It's called Sling Casting. I've done it with pewter. Worked pretty well. The
sprues have to be small enough that surface tension prevents the molten
metal from entering the mold by gravity alone. No larger than 14 gauge B&S,
you'd probably need more than one, I used 2 sprues to cast single rings, 3"
swords and battleaxes. Maximum flask size is suggested to be about 3"x3"
from the book: Practical Casting by Tim McCreight. I also like his book: The
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My dad, to whom I owe undying gratitude for pointing my eyes towards
technology, was born in Lodz, Poland. He learned jewelry making in
pre-nazi Germany, came to the US in 1921, and remained a jeweler all his
He told me about sling casting, though I never saw him use it. His shop
had a couple of hand wound spring driven centrifugal casting machines
mounted down inside galvanized iron washtubs, to catch any splatters.
The mainstream production method there was lost wax casting. As a kid, I
got pressed into making thousands of "waxes" of rings, bracelet links
and other doo dads. These were made using reusable rubber molds. We had
a smaller centrifugal machine for for making the waxes back then,
pressure injection of molten wax hadn't achieved popularity yet.
We also had a few multipiece metal molds used for making waxes. These
predated the rubber molds. They were made from a low melting point alloy
by craftsmen who encased a sprued "master" with modeling clay and then
carved away a section of clay and replaced it with poured in melted
alloy. They repeated the process until all the clay was replaced, and
through that process they created a multipiece reusable alloy mold.
Ordinary nail polish was used as a barrier to keep each successively
poured alloy section from fusing to the earlier ones.
Dad also told me about a technique he'd seen used in europe which
involved jamming several layers of wet cloth over the molten metal to
create steam pressure to help push the molten metal into a mold.
Thanks for the mammaries,
P.S. For those who might be able to use this information, there's a web
site containing Ellis Island immigration records:
I stumbled onto it a couple of years ago and was able to locate and
download the image of one page from the passenger manifest of the ship
which brought my dad and his family to America in 1921; and a photo of
the ship itself. They are framed and hanging on our kitchen wall. It's
nice to glance at it from time to time and reread the names of the
family members I knew as a child, all listed together line by line on
that manifest, and all categorized as "steerage" passengers.
Jeff Wisnia (W1BSV + Brass Rat '57 EE)
"My luck is so bad that if I bought a cemetery, people would stop dying."
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