Dear friends from Orchid; I own an small jewelry fatory. All of my pie=
are casted. With a recent trend, here in Brazil, of white gold, a grea=
portion of my production is done in this metal. But I am having a har=
time with porosity. I’ve been using niquel as alloying metal. I use an
induction Manfred centrifugal casting machine(italian)with vaccum in t=
chamber and I’m not using argon in the chamber, although I could have =
using it. The tube casting temperature of 550=BAC(1022=BAF). Gold temp=
of 1050=BAC(1922=BAF). Could someone help me? Thanks. Sergio Bernardes=
Dear friends from Orchid; I own an small jewelry fatory. All of my pie=
Sergio, I would definitely recommend pumping argon into the chamber if
possible. Also, consider a switch to Palladium alloyed white gold, which
is more expensive and has a higher melt temp, but you’ll make the money
back in finishing the pieces. The only other thing I can think of is a
re-examination of your spruing process. Good luck, Mike.
Sergio, I suggest you contact the people at United Precious Metals (I will
send the phone and address in another post) they are great about working
with you to get just the alloy for your needs. I have forund over the past
25 years that the alloy has a LOT to do with the quality of casting and the
people at United know what they are about. (Usual disclaimer goes here)
Hi Folks, I’ve been here…reading this and that. I haven’t had time to get
into writing for awhile as we’ve been knee deep in putting the final
touches on our gallery (Sterling Gallery at the J.A.Henkel Co. Inc.) Having
cast white gold (14k & 18k)for years and years I hope I can de-mystify the
process for you. Good alloy is a good place to start, and the are many good
alloys from all the major metal suppliers, however there are some basic
do’s and don’ts. The nickel in the alloy doesn’t like carbon…so dont use
graphite crucibles or stiring rods. If you are torch melting, use a
slightly OXIDIZING flame. You want to hear a slight hiss. Flask temp is a
little higher than that for yellow gold, by 100F. Once again if you are
torch melting, don’t preheat the crucible much, about thirty seconds should
do it. Your flask should be in place before the metal is half way melted.
When the metal is pulled up away from the sides with a slight red glow let
it spin. If it gets closer to yellow in color or whitish yellow you’re in
trouble! If it lets off some white smoke it’s too hot. As for induction
melt vac machine, nitrogen or argon will help but use a ceramic crucible if
one is avaialable for your machine. If you’re casting 18k Paladium white
you’ll need some high temp investment. If you’re in Bruswick, Maine, stop
by our shop where we brag on our casting customers by diplaying their
finished work. We’re at 16 Union St. Or call 207-729-3599…Moldmaking
Casting Finishing … J.A.
I am new to jewelry making, I am making an engagement ring for my
girlfriend (something of a family tradition, my cousin’s husband
made her ring as well). I need some advice on casting white gold, I
have found lots of advice but some very important areas are left
unclear. For instance, what torch and fuel should I use to melt the
casting grain, and in what type of crucible? How long should I heat
the metal, slowly, quickly? What sort of investment would you
suggest? I’ve seen a lot of more advanced discussions but not really
any introductory ones. I went to the library today but the selection
of books on jewelry was pretty terrible, outdated and vague even
fifty years ago. I am probably going to be working without rhodium
plating, so what karat of white gold would be best? I apologize for
the mass of questions all at once, this is the accumulation of about
two weeks or research in one message. Thanks for any help.
Get the book Practical Casting by Tim McCreight.
I need some advice on casting white gold,
Probably you’ll get much advise - my advise is not to worry too much
about it. Every metal is cast in a “superheated” state - “when the
surface is swimming”. It doesn’t matter if it’s silver, bronze, or
platinum, when you get that effect, it’s time to let it fly. We cast
everything but platinum in the same standard ceramic crucibles, and
don’t do much different for any metal in the casting process - heat
it to the same “look” (when the surface is swimming), which will
vary for the metals, but will look the same under the torch. And let
it fly… There’s much debate on when to quench, but we find that
white gold does well when it’s quenched in about 5 minutes or less.
If you let it cool to room temp. it might be rock hard when it comes
White gold has some issues in fabrication, for sure, but it’s really
no big mystery to cast…
With 35 years of experience casting I have learned that it is a very
forgiving process. Have you done any casting in the past? If so what
experiences have you had with the methods you have used? If you have
had good results casting other precious metals such as sterling or
other colors of karat gold than doing white gold will be no
For me I use an oxy/propane torch for casting and it works well for
me. The crucible to use for white gold is no different than the ones
used for sterling silver or other colors of gold. It is a standard
clay/silica casting crucible. As for melting the metal I like to use
neutral or slightly hotter flame depending on the amount of metal
Quenching should take place after the button is no longer red (
generally about 10 minutes after casting ).
Stuller settings has a white gold that they call X1 which gives a
fairly good white color but does have a fair amount of Nickel alloy
in it. Another choice would be an alloy with Palladium.
The keys to getting a good casting is based on some simple processes.
Make sure you have sprued the piece properly, A proper burnout cycle,
don’t overheat the metal and the one thing that has worked best for
me even casting metal that has been melted multiple times without
fresh metal being added is to use at least 50% more metal than the
piece with sprues require. I like to use the rubber bases that create
a large reservoir ( Rio calls them a donut design ) which allows for
a large button for the casting to feed off of. I use Satin Cast 20
investment for all of my casting.
Hope that helps.
Hi Will, congrats on your engagement.
My suggestion to you would be to find a reliable caster and have
them cast your wax. You will then not have to worry about a lot of
the beginner’s problems found in casting - particularly white gold.
If you are concerned that the ring won’t have your personal touch
don’t forget that you will have designed it and done all of the hard
work in cleaning it up.
All the best and good luck,
my white gold castings started coming out much better after i
switched to using R&R ( ransom and randolph ) casting investment if
you google them you can get a phone number and call the company
direct i am using one of the higher temp investments cant remember
which one off the top of my head, it has a plasticy feel when
mixed and it always sets up very hard and the micro porosity seen in
alot of white gold is almost nonexistant now. i am using PM west
100ND white alloy as opposed to high nickel white and have very good
results now compared to when i was using other products - goo