Hello everybody,
Does anyone know of a caster who could cast some twigs? And does
anyone have any advice on how to weigh and convert to pennyweights
said twigs?
Thank you,
susannah
pregnant since 2004
Does anyone know of a caster who could cast some twigs?
Casters (such as Dan Grandi, Racecar Jewelry) may be able to cast
your twigs just fine, but when I did it myself, there was ash left
behind that made for poor castings. My solution is to cast twigs
myself, using sand casting (very low tech), cleaning them up, and
sending them to Dan to make a mold.
On the other hand, a caster could probably make a mold directly from
the twig, without burning it out. Never thought of doing that…
Noel
I have molds for twigs, if anyone needs cast twigs, e-mail me
off-line and I will send a picture of the different sizes I do, after
Christmas. If there is a particular size or type you want, let me
know.
Richard Hart
Hi Susannah
My experience in casting tells me that the twigs ( and I am assuming
these are twigs or branches from a plant ) are not going to cast
directly with a lot of success. They are very high in ash. That
leaves a heavy residue in the flast after burn out.
I would make a copy of the twigs using a 2 part or cold mold process
first. It will duplicate the twig down to the finest detail. Then you
can make a wax duplicate that will cats perfectly. You can use the
standard S.G. formulas to determine metal requirement from the wax
patterns, i.e 10.5 grams of S/S for every 1 grams of wax…
Good Luck
Dave
I use Larry Paul in Philadelphia. They have cast several twigs for
me and have done a wonderful job. But I don’t know about the
weighing.
Janet Kofoed
Noel,
Indeed, yes, Stuller’s newest RTV mold material can be used fopr the
twig project. It’s best use is for making molds of carved waxes,
which it will not harm. My brother at E-Wax, who mills waxes for the
trade via CAD, uses it for a quick route to multiples of extremely
detailed waxes which might take hours to mill otherwise.
Best regards,
Wayne Emery
The Gemcutter
I’ve cast hundreds of twigs from lots of different trees with very
good results in casting directly. First I dry the twigs for a month.
You could probably hurry that along by oven drying. Next I spray
them with an acrylic based transparent spray, dry for a day and then
tree them. I used to dip them in hot sculpture wax instead of the
plastic spray but found I had some porosity that way, which I also
liked since it added to the organic quality.
Donna in VA
Dear Susannah,
Does anyone know of a caster who could cast some twigs? And does anyone have any advice on how to weigh and convert to pennyweights said twigs?
I don’t think you quite understand the process here. When you asked
earlier about molds, you would have been talking about rubber or
silicone molds. These are the type that are either kept by the
caster, or shipped back to you with the casted batch.
It might be possible to find someone who would make a silicone mold
of a twig for you, and then inject it with wax and cast replicas of
it.
Most production casters for hire work only from rubber or silicone
molds, and do not burn out natural materials to make one-of-a-kind
replicas. These direct replicas would not have a reusable mold
involved, but rather a waste mold of investment (kind of like
plaster) that gets broken away to reveal the piece after casting the
metal into it.
I suggest that you read a good book on casting, such as Tim
McCreight’s Practical Casting, before trying to go too much further
into the casting field. It will really help you a lot if you know
more about the processes.
Artists you may have seen who are using twigs in their one-off
jewelry designs are probably casting them themselves. They will turn
out to be ten times or more heavier than the original twig. It
depends on how dried out the original wood is. Twigs can be
beautiful! But I made a piece last year that I had to trade off to a
friend because it was so heavy with cast twigs. My advice is: be
dainty with them!
Good luck with your work!
M’lou Brubaker, Jeweler
Goodland, MN
www.craftswomen.com
Noel,
but when I did it myself, there was ash left behind that made for poor castings.
I wonder if the species of twig makes a difference, or perhaps the
burnout temperature? I’ve cast from twigs a number of times, but
have always used alder. I’ve also cast alder cones with no problem
but when I tried to cast cones from another species, which I picked
up in Tennessee, I completely failed repeated attempts due to
apparently incomplete burnout.
Jerry in Kodiak
Hello,
I don't think you quite understand the process here. When you asked earlier about molds, you would have been talking about rubber or silicone molds. These are the type that are either kept by the caster, or shipped back to you with the casted batch.
I understand the process perfectly fine. I’m a certified casting
technician through the Texas Institute of Jewelery Technology, which
extensive experience casting carved one-of-a-kind waxes and regular
mold waxes. I have also gained experience in wax carving. There is a
method to my madness, here.
Yes, I was asking about having rubber/silicone molds returned to me,
so that if I so chose, I could modify the original wax- a
theme-and-variation approach to custom and production work that I
picked up in places I’ve worked. I asked about casting one-of-a-kind
twigs because I have no space for a casting setup of my own. These
were two seperate questions.
I know that organic materials can be cast effectively and accurately
because they were cast regularly in stores I’ve worked at in the
mountains. The trick is a higher than usual burnout temperature.
However, this particular plant part is a different type of wood
(palm seed-pod stem) and shape than the cones. Again, I have no
space for a casting setup of my own, so this is something I’d need
done for me.
Most production casters for hire work only from rubber or silicone molds, and do not burn out natural materials to make one-of-a-kind replicas.
I am aware of this, and that is why I was looking more for someone
with a setup. (Two seperate questions.)
I suggest that you read a good book on casting, such as Tim McCreight's Practical Casting.
This is one of the Texas Institute of Jewelery Tech’s textbooks.
Artists you may have seen who are using twigs in their one-off jewelry designs are probably casting them themselves.
Again, I have no space for a setup. I do know what I am asking for
here.
My advice is: be dainty with them!
Thank you for the advice.
Susannah
Indeed, yes, Stuller's newest RTV mold material can be used for the twig project.
And this stuff is called…?? (Thanks!)
Noel
Most production casters for hire work only from rubber or silicone molds, and do not burn out natural materials to make one-of-a-kind replicas.
I’d said before that Larry Paul in Philadelphia has done some twigs
for me, and also several small cones of various species. Here’s an
image of one of the twiggy pieces he cast for me.
http://www.angelfire.com/pa5/janet0/images/Rubytwigsm.jpg
It was a commission I had last summer. The client had given me four
rubies, about 100 carats total, and wanted me to include all four
stones in the piece. Since the stones were fairly large, the overall
design had to be large enough that the stones wouldn’t overwhelm it,
yet I wanted to keep the look light and airy. My solution was to use
twigs. I went through my garden looking for twigs that had a complex
branching structure at a small scale. This is made of two blueberry
twigs, joined with wax and cast. The settings were soldered in place
after casting and added more stability to the piece, since the twig
structure is pretty delicate.
I’ve given Larry and his people some very difficult challenges over
the twenty plus years I’ve been working with them, and they have
always done a wonderful job. If they have any questions or
reservations, I can talk to the person who will be doing the sprueing
or casting, and they will make suggestions as to how to make the
piece more castable, or get my input on where to put, or not to put,
the sprues. They are very skilled and very helpful.
Their telephone number is 215-928-1644. I highly recommend them
Janet Kofoed
Hello,
What does the acrylic spray do? Is it a lighter coating than
varnish?
Great idea about drying the twigs out. Thanks
Susannah
What does the acrylic spray do? Is it a lighter coating than varnish?
The spray (what I use is clear top-coat automotive spray) gives a
coating that seals the twig surface and seems to reduce porosity. If
the twig is thin, I use several coats to build it up. I’ve never
used varnish but any spray should do the job, even colored ones.
Donna in VA
The client had given me four rubies, about 100 carats total, and wanted me to include all four stones in the piece.
Correction: Reading over my last post, I realize I misspoke. I don’t
think they were that big. I confess I’m a little hazy on the whole
carat thing. But they were certainly big stones.
Janet Kofoed
Janet,
Thanks so much for posting the link to that wonderful twig/ruby
piece and thanks for mentioning Larry Paul in Philly. I’ve used them
for some challenging things, as well, and they rock! More jewelry,
less philosophy!!!
Wayne
I understand the process perfectly fine. I'm a certified casting technician through the Texas Institute of Jewelery Technology, which extensive experience casting carved one-of-a-kind waxes and regular mold waxes. I have also gained experience in wax carving. There is a method to my madness, here.
Oh, I’m sorry I misunderstood, Susannah…you seem to have a very
good background in casting!
You might want to keep a mold in your studio and send one to the
caster to keep, if they are going to to repeat orders of the design
for you very often. Otherwise, I find it is not too inconvenient or
costly to send them back and forth. The only things I really hate to
send are original models, since I really, really don’t want to lose
one of them in shipping! I keep my original models here.I have used
my models to make duplicate molds for my studio use of a number of
designs that my caster regularly does for me in silver, but a
customer wants in gold. I find it much better for my bottom line to
cast my own gold here, and the cost and time of making another mold
is worth it. (I often cast extras for my retail display, while I am
at it. Sometimes one’s customers are a great resource for ideas of
what folks want!)
Another possible trick is to use a vacuum cleaner to suck ash out of
the mold just before casting. This may work better in the
gravity-poured sculpture molds that have risers, but it might help
even in our dead-end jewelry molds.
I, too, have found that a very light coating of wax on the twigs
seems to help get the ash flushed out of the mold during burn-out. I
think I will try acrilic spray next time, and see if there is a
difference.
M’lou Brubaker, Jeweler
Goodland, MN
www.craftswomen.com
Dear Janet Kofoed,
See the necklace at: http://www.angelfire.com/pa5/janet0/images/Rubytwigsm.jpg
Thank you for sharing the photo of your twig necklace with us. It is
lovely. It is nice that Larry Paul (215-928-1644) is willing to cast
this kind of work for you.
M’lou Brubaker
Dear M’lou,
Thanks for the hint on having two molds: one for the caster, and one
for myself. I hadn’t considered that as an options, but with the
costs of shipping being what they are, it’s a good idea that would
likely pay for itself.
Thank you,
Susannah
Hi Susannah,
I just got a free moment to reply during this mad dash season. I have
been casting for about 30 years. I do centrifical casting by torch.
When I have worked with my evening students during these 26 years, we
have cast twigs of many different types…Some work better than
others, due to content of oil that particular piece may have inside.
Some types carry too much oil, like eucalyptus & pine–(although the
little cones are fine)…But, you always need to coat the outside of
the material with some kind of sealant, so the twig doesn’t start to
break down during the investing procedure. My stuff sets up fairly
fast but the water content in the solution can make the woody material
go mushy…So, I use either paraffin or a thin wax coating/dip first.
One lady even built up layers with Johnson Pledge Wax Spray. Then I
mix the investment as regularly and proceed. I do a 8-12 hour burn
out, usually at about 1100-1300 degrees and always check the spru
hole-no ash showing. We’ve done twigs,ferns, peanut shells, pistachio
shells & walnut shells…We have also done some flowers, bugs, and
other organic materials like popcorn. If you want to send me some
twigs after the holidays, I’d be happy to try to cast for you. I can
give you an estimate then.
Sincerely, Jo-Ann Maggiora Donivan
Maggiora Jlry. Co. 760 Market St. #959 San
Francisco, Ca 94102 (415) 362-4412