Hi Anne
I spent a long time with this as I didn't have a vulvaniser nor a
wax injection machine. It is possible to do small run manual wax
injections with patience and very little equipment. Here's what
you'll need...
A depilatory wax heater available from beauty supplies for around
$50.
Two sheets of plywood held together with 4 thumb screws and a hole
drilled in the middle on one side ( to meet up with the opening in
your RTV mould). This looks like a flower press and is necessary to
apply enough pressure to force the wax into very small crevices.
Otherwise you end up with air bubbles and partial moulds.
A syringe, just the ordinary type you can buy from any chemist.
You put the RTV mould into your press, apply appropriate pressure.
Suck some molten wax into your synringe and inject it by hand into
your mould.
I had success casting wax bezel cups with this setup although it
does take practice and patience to get the process just right. It
took me about a week of constant casting to get everything just
right and it still produces a dud casting around 25% of the time.
But for a very low budget setup I think that's acceptable.
There is also a limitation about what kind of mould you can make. It
must be two part, and it can't exceed the size of your press.
Because the wax is not injecting at the same high speeds it would
from an injector machine the pieces also need to be fairly small as
the wax does cool very quickly. My bezel cups were about 2cm x 1cm
x.5cm. Also be careful because hot wax can spew out of the mould
onto your hands if you inject too much too fast.
I had very little success with commercial injection waxes. They
tended to be too brittle and too fast cooling to work. I used a
carving wax from a sculpture supplies place and had good success
because the wax was slow cooling and quite flexible when set.
Cheers
Claire
