Platinum casting

I have been casting platinum with a Degussa motorcast machine for
about six months with good results. I am having a small problem
which I thought some of you might shed some light on. I have found
that after I cast 3-4 times the platinum begins to “stick” in the
crucible. It requires a great deal more heat to melt a similar mass
of platinum. Sometimes it seems it simply won’t melt, what’s up? I
am using Hydrogen/oxygen. Mark

I tested the Degussa Motocast for Ney about a year and a half ago
with Jurgen Maerz of the PGI…and it is a good little unit…except
for the outrageous price of it. You let the platinum “build” a
little in the crucible, and when cold, just take a sharp pick or
srewdriver and force it till it pops out. In the nozzle area of the
crucible when it gets too clogged, take a fine pair of
needlenose…grip the metal where it comes out hard…then slowly and
carefully start to twist the crucible in your other hand JUST
SLIGHTLY to get pressure. The “plug” will slowly turn in the nozzle
till it comes free and intact. This, however, works about 75% of the
time. The other 25% destroys the nozzle. Doc Robinson

Orchidians; I have a customer who wants a platinum ring made, using
his old platinum band to help defray some of the cost. Our usual
platinum caster doesn’t want to use the old band for fear of
"polluting" their own platinum. We suggested that that we would be
willing to pay for the extra platinum button and sprues, etc., but
it seems they only cast with large trees and so that wouldn’t work
out. Are there any platinum casters out there who would consider
taking this on? Or this something that is best avoided for some
reason? Is there some technical reason why you can’t mix old with
new platinum? Thank you for any and all help and -BK in
AK

Hello everyone, I am an amateur caster trying to widen my horizon
and include platinum in the range of metals that I can cast. I am
looking forward to attend a Platinum casting course during May 15 -
June end period, and am willing to travel over to another state if
need be ( from New York ). I have already completed a basic ( gold )
casting course and would really appreciate any feedback from this
wonderful community about the availability of any such courses
or/whether someone can teach me the practical aspects of the same( in
their existing facility )I am willing and ready to bear the tuition
charges if any. Take Care for now. Nilesh.

Niles, There is an abundance of available from Platinum
Guild International. Many papers are available with the latest
research on platinum casting, in the 2002 Santa Fe Symposium book.
There are several research articles that address sprue size, casting
temperatures, rotational speed and sprue configuration as well as
different investments. You will also need a hydrogen/oxygen torch.
Acetylene is not the fuel of choice for melting this metal. The
Neycraft Motocast Platinum caster is a great choice for several
reasons. First it has an enclosed casting chamber for safety. (very
important). It also has variable speeds from 350-450 rpm. The
slower speeds help in getting smoother castings with heavier pieces.
You will also need to use a high temp/strength investment and ALWAYS
ALWAYS use Platinum Safety glasses. The metal melts at white hot and
will damage your eyes if you don’t. If you need further assistance
you can call our technical support line at 1-800-545-6566 and ask for
the Technical Support department. We also have several articles we
can send you which may help.

Thanks for listening,
Phillip Scott G.G.
Technical Support & Sales