Tungsten for welding contains 5% thorium. Thorium is used to coat
tungsten wire used in electronic equipment, improving the electron
emission of heated cathodes. I don't know how this will react with
silver solder or with pickle.
I’ve never noticed any adverse effects, though i’ve not especially
looked. Among other things, I don’t use my solder picks in the
pickle, so that’s unknown. I’m not suggesting tungsten for anything
but the high temp operations, ie solder picks, since that’s all I use
them for. It might work for other things, but it’s main advantage is
simply that it won’t flare up unexpectedly and burn, like titanium
can do with a thin rod or sharp point, if you get it hot enough (and
platinum work is hot enough).
I've used tungsten picks before from suppliers and found that
silver solder would melt onto the pick. Maybe it wasn't pure
tungsten, but again it's the consistent and repetitive heating.
You’re right, it will, if fluxed. I’ve never especially minded this
when in moderation, and by not getting flux on the pick, plus
oxidizing it first, it’s not a problem. Any solder that does flow
onto the pick is not contaminated by the pick, so far as i can tell.
I just figure occasionally needing to dress the tip is a small price
to pay for a pick that will withstand the temps I need to use it
with, and once comfortable with it for one use, I tend to just use
them for all soldering.
However, you are right, I haven't fully explored this yet and I
will give it a try. My husband has some in stock as he owns a tig
welder. The width of the welding stock is wider than the thin rod
you get from jewelry suppliers.
yes, you can get the tig rods in a number of weights, from very thin
delicate wires, to rather heavy (1/8th inch or so). Lots of options.
I do know that tungsten for welding rod it is a consummable and
that there are 6 inch rods and which can be ground down. I do know
that you cannot put any pressure on the rod itself.
That depends on the size rod, and what you consider pressure. If
you’re doing large holloware and need to force a rim into position,
this might be too much, but I don’t know. My own work with tungsten
picks is all “jewelry scale”, and I’m not in the habit of needing to
wrestle the metal around with the soldering pick. Modest pressure
seems fine. I’ve never had one snap or bend while in use.
It also oxidizes easily.
Which I encourage deliberately, is it limits solder flowing onto the
Tungsten is a very brittle metal, excellent for welding, but for a
six inch piece for continuous use, I will have to do more research.
As I said, though it’s described as brittle, I’ve had no problems
with the things breaking, at least not in use for soldering. There
was one I snapped while using it, inserted in the cross hole of a
stuck hammer handpiece tip, to try and wrench the tip off the hammer.
That, needless to say, was more than it could stand. Two of the old
steel busch burs I also tried, also snapped off, before the third one
did the trick…
Thanks Peter. I'll look into this.
You’re welcome. Hope you like em.