Ok Jon this is a short summary of the process as I understand it ...Most of
this information comes from a very good (excellent) book on this topic
called "Centrifugal or Lost Wax Jewellery Casting" by Murray Bovin.

A shape can be designed using a cad package such as rhino etc etc
This can then be converted to Gcode which can then be processed by Linux EMC
which drives the CNC mill.

Carving wax is mounted and the mill set in motion once completed your
desired part should be replicated in the wax.

This wax part is hung inside a flask(a tube) to be eventually surrounded by
investment.

Investment is composed of cristobalite, gypsum, silicas and modifying
agents.
cristobalite is a volcanic mineral. It is now made by heating silicas to
2680C - 3040C.

One problem with investment is air bubble's the solution is to vacuum them
out by placing the investment inside a bell jar.

The slurry (investment) can then be slowly pored into the flask containing
the wax part once this process is complete burnout can take place. Burnout
removes the wax leaving the impression in the solid dried investment.

This can then be placed in the centrifugal casting machine ready to receive
the molten metal.

Once the metal is in place a pin is pulled sending the clockwork centrifugal
arm rotating which forces the molten metal into the investment. Once cooled
the investment can be removed hopefully leaving the finished part intact.

Note : you could skip the steps of designing and cutting the wax part if you
have a piece to copy by taking an impression of it in rubber then poring
molten wax into the rubber mould. This would give you your lost wax part.
Alternatively you could carve the wax by hand as many Jewellers do or at
least they used to.

Hope this helps Jon forgive me for any unclear rambling ;-)

Regards
Steve




"Jon Elson" wrote in message
...


sme wrote:
BoDiddly thanks for your interest,

I think it would not be unreasonable to say that stock of around 30-40mm
dia
could be worked.
This could be placed in a small removable crucible of which the work
coil
surrounds Eddie currents will then be induced into the workpiece which
acts
as a primary single coil (high amps) this causes friction that heats the
piece and eventually melts it.

This setup would be ideal for working on smallish pieces using
centrifugal
lost wax casting.
In fact one of the reasons I got interested in induction stemmed from my
interest in micro gas turbines and the wish to cast inconnel turbine
blades.

OH, WOW! This is starting to get very interesting! But, what do you use
for a mold? Investment casting?

Jon