You have carefully read the instructions and have a clear idea of what
you are about to do. You are going to fill one or more latex moulds
material and then support it so that it retains its correct shape while
it sets. The three steps involved are:
(1) Mixing the casting material
(2) Filling the latex moulds
(3) Supporting the latex moulds while setting.
Take your time and get yourself properly prepared before hand and you
will have no problems.
Mould making at certain times requires you to act quickly due to the
rapid setting times of various products used, so it is a good idea to
prepare carefully by having everything to hand before starting.
Give yourself plenty of room and cover all exposed surfaces with
newspaper. You will need a bowl, preferably of a flexible plastic to do
your mixing, access to water and soap.
For mixing you will need a flat bladed plastic or wood spatula or
stirrer with a long handle. We use a kitchen plastic and rubber bowl
LATEX MOULDS FOR CASTING
Next you need something to support the latex moulds while the casting
setting. We prefer to use rigid cardboard boxes in which we can easily
cut an opening for the mould to fit into. For production pouring,
masonite could be used with the openings cut by jig saw to be more
To find the size hole to cut to support the latex moulds while casting,
moisten the mould base, turn the rim of the mould back and press the
mould against a sheet of paper or cardboard. It will leave a damp
impression of the latex mould base which will enable you to correctly
hole of the correct size into which the mould will sit supported by its
For smaller latex moulds like chess pieces we simply a tall drinking
or a jar of the right size. For large moulds we often turn to buckets
of the right size anything to hold the mould steady and upright during
We will deal with each casting material separately as each has its own
With larger latex moulds that do not have a back-up mould to support
the latex moulds and thus yield a perfect casting, an alternative is to
use the double casting method.
Double casting helps prevent the distortion that results from the
unsupported latex moulds stretching out of shape during casting and
gives a professional casting.
* Make a support
* Fill the mould about one third full of water and pour into a mixing
bowl. Add either the Moulding Powder or the StonePlast whichever you
happen to be using until you have a creamy flowing mixture. It does not
want to be a thin, watery mix.
* Rinse the mould out with water and shake dry. Pour in the mixture you
have just prepared. Squeeze the mould to force the mixture to cover all
the internal surface of the mould. Tilt the mould at different angles
to allow the mixture to flow over the internal surfaces you have just
coated with plaster mixture to keep building up the thickness. Continue
until the mixture ceases to flow.
* Place the mould very carefully into the support so as not to damage
the coating you have built up and allow to set up fully.
* Now fill up the mould fully with a freshly prepared batch of material
being careful not to damage the existing hardened coating.
* When completely set remove the casting from the mould
CLEANING AND CARE
After completing your casting wash the mould before the plaster dries
with soap and water, dry the mould and store in a cool, dry, dark spot
out of sunlight.
If using flexible mixing bowls, it is easier to let the plaster dry and
then by flexing the bowl it breaks easily away from the sides. DO
NOT POUR YOU EXCESS
PLASTER DOWN THE SINK UNDER ANY CIRCUMSTANCES otherwise
you will have a blocked drain. We keep a bucket half filled with water
to rinse our bowls, spatulas while they are in use. The plaster settles
to the bottom and can be disposed of by pouring off the excess water,
letting the plaster at the bottom partially dry and then wrapping it in
newspaper for disposal.
Copyright 2008 Aldax Enterprises Pty Ltd