All content copyright Opus Studio 2013
CASTING TECHNIQUES
Materials and techniques used in our production methods.
This section of our site explains in more detail some of the materials and techniques used to produce
our work.
Resins and composite materials have become some of the most versatile media in the world of art
and design, as well as being extremely important in a huge range of other industries. We use a
multitude of composite materials, including specialist resins, aggregates and various fine metal
powders. Surfaces can be treated with various patinating fluids, paints, stains and lacquers to
achieve a dazzling array of effects.
We make all our moulds in house, and their design is individually tailored
to suit the type of work, and the customer's requirements. We use a
number of different silicone rubbers, both addition and condensation cure
and we can advise which type of silicone is most suited to the
application. We can also provide information on expected mould life and
give professional advice on any other queries the customer may have.
We are also able to build quality GRP or composite moulds, particularly
suited to smooth, geometric shapes.
Site Design by Fingertips
Moulded from a stone surface.
Cast using copper, iron and
crushed terracotta, then
oxidised.
Hare, created in copper resin.
Dramatic sculpture cast in Iron
resin then oxidised, patinated
and partially polished.
(click to see more)
Applied Sandstone
Standard Resin Casting
Our castings are generally made with filled polyester resin. Various types
of filler powders are used depending on the finish required.
These are mixed with the resin in accurate proportions and the mixture is
then poured into the mould under vacuum. This process removes the air
trapped inside the mould and mixture to produce perfect castings.
Metal finishes including Bronze, Aluminium, Copper and Iron are
achieved by mixing metal powders with the resin. This is known as "cold
casting". A convincing, quality finish is achieved by ensuring the highest
possible ratio of metal to resin. As a result the surface of the casting is in
effect a real metal surface. It will age in time, and react to conditions, in
the same way as solid metal. (and usually at a fraction of the price).
As with traditional metal casting, surfaces can be treated to achieve
different finishes. These vary from highly polished surfaces, to a heavily
oxidised, or patinated finish.
Finishes can also of course be partially or completely post-applied. We
work with a wide range of paints, stains, waxes, and gilding materials to
create any kind of effect that is required by the customer.
See our own bespoke curtain pole range for many examples of painted
and stained items.
Clear Resin Casting
We have done exhaustive research into using clear resins and, as
anyone with similar experience will tell you, it is something of a dark art!
We have mastered several techniques for using clear resins successfully
and have drawn on this knowledge extensively for our own range of
Contemporary Tiles. Depending on the application we use either clear
polyester, polyurethane or epoxy resin.
There are different ways of treating the surfaces of these castings, which
will achieve different finishes. Varying from highly polished crystal clear
glass, to an ocean eroded appearance. We can also change the levels of
translucency and colour.
Clear casting of a shoe last
used in window displays.
Cast in clear resin and finished
in multicoloured lacquers.
Composites
Cast resin has limited physical strength. Therefore larger and more
delicately shaped objects need to be reinforced. This can normally be
achieved using chopped strand glass with polyester resin (GRP).
We are also able to produce more high-tech composites. Using epoxy
resin and woven fabrics including glass fibre, carbon fibre and Kevlar.
These types of composites can be engineered to very specific
parameters of weight and strength, as necessary. This technology has
been developed in the world of racing yachts and Formula One. These
are very much design-orientated sports, and a little of this designer feel
has helped to increase the appeal of such materials in other areas.
Carbon Fibre reinforcement
can be incorporated inside
the finished piece for high
structural strength.
High-tech performance
resins using Kevlar and other
composites and used for
demanding applications
including Polar expeditions.
Foam Carving and Skinning:
This technique is ideal for achieving large, structurally strong shapes,
relatively quickly.
The shape is carved in polystyrene foam, and then "skinned" using
epoxy resin and woven glass fabric. Most finishes can then be applied.
Shapes made in this way are suitable either as a one-off saleable piece,
or may be used as a master for moulding.
Check out our News section
for the latest stories.
Vacuum chamber for removal
of trapped air bubbles in casts.
Opus Studio
Bramble Farm
Ham Lane
Kingston Seymour
Clevedon
Bristol BS21 6XN
Tel/Fax: 01934 835 739
Oxidised Iron Resin
This larger-than-life casting of a sculpture of a horse skull illustrates the level to which resin can
imitate the finish of oxidised metals, in this case iron.
After de-moulding and careful preparation
with chemical patinating fluids, the casting is
weathered in natural daylight.
Detail of the finished sculpture. The transformation of
the surface creates a finish that is practically
indistinguishable from genuine iron.
Foam Carved Mosaic Sculpture
This large exterior sculpture, at the entrance of
a primary school, illustrates a versatile
technique which can be used to produce large
and strong structural shapes, relatively quickly.
The design is first carved in polystyrene foam,
and then "skinned" using epoxy resins and
woven glass fabric. Almost any finish can then
be applied, in this case coloured mosaic tiles.
Discovery - Memorial to Francis Crick
Another example of large scale foam carving.
This piece titled ‘Discovery’ is on display in
Northampton, the birthplace of Francis Crick who,
with his colleague James Watson, first identified
the ‘double helix’ structure of DNA.
(The actual figures are life-sized)