Call PM West (800-999-7528) and get some of their new quick set
platinum investment. You can invest, burnout and cast within one
hour! I have seen it demonstrated twice now and it looks like the way
to go for platinum casting. It has been used with platinum and gold.
I have not seen the surface finish on gold but the castings in
platinum are superb in finish. There is an article in the August AJM
about this investment and stone in place casting with platinum and
diamonds.
Jim
jbin@well.com
James Binnion Metal Arts
4701 San Leandro St #18
Oakland, CA 94601
510-533-5108
I used to work at a wholesale jewelers and part of my job was to
polish and re-plate repairs. This was when rhodium plated white gold
was very popular. I agree with David that rhodium plating looks garish.
However I don’t remember having a problem with a sizing showing after
I polished and re-plated and I’ve always been known as somewhat of a
perfectionist. I may not remember correctly because it was a long time
ago, but our shop did generally better work than most (even though my
boss was known to use cheap castings and stones at times, with the
jewelers’ objections.)
Patricia - from San Diego where the electric bills are outrageous.
That’s all I wanted to hear. I figure, when I’ve used the palladium
casting grain I’ve got, I’ll give the Stern-Leach alloy a try, or
call United (where I get my casting grain, usually) and see if they
have a comparable alloy. I can still use the palladium in
fabrication situations. Two questions more, if you would bear with
me. 1. does the Stern-Leach alloy require any special casting
considerations as to investment and method of melt? 2. can it be
soldered with cadmium containing solders or does it require the
cadmium free stuff?
Thanks again. I hope sometime I’ll have some that can
help you in some way in the future.
By the way, Patricia, are you related to John Atencio, the designer?
I like his work. I can recognize it anywhere. Him and
John-Fran�ois Albert are doing stuff that has always really appealled
to my design sense. I’m probably picking their pockets more often
than I’d like to admit (mind you, I didn’t say “knocking them off”. .
.rather, designing along the sames lines of sensibility, economy, and
elegant proportion).
If you’re not working with rhodium plated goods a lot, you might miss
it. Once you’ve seen it, you can’t ignore it. What happens is this.
The rhodium gets abraided off the area where you size the ring,
naturally. Now you go to polish it, and the white gold, being
softer, comes up nicely. However, where the rhodium starts, it’s
foggy looking. Rhodium is harder than white gold, and if it’s a
heavy coat, it’s not going to come off easily. I’ve had to rubber
wheel the remaining rhodium off, polish, and re-plate. Fine for
simple shanks, not so easy where there are complex surfaces. Anyone
out there seen this or am I wearing to much magnification?
I have a couple of pieces of John Atencio’s work I bought back in the
70’s from his shop in Ft. Collins, Colorado. They are among the few
pieces of other people’s work that I still wear and enjoy. I looked
up his web page. Nice to see what he’s doing now. Still designing with
the same elegance that appealed to me many years ago, before I even
thought of becoming a jeweler.
It’s exactly what happens to me. I hate it when they bring me a ring
for resizing. I have to sandpaper the ring to remove the old plating.
But I don’t do it all over the entire ring. Just the part I’m sure it
will not plate well if I don’t remove the old plating. Then I
re-polish and plate again. This foggy area between old and new
plating, you don’t need magnification to see it, it is so obvious and
ugly (at least for perfection-oriented people).
Two questions more, if you would bear with me. 1. does the
Stern-Leach alloy require any special casting considerations as to
investment and method of melt? 2. can it be soldered with cadmium
containing solders or does it require the cadmium free stuff?
David,
I haven’t found any special requirements other than what I have
written concerning the flask temperature. I have used torch melting
in a regular ceramic crucible and I have cast using my automatic
electo-melt which as I’m sure you know utilizes a graphite crucible.
I happen to like using the electo-melt myself due to the ease,
convenience and consistency. I use satin cast 20 from Gesswein and,
again have had no investment related problems.
I really can’t stress the need to get the flask temp. down as low as
possible, though. It took me a while to find the right temperature
level (had a couple of incomplete casts). If the flask temp is too
high the gold will stay molten too long and you’ll get a lot of
brittleness, especially near the sprues.
As to the use of cadmium solders, I haven’t heard of any need not to
use them, however, I buy my solder from Hoover and their white gold,
and silver solders contain no cadmium. Other companies white gold
solders may contain cadmium but you will have to ask your particular
supplier. Anyway I don’t think cadmium has any affect on the metal.
