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.
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.
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.
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
Fusion welding is always a bit trickier than soldering, but not all
Set yourself up some ticket tests first, and get some proficiency at
it before tackling the real job.
On Fri, 23 Jan 2009 10:57:22 -0600, "Lloyd E. Sponenburgh"
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
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
Well, a pan the right size, and an oven that could reach melting temp comes to
pan with graphite to keep from sticking.
You didn't mention if you were laminating or making a butt joint, or a tee joint.
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