Weld strength

[historicalarms]

I need to do a repair on a double shotgun hinge latch lug and am wondering wich weld method would be stronger, tig or wirefeed. It will be asmall piece of mild steel prob .125 in thickness and 3/8 x 3/8 in size so heat burn-out will be an issue. old edges of the latch will be v'd or grooved for weld penetration.
I wont be doing the weld myself, I want it done by a very experienced hand at either method, whichever you guys tell me is best.

 

[PeterT]

Are you considering welding this part standalone (ie. re-make the part) or welding it to another part? Pictures would be helpful.

 

[SomeGuy]

TIG will have better heat control if the person is experienced. I'd want to provide them material of similar size/thickness/shape to test on to dial in settings before doing welding on a critical piece.

 

[DPittman]

If done properly both can be equally strong, but id prefer the TIG for aesthetics. Oxy/Acyt can also be an option but that is sort of old school and also requires unique skills.

 

[Susquatch]

Paging @thestelster. He has likely done this and experience is king.

 

[Bandit]

May need to be careful of heating the area, some I believe may have the lug silver soldered on, somewhat age dependent. Do not hold me to it though. Tig will likely be stronger, material, rod and welder dependent, can have better control of weld and heat. all the above can apply, tig could allow area to be built up and reshaped also.
Much will depend on if the piece will be used again, or a wall ornament.

 

[Ironman]

Tig it.

 

[historicalarms]

Are you considering welding this part standalone (ie. re-make the part) or welding it to another part? Pictures would be helpful.

welding to the existing locking lug. I need to re-new the lock surface so a tighter closing latch-up is attained.

 

[historicalarms]

May need to be careful of heating the area, some I believe may have the lug silver soldered on, somewhat age dependent. Do not hold me to it though. Tig will likely be stronger, material, rod and welder dependent, can have better control of weld and heat. all the above can apply, tig could allow area to be built up and reshaped also.
Much will depend on if the piece will be used again, or a wall ornament.

The original lug & hinge plate are a solid one piece so not a worry.
The piece I am adding will be the "build-up piece" that will be filed/milled to re-make the latch-up a bit tighter...as it is now , the chambers have 20 or 30 thou looseness when closed and the latch will allow the action to pop open when firing a factory target round ( I can handload light loads that wont open it up but think it should still be tightened up a bit.
Definitely gonna be a "used again" item

 

[thestelster]

I'm not familiar with what you are calling the latch lug. But on most double shotguns the lock plate or lock bolt which is actuated by the top lever under spring tension and locks the barrels tight into the action. If it's this part that you are referring to, then I tig weld. I personally use H12/H13 filler rod, but it's really hard so grinding is the way to reshape. Or you can use P20 or P20modified, which is a little softer and carbide tooling will work, but might need to use some stones for a good finishes.

But I use tig on all gun related stuff. I have a guy in T.O. who micro-welds. Tig under a microscope, the filler wires can be as thin as 0.010". There is also laser welding, but way more expensive, and usually not needed for most gunwork.

 

[thestelster]

allow the action to pop open when firing a factory target round

Most of the time, not always, but the main culprit for the barrels opening up is the top lever spring strength.

Now if you have as big a gap as you mentioned, then the lock bolt doesn't have enough engagement to the barrel recesses and pops open. Similar to too little trigger sear engagement.

 

[Ian Moss]

I do not work on guns, but am a fan of silver soldering. Can be very strong depending on the physical configuration of course.