After 20 years as a metalsmith this is new territory for me so I
thought I would seek the advice of those more experienced in
working with platinum and gold combinations. The proposed project
is to make a band ring with an undulating edge 8mm at the widest
point in 18k yellow gold with platinum laminated onto the
surface. I will pierce designs into the platinum before
lamination. My intention is to leave a small area at the back of
the ring without platinum so when the ring is formed I can use
18k solder for the seam. I am proposing to use 1.2mm thick 18k
yellow sheet and .6 to.7mm platinum sheet using a medium 18K gold
solder and laminate the two while flat then form the band. I
understand that I should stress relieve the piece after
lamination and before any further forming by heating and air
cooling. My questions are will this project work or am I heading
for an expensive ( lesson) failure and can I expect any more
distortion in the cutouts in the platinum than I get in using
gold or silver when I form the ring from the flat laminated ring.
Any other tips suggestions are welcome. Thankyou in advance for
any help
Douglas Frey
@d.d.frey
Dear Douglas, I know there are some issues regarding the
different expansion coefficients between gold and platinum that
you must take into account when planning a ring with these two
metals. Unfortunately, I’m not an expert on this! I’d suggest
you try calling Jurgen Maerz, director of technical education at
Platinum Guild International and describing your project to him.
I know he’s familiar with mixed metal work, and platinum is what
he does, so he can probably offer some (expert!) suggestions.
Platinum Guild International is in Newport Beach, California,
phone 949-760-8279. Jurgen’s e-mail address is jurgen@pgiusa.com.
Hope that helps!
Suzanne
writer/editor
SuWade@ici.net
Phone/Fax 508-339-7366
Dear Sir, a quick correction of my earlier response, I misspelled
Ronda Doering’s name. Oops. It is correct as it appears now.
Deborah Ringhaver Lane
Hello Douglas, Is it possible for you to bend each piece into a
ring shape prior to assembly? I think there will be less
distortion of your pierced design if you form a ring before you
pierce and then solder it. Good luck. Tom Arnold
Dear Sir, have you considered fusing the platinum onto the gold?
Ronda Dowering in Tallahassee Florida has granulating platinum
onto gold very successfully. She subscribes to this forum so you
might contact her. The beauty of fusing the materials together is
that you can avoid getting any solder into your pierced areas.
Good luck with your project. Sincerely,
Deborah Ringhaver Lane
Dear Douglas Frey, I laminate platinum over 18ct regularly and
(if I have correctly understood your description of what you wish
to achieve) would suggest that you will have less of a problem
with bimetal distortion if you turn up your 18ct band first then
turn up your platinum overlay and fit it tightly over the outer
circumference of the 18ct ring. The unbroken circular forms of
the 18ct ring and the platinum outer will resist any potential
distortion.
Use hard solder for the 18ct band and a good quality platinum
solder (I use 1020 or 1100 platinum solder) for the platinum
outer. Mark your respective joins in the 18ct and platinum band
so that you can align them when you fit them one over the other.
Doing a subsequent large resize (where you have to add metal
rather than hammer it up to size on a mandrel) on such a ring can
be a pain, but then most bimetal rings will present this sort of
distortion problem when subsequent work, which requires cutting
the band, has to be done. But I guess that’s what they pay us
for… Kind regards, Rex from Oz