best way to weld together two 1/4" lead sheets?

OxyFuel torch

A blowtorch is just fine, preferably propane etc as the old pump up kerosine ones are dirty bastards. Use bar solder, use Stearine as a flux. Use a wiping pad made from an old felt hat (traditionally, rabbit fur) or failing that, a piece of motorcycle inner tube bent into a pad. Bevel the edges on the top sheet, wire brushing is adequate surface preparation.

You should be able to get bar solder and a block of Stearine from your local plumbing supply shop.

Andrew VK3BFA.

Actually, I was hoping to maybe epoxy the pieces together if it is possible. What this is is part of a lead container made up of 1/4" lead. Someone decided at one point to cut out a square slice out of one of the sides. I still have the piece that was cut out and it is only small and doesn't weigh much. With this cut out of the side, the container is pretty much useless and I first thought about welding it back in. I didn't want to use solder as the container is 100% pure lead and I want to keep it hat way. I don't feel good about heating it for fear of melting away the area where I want to weld in the cut piece.

Unfortunately, the lead is in a state of decay (MUCH oxidation all over the box), so I have been trying to handle it as little as possible and plan to place it inside 2-3 mil plastic bags once I have the piece back in place. I will still be able to use the box in the bags.

I have used 2 part store bought epoxies on other types of metals with pretty good success in the past and wondered, if I lapped over the joints and applied epoxy between them, would the mend hold? If epoxies can work, which would be the best?

Thanks in advance and thanks for the initial reply.

John

It's pretty hard to predict what will "hold," but epoxies (like most adhesives) don't do well on metals that develop weakly attached oxide layers, and lead is one of those.

Does the patch have to resist a force, or does it just have to hang there without falling out? If it's the latter, your two-part store-bought epoxy should do as well as anything. If it's the former, it gets more interesting.

-- Ed Huntress

I would try to use a copper backing plate and a big soldering gun.

And I would turn the box so that the backing plate is horizontal, below the lead.

Ignoramus31576 fired this volley in news:DpSdnbiYfv_rc-TUnZ2dnUVZ_t snipped-for-privacy@giganews.com:

Yeah... I'm surprised nobody just suggested cleaning and fluxing the lead, and fusion welding it with a big iron, or a very small torch running a reducing flame.

Ig's right about having a heat-sink surface behind. You can always weld from both sides, but having a melt-through would be unfortunate. Make sure the surface of the lead is in intimate contact with the heatsink all along the joint. You can re-form the container wall after welding.

Fusion welding is always a bit trickier than soldering, but not all that difficult.

Set yourself up some ticket tests first, and get some proficiency at it before tackling the real job.

LLoyd

That's what I would do, I cannot imagine why it would not work. Of course, it should be done in a flat horizontal position, backing plate on the bottom, lead on top.

The backing plate would address melt-through nicely.

Lead is a nice material to work with, I cast a lot of it when I was a kid (probably not too healthy)

on the other hand, lead may fuse with copper. Maybe aluminum will be better. I would definitely experiment.

Ignoramus31576 fired this volley in news:Zqudnf-tmtU5bOTUnZ2dnUVZ snipped-for-privacy@giganews.com:

It will. But you're supposed to control the penetration to extend about

LLoyd

I'd back it with petrobond casting sand. That will mold to the shape of the object and it will prevent melt-thru without sucking heat out of the joint. Think of it as casting-in-place.

There's also some ceramic jigging putty available from Eastwood that works well.

Well, a pan the right size, and an oven that could reach melting temp comes to mind. Rub pan with graphite to keep from sticking.

You didn't mention if you were laminating or making a butt joint, or a tee joint.

Wes

Back in the day when Telephone companies used lead jacketed cable they would cover the splices In lead. The procedures used was to slip a lead tube over the cable and then do the splice. Then they would use molten lead and a insulated glove to "wipe" the lead to make a transition between the cable and the covering lead tube. You can (I think) do something similar using a big Iron or liquid lead

Bill K7NOM

Uh, I gotta ask. What are you using a lead container with 1/4" walls for? Smuggling something, perhaps? :)

Jeff