Rule 1. Always wax the big jobs such as large dragons, in the summer, its a hell of a lot easier !
Rule 2. If you ' have ' to roll tiny lengths of wax such as spines or teeth in the heat, putting the wax in the fridge for a couple of minutes prevents it from continuously smearing.
Rule 3. One error casting and you are liable to have molten metal clawing at delicate parts of your anatomy.
Rule 4. Expect blisters !
It all begins with an idea and a block of black wax from my local foundry. The wax is extremely malleable, the heat from my fingers is enough to bring it to a workable consistency.
On a cool or cold day, I have a extending lamp at my shoulder which is enough to warm the wax sufficiently. Using a variety of probes,dental tools, a small flame and my fingers [ here's hoping I never get arthritis ! ] I shape and mould the wax to a fully formed model.
If it is a dragon I cut up the wings and the body ( which are almost always long ) into castable pieces.
Preparing a wax for casting can range from an hour ( a moulded work ) to 200 hours for a one-off big dragon.
I make all the masters myself and form a silicon rubber mould around the master from [ sadly ] discarded wine casks.
The master wax is attached to the cardboard base by the sprue which is a short wax tube about the thickness of a cigarette, that will eventually form the channel that the molten metal will pour through into the waiting cavity.
I then construct cardboard walls around the wax, a little higher than the wax mould and seal all the cracks with packing tape, forming a container into which I pour silicon rubber that completely encloses the wax.
After curing for 24 hours, the now very flexible rubber is ready to be carefully sliced open with a extremely sharp blade.
I have to remember where the small cross sectioned pieces, such as legs were, in order to extract them in the most efficient way possible. This has to be done because there may be hundreds of future waxes coming from the mould and although none come out undamaged, it is desirable that the least damage possible is achieved.
I always have a certain amount of repairing to do and I use a varity of tools to regain the standards that I achieved when the master was made.
The wax is then attached to a round rubber base that has a raised section in the center with a hole the size of the sprue. I build up the sprue a little around the raised section to seal all gaps, weigh the wax and the base and do certain calculations to obtain the exact amount of bronze required for a successful cast.
I then place into the base, which has slightly raised walls a steel flask about 3" in diameter and about an inch higher than the wax. This encloses the wax, not touching it. This forms a seal that, again with packing tape I reinforce to prevent any leakage of the next stage, that of investing the wax.
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