Hi Lorri, I bought my Delft Clay system at a local supplier here
in Sweden but I’ve seen it in The Rio Grande catalogue as well.
The whole system consists of two aluminium rings (approx. 6 cm in
diameter 2.5") each 2,5 - 3 cm high (1"). The clay is a red dry
very fine grain sort of casting sand. The procedure is similar to
sand casting but it is really easier to get a good quality
casting out of it.
It’s easy - you turn the bottom ring up side down - stuff clay
into it and pack it by pounding with a hammer (not too hard
though) - remove excessive clay from the bottom bu pulling a
metal ruler over the ring. Turn the ring right side up and the
you press your master object (no undercuts) half-way into the
sand - you can then add chunks of sand if necessary to make sure
that there is no under-cuts for the other half.
Now you powder with talk and apply an even talk layer with a soft
brush. Add the upper ring (there are index marks to align the two
parts) and stuff the upper ring with clay and pound with hammer
and remove excess with the ruler.
Next step is to separate the two rings from each other and remove
your object. Then cut the sprue (pouring hole) - if I fail
somewhere in the process - this is the time. You have to be very
careful when you cut the pouring hole as it is very easy to
damage the form you’ve impressed.
Don’t forget to make vent holes as well - the position of these
are are or less obvious when you see it.
Now just put the two rings together using the index marks for
alignment - melt the metal in a cubicle and pour when you’ve
reached the proper temperature (silver looks like mercury and
with a mirror surface) - Do not pour to early - the mould is not
hot and the metal will get stiff before filling completely.
Chill the whole thing in cold water and separate the rings from
each other and remove your cast cut the sprue and vents and
The clay is reusable - you just have to remove the burnt parts
(the clay that had contact with the hot metal). One bag of clay
(approx. 1 kg) will be enough for about 90 castings.
The neat thing is that if you make a mistake - you just do it
again - nothing lost in the process…
It is really simple but I recommend that you get the video tape
(usually included in the complete set) and then you just imitate.
I’ve made approx. 30 castings and failed approx. 5 - because I
forgot to vent properly or poured before the metal was at the
One complete cast is perhaps 5 - 10 minutes (non experienced) so
it’s quick to test…