself if enough carbon is present. When I welded these barrels, I used mild steel rod. The welds themselves were ok to file, but the area right along the edge of the weld was very hard. I'm guessing something like 60 RC or more based on the way the file wouldn't cut it well. When you harden something, it creates stresses. This is especially true when you harden something locally and there is a disparity of hardening across the part. Given that the hardness was very high in my case, and that it was only local, I would feel much better about annealing than leaving it as it was. High internal stresses and high hardness is a bad combination for a part that will see additional loading stress. If you've ever seen a weld crack right in front of your eyes as it cooled, you have seen the result of internal stresses beyond ultimate strength of the steel.

If you're worried about annealing weakening the barrels to less than their original condition, I think you can lay that to rest. Barrels are relatively soft, except for a few exceptions. All this dent removal discussion is a good indicator of that. But the first time you see an engraver start scratching one up, that's conclusive.

I would treat damascus exactly the same for a weld. Weld it, try to file it, if it has hard spots, anneal.
Posted By: Steve I. Re: welding a hole in barrels - 02/27/11 05:02 PM
I agree with Chuck, if after repair you find the area around the weld to be hard to strike off, anneal it properly. Yes barrel steel is relatively soft if it were to hard, it would be very brittle. Just remember when undertaking a project such as this to use someone qualified. The brass internal chill bar will help with hardening as brass will soak up some of the heat and keep it from spreading outside of the weld zone. Filling the void between the bbls is not going to help that much unless you use something tougher that the barrel steel itself. I wouldn't recommend this as it will likely cause a violent rupture somewhere else. Ever seen a barrel fired on an ultra slow motion camera? Suprisingly enough the barrels actually expand ever so slightly and then return to original shape after pressure has tapered off. The elasticity of the steel allows this. I certainly would not want to compromise this with some kind of hard backing material. Just watch your hardness and test with a file, anneal if necessary.
Posted By: Last Dollar Re: welding a hole in barrels - 02/27/11 11:01 PM
I once bought a Fox Sterlingworth that had a weld about 3-4 inches from the breech. I didnt know it until, for some reason the spot changed color after some shooting..........The dealer I bought it from (local), didnt know it either and when he saw it, insisted on buying it back. He then cut the bbls in half and tossed them..."liability issues"...I thought it a terrible waste...
Posted By: Bill G. Re: welding a hole in barrels - 02/28/11 12:04 PM
I have welded a hole in a set of damascus barrels for a member here. The hole was less than 1/16" diameter. It was about 6" from the breach end. I ran an argon purge through the barrels and and used used a 3/32" diameter mild steel filler rod to plug the hole. I did not use a mandrill or heat sink. Using a large diameter filler rod you basically melt the rod first with it laying right on the barrel. As the rod reaches the melting point the barrel wall is so thin that it reaches melt also and the drop of weld just falls into place. If you get off the pedal quickly. The weld only takes a few second. You could touch the barrel with a bare hand a second or two later. It left a small dimple on the inside that needed to be polished down using fine emery on a wooden dowel. The barrels had plenty of wall thickness and after honing, which was done by the owner I am sure the weld was undetectable. Polishing the OD was a 5 minute job. I don't like using a plug for this type of repair. No matter what material you use some of the plug material will purge into the weld and that is no good. You are bound to end up with a weld that is not 100% filled or with porosity in the surface or both. With the argon purge you do have a small dimple on the ID but the weld is clean and 100%. As for the barrel described the hole is deep and the clean-up will be more difficult. And the bigger the hole the bigger the dimple. Also any type of heat sink is drawing heat away from the weld. When you are trying to weld fast and not cause a lot of heat drawing the heat away can be more trouble than it is a help. And if the mandrill is tight to the barrel any purge would be useless as it would sealed off from the weld area. If it were to get stuck it could be a disaster. If someone were going to try using a plug I'd take the time to make something that is collapsible.

Bill G.
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Posted By: bonehill Re: welding a hole in barrels - 02/28/11 06:21 PM
I have a crack starting just in front of the choke about 2" from the muzzle of a damascus barrel and have heard of micro welding. Is that better than TIG on damascus or about the same? :MIKE
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