I would like to make my own crucibles for Silver, Gold and Pewter.
Fairly small for up to about 4 oz
Also, a friend of mine has two crucibles obtained from Mexico. They
are call Tortuga’s. Anyone know where to purchase them, or how they
are made and what materials to use.
RLW
What an interesting subject…I can think of several applications
that would be useful to me.
( I’ve got some antique casting machines that need crucibles.) When
I was in Ghana, Africa I encountered native made crucibles used in
casting brass and gold. They appeared to be quartz with an unknown
binder and may have been shaped by hand. It seems to me that
carborundum would be an excellent substance for use as a refractory
if one could figure out what to use as a binder. ( Beats the hell
out of using it for making Moissanite )
Ron Mills, Mills Gem Co.Los Osos, Ca.
Maybe this will help you !???
I just finished a week-long workshop with 3 African silversmiths
(Mali, Burkina Fasso, Niger, one of them being a Tuareg). It was a
wonderful experience working with so little equipment and obtaining
such a perfect technique.
We used only a small charcoal fire and a pair of bellows made of
goatskin (legs still attached). No problem to melt silver (no
discussions on propane versus butane or acytelene …!) and pour
ingots.
They used tamarind (a pod like plant) + salt as a pickle
3.(the most interesting !!!) As casting investment we used …
donkey donk: make your model out of wax, put the donkey dunk
carefully, little by little around the wax, let it dry near the
charcoal fire for a day, melt the wax and pour it out (and re-use it
of course), put the mold in the fire , melt the silver, pour it in
the mold and there you are!
Of course time was not of any importance but what an enriching
experience!
Greetings to all,
Linda (Belgium)
I just finished a week-long workshop with 3 African silversmiths (Mali, Burkina Fasso, Niger, one of them being a Tuareg). It was a wonderful experience working with so little equipment and obtaining such a perfect technique.
Hello Linda,
Great post! That must have been a very cool experience. I love
hearing about how non-Western smiths go about there business because
so much of it is possible in a low-tech/no-tech shop like my own.
2. They used tamarind (a pod like plant) + salt as a pickle
FWIW, the fleshy part of the tamarind is high in natural citric acid
so basically they’re using a citric acid pickle with a salt booster.
(I’ll have to try adding a little salt to my citric acid pickle to see
if changes it’s effectiveness.) As you may know you can buy tamarind
at almost any Asian or Indian grocery store. It comes as a cake of
pods mashed into a small brick, seeds and all. I use it often in my
other preoccupation: Indian cooking.
Cheers,
Trevor F.
in The City of Light
Dear Linda,
Thank you for the wonderful - did you go to north Africa
for the workshop? Would love to get the resource for
this.
I really enjoy reading about and trying low-tech techniques for
metalworking especially (and many other things, like making bows and
doing leatherwork and glasswork). I’m always a bit overwhelmed and
amused by the amount of techie stuff out there for metalworking (and
I use a lot of it!) and of course beginners who are convinced they
need a $30,000 state-of-the-art studio to start out.
Your workshop description sounds like the early Navajo silversmiths
out here: a tree stump, hammer, saw, local carving material for
molds, and tools made from old steel parts from the yard, forged into
stamps and crucibles and the like. Some of my favorite jewelry is
this old stuff.
Thanks again for sharing. I suspect some of the beautiful work and
creativity that one sees in low-tech fabrication comes from the fact
the maker is not spending time worrying about the technical stuff
(like discussions about butane vs propane vs acetylene) but focusing
on on the art!
Roseann
Lindsay’s Technical Books has a book, Making Crucibles by Vince
Gingery. Mostly about the size crucibles used for sculpture, but
size can be adjusted. Has on making molds to duplicate
the ones you have. If you have a kiln you should be able to fire the
clay.
I once took a class in viking age casting techniques, where we made
our own crucibles of horse manure, clay, and sand. They were dried
next to a camp fire for a day or two and then fired and could be used
right away. I’m not sure about the ratio, but I can still recognize
the feeling when the mixture was correct. I think it was about
40/40/20, where sand is the The same mixture was used as casting
investment, clad around a sprued beeswax model, dried, burned out and
cast. Most time really went with the cleaning up of the castings
afterwards.
Why not try it and let us hear about your results.
Niels Lovschal,
Bornholm,
Denmark
This thread was my post a long time ago. I’m still looking. I tried the suggestions to construct my own but NO JOY. They wouldn’t bind very well. Cleaning out some boxes I found one that had been packed away. Perhaps someone has seen them and can point me to where I can purchase. The individual that introduced me to them called them tortugas and said they were from South America or Mexico. He has passed on now.
Regards RLW