Hi to all who want to make hollow beads. If you want to make hollow
beads using the casting process using soluble wax,remeber that for
casting , you will need a hole large enough in the bead to support
the investment that will go inside the bead without breaking away in
the casting process. Filigree style beads work extremely well for
this process. What I have done in the past to use soluble wax for the
process is the following. first, I create a smooth solid bead model,
then make a rubber mold of the solid bead... this mold will be used
to inject water soluble wax into the mold . The soluble wax bead
removed from this mold will be used as the inner part to a larger bead
Now, make another bead , solid or with deep detail cut into it and
with 2 opposing sprues attached to this model. The sprues should be
the same size as used in the first model and mold.
Make a mold of this new model... after the mold is made, insert the
water soluble bead that was made from the first mold so that the
sprue is opposing the sprue from your new mold( remember that you new
mold has 2 sprues and this water soluble bead , when inserted will
take up one of those sprue areas in the new mold).
Now inject the mold with regular injection wax... remove this wax
from the mold and put it in warm water to dissolve the water soluble
wax that is inside. To speed this up, cut the water soluble sprue off
first before putting it in hot water.If your regular injection wax
melts at 140 oF , then use 120 of water... you may have to find a way
to keep the water at this temperature long enough to disolve the
water soluble wax that is inside.
When the water soluble wax is dissolve, that hole going into the bead
is where the investment will enter the bead , so remember to tree the
bead with that hole facing up, towards the top of the flask so that
the vacuum will help draw out the air in the bead and replace it with
After casting, remove the investment from inside the bead using high
pressure water blasting , or a thin wire that you can wiggle around
inside to remove the investment . This is a slow process. If your
second bead had deeply cut patterns in it, you will now have a one
piece filigree bead.If it was a smooth bead, you will have a regular
hollow bead with one exit hole..
Something to remember...using this process is 10 times slower than
making 2 bead halves ( models) with location pins so that after
casting they can be easily soldered together as 1 bead.. the 2 bead
halves can be put together in the wax prior to casting so long as you
remeber the first thing that I mentioned in the beginning which is
"you will need a hole large enough in the bead to support the
investment that will go inside the bead without breaking away in the
The reason I say that it is faster to assemble 2 wax halves and cast
them is because the soluble wax method is v veerryyy slow going! we
have made lots of filigree beads as 2 part beads for various
customers and this was the most economical way to do it .
Regular holow beads can be bought from various manufacturers cheaper
than can be cast.They use a forming process to make the beads from
Hope this is helpful.
We do casting, finishing in gold, silver, brass/bronze and pewter for people
in the trade.