Casting "filigree"

I am trying to design and cast a peice on CAD/CAM and have been told
repeatedly that I can’t go any thinner than 2mmx2mm of wire
thickness for a “filigree”-type design. I received the completed
peice from my fabricator, and it’s REALLY heavy and completely
unusable. How are people able to cast designs with fine filigree
work in them? Is there something I’m missing? I’ve looked online and
seen many pairs of earrings close to what I am doing, and I can tell
it’s a cast peice because the earrings are exact replicas of one
another. Any thoughts would be greatly appreciated!

Jenny

Jennifer Kaufman,
Jen-uine Jewelry
www.jenuinejewelry.com

Jen, I cast filigree all the time…that is my specialty!..there
are tricks to it, but my original wire that I use to make filigree is
1X0.5 mm! You just won’t find many casters willing to go that extra
mile. In fact, when I bought my casting equipment a couple of years
ago, I called the company saying I just wanted to make sure I was
getting the best suited equipment and supplies for casting filigree!
the reaction was like “you’re going to cast what?!?!?!”.

In any case, part of it has to do with creating a design that the
silver will flow into even with fine wires. you can’t have a design
that is too large, or where the design is too complicated where it
will flow against the flow of the silver. I also use a 1x1 mm
framework of square wire on my filigree. This 1x1 framework makes it
more structurally sound, but also makes a flow channel through the
piece. You need to have the filigree densely enough designed so that
the silver will flow from one end to the other.

I use blue plasto-wax, even though there are waxes meant for fine
work, I like the plast-o-wax because it is sturdy and flexible enough
to pull out of the molds. Use low shrink silicon mold
rubber…Silicon is self releasing…don’t hold your mold too hard
when injecting waxes or it will cause flashing inside the filigree,
but not too loosely either or you’ll get it shooting out the
sides…this took me a while to find just the right pressure
intuitively.

when treeing the wax, think silver flow…always think about where
your flow will be. I set up trees with an average of over 50
components on each with filigree. Last casting I had one tree that
came out 100% with no partials and most of mine are about 90% give or
take.

Lastly, casting temp…much higher than usual. My first attempt,
using vaccum casting was a disaster. The silver froze up before it
could fill the fine designs. You have to compensate more with vaccum
than with centrifugal for the rate of fill vs speed of cool down as
it flows through the fine patterning. I cast at 1150 deg. F flask
temperature. and my electromelt brings my silver temps to about 1920
deg F before casting.

So yes, it is possible. I have some pictures of my last raw
casting(trees, waxes etc) to show how possible it is. I will try to
post them online later… look at http://jeannius.com/cast/ and you
can see the fineness of pieces that I am casting. it is entirely
possible…but the attitude you’re talking about from the casting
houses are exactly the biggest reason I do my own casting! Even if
they were willing to do it, the extra time involved by them would
probably jack the price up a lot!

BTW. I think a lot of the fine filigree components you see sold are
done by stamping rather than casting.

Jeanne Rhodes-Moen
jeannius.com

have been told repeatedly that I can't go any thinner than 2mmx2mm
of wire thickness for a "filigree"-type design. 

Jennifer, you need to never, ever, ask those people for advise
again. That is about as clueless a statement as I’ve ever heard. You
can cast ANYTHING if it’s properly sprued - if it’s castable
material, obviously. 2mm square or round is HUGE… In a wirework
situation, what you need to pay attention to is two things: First is
that it is plumbing. Metal will flow from bottom to top, and all the
pipes need to touch each other, and fill each other. It’s pretty
obvious that some element that’s not connected to the flow will not
get metal. Real filligree can be made any way because it’s soldered.
Cast wirework needs to be designed with the flow of metal in mind.
Second thing is that you need to have even thickness - not meaning
the wire has to all be the same, but if you hollow out the ring or
do waxwork you need to be sure you don’t have greatly thinner spots.
Hand in hand with that is that all the joints have to be positive -
no air where wire touches wire, whether it’s a soldered model or
waxwork. Just visualize a wave of metal coming from the sprue, and
make sure that the wave can find every nook and cranny. To some
degree you might avoid having thinner stuff towards the sprue and
thicker after, or you’ll get “the coke bottle effect” (open a bottle
of anything and quickly turn it upside down and watch what happens)
2x2mm - that’s funny… People cast houseflys and butterflies all
the time, with a sealer put on them first…

depending if your going to cast directly or make a mold but you can
defintly go thinner plus you need to take in consideration any
shrinkage that might occur and the polishing no problem doing
1.1-1.2mm you can have certain parts thinner but it all depends on
your design

Very impressive and generous of you to share what you’ve discovered.
One clarification: are you fabricating the originals and then
molding? The results look good.

Real filligree can be made any way because it's soldered. 

There is also subtractive filigree, were the piece is formed and
then the filigree pattern is cut in with very fine saw blades. I use
#6 blades, cutting shapes formed in 18g sterling. This allows for
different kind of filigree look, were in, the thickness (as viewed)
is changing as well as the shape of the “wire form”.

Dan

Very impressive and generous of you to share what you've
discovered. One clarification: are you fabricating the originals
and then molding? The results look good. 

Yes, I make the pieces by hand first, using 1x0.5 mm textured
filigree wire and aproximately 1 mm square wire (depends on what I
have handy, sometimes I flatten thick round wire in one direction).

Jeanne

in my casting in July, I took some pictures of the casting process
so I could put them on my website…I just made a quick page with 6
of these, showing the wax trees, the cast trees, and the cut and
pickled components. You can see the kind of detail I’m getting
casting filigree by going to"

http://jeannius.com/castprocess/

Jeanne