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Mouldy Techno Tips This basic mould making strategy is
== ——_ versatile and flexible, With a coping saw

and an ample supply of masonite or plastic
sheeting one could invent endless new
forms,

Diligent readers may remember an account
of Andy Martin's workshop that appeared in
the April 95 issue of the newsletter. Im that
article | described the construction of a
mould fer solid casting forms with hollow
foot rings. Thar trick, however, is one he
doesn't use often. He depends on the
strategy that this article deseribes more
frequently.

Pat Taddy

Mest of che vessels char Andy makes have
bases and top openings that are determined
by the shapes of masonite patterns. If a
flange is required a chird pattern, with an
edge, is set back from the top pattern edge
by the expected wall thickness af the cast
object.

Alsec avsmmnbl, al hae
Space betweer a»

etberns kus heer

Tlustranon 1 shows how the top and
bottom patterns are assembled in the first

stage of the construction of a solid model. Fi stubbed ath elow, eobval,
The sticks separating the two pieces of a : way then trimmed mt
masonite will determine the height of che Ae &- a foal similar te
form. These patterns can be recycled for

another form such as a lid, through Pi

adjustments to the length of the separating

sticks. Once this object has been cobbled

together, clay is stuffed inte the space

between the patterns (2), and any excess is

trimmed away with the aid of a large wire @

bow (3).

In che case of the form in illustration 2, the
first section of the mould can be poured in
one piece, since the taper from che large top
to the smaller base of the model will ensure

that a cast piece releases easily from the . ( =

mould. Andy will sometimes, if the model © ) =P .

has two vertical sides, pour two mould 3 # olay . been
sections for che walls. Once this or these £ wacd or exasenita patra

have set, soap or a spray acrylic is applied to
any plaster surfaces thar will be in contact
with section B of che mould when it is
poured. He avoids using Vaseline since it
may permanently interfere with water ;
transfer inte che mould, is :

The cwe pieces completed ac this srage may
be used to cast an open, flat bottomed bowl,
bur to allow the mould to be used for a

Cronus eection af mauld oem

lidded form as well, Andy will seack a piece OU Ed asd it xckenbicd: ages "
of thicker plywood or masonite (1/2" to | rf fame set, of. 3 sie re
/4") on Cop af the solid model before me alates ip cab

pouring section C (see illustration 5), This
thicker pattem is the same shape as the one
it sits on, but is amaller to allow a sill to be
formed where the flamge meets the pot
walls,