I have heard that Titanium, Tungston and Tungston Carbide are
all materials that can be used in connection with working
Platinum. I tried using a Tungston soldering pick once, but it
looked like it was fuming a black smudge onto the platinum ring I
was working on. So, I stopped John Burgess told me that Tungsten
melts at 3410C; Tungsten carbide at 2870C Silicon carbide
at 2700C. But someone else told me that Tungston Carbide melts
at about 2700 F depending on if it was sintered with Nickel or
Cobalt and how much was used. (I have always been a little
confused about Farenheit and Centigradeanyway) I am pretty sure
that Platinum Iridium melts at about 1740C so it would make a
huge difference whether it was C or F. I’d like to find a material
that I could stir or pick solder the molten platinum and not
worry about contamination. Does anyone pick solder Platinum??
Thanks, John
Perhaps a quartz stirring rod, found in the Gesswein catalog in
the casting section. They might know for sure if this would be
safe.-Brian Charles
John, for what its worth I found a URL which lists metals and
links to their descriptions. The physical constants are shown
under each individual metal’s description. Juat click on the
metal name. Geo…
m016001530f .asp
John, I bought a pick from a local supplier and it was supposed
to be tungsten carbide it worked ok for lower temp platinum
solders but when I use 1700 platinum solder it started turn black
on the end and melt a little.I have been either fusing or
sandwiching solder that I roll out very thin in my rolling
mill.If I do use the pick I will tack the solder to the seam
first and pull the pick away carefully and melt.One problem in
trying to use a pick is a surface that won’t melt when picking up
your solder.I use a grs system and the pads they sell don’t like
a lot of heat. Best J Morley Coyote Ridge Studio
John Caro: I have Soldering picks made for Platinum using
Niobium, the tempature is some where in the 4000 degree F. range.
We sell them for $6.50 each.
Charles Eichhorn
www.eichhorninc.com/dlromey
@D.L.Romey_Company
Titanium burns too easily. The sharp point on a pick will give
you surprisingly bright flares with sparks and much excitement at
platinum soldering temps. Tungston carbide works, but the solder
sticks to it easily. Plus, it’s real easy to break a thin
carbide rod, and it’s hard to find thin stock too. I prefer
tungston metal rod, which I get from welding suppliers as TIG
electrodes. Used clean, they’ll smudge, though only a surface
"smoke" that doesn’t hurt the platinum. Sharpem the pick, then
heat it without solder nice and bright for a few moments, to
pre-oxidize the tungston. Then it doesn’t smudge the metal so
much.
also, don’t forget that you can use a piece of platinum wire
just as well, when feeding in platinum solder. With 1700 solder
that gets iffy, but with lower grades, it works just fine. I do
that when soldering platinum chains. Because the solder flows
out on the platinum “pick” wire, getting just a minute amount of
solder to transfer from it’s quite happy position on the pick
wire over to the joint, without flooding the joint, is a lot
easier than trying to cut a paillon small enough so that when
the whole paillon flows into the joint there isn’t then too much
solder…
Peter Rowe