Fibreglass is a lightweight, strong material used in a number of industrial and artistic projects. If you need to make masks for a prop or fancy dress costume, fibreglass is an ideal construction material. By first sculpting the mask and making a mould of the sculpture, you can create dozens of identical masks. All of the materials required are available at your local art and hardware shops.
Sculpt the mask out of modelling clay. You can freeform it, but you will get much better results working on a pre-existing mask, face form or large polystyrene head.
Seal the finished sculpture with two thin coats of acrylic enamel spray.
Brush a thin coat of latex moulding rubber over the entire sculpture, extending it slightly past the edges.
Allow the latex to dry. If desired, you can speed this process with a hair dryer.
Brush on an additional nine coats of latex, letting each coat dry before moving on to the next.
Cut a piece of cheesecloth into several 7.5 cm (3 inch) squares.
Brush on another layer of latex, then press squares of cheesecloth into the wet latex until the entire mould is covered.
Continue adding latex and cheesecloth until another four layers are complete. Allow the latex to dry.
Cover the latex mould with five layers of plaster bandages. Dip each bandage in water to activate it before smoothing it on to the mould. This will form a support shell and help the latex mould to keep its shape. Allow the shell to completely harden.
Remove the shell from the latex mould, then clean the clay out of the mould. Return the mould to the shell once all of the clay is gone.
Place the mould in a cardboard box filled with packing foam for support.
Spray a coat of mould release, available at industrial suppliers, into the mould. Allow it to dry and blot out any excess with a paper towel.
Mix a batch of fibreglass gelcoat and resin in a disposable bucket, follow the mixing ratio on the gelcoat container carefully.
Use a cheap paint brush to brush a thin layer of catalysed gelcoat into the mould. This will form the smooth outer surface of the mask. Allow the gelcoat to harden.
Cut fibreglass mat into several 10 cm (4 inch) squares.
Mix a batch of fibreglass resin and catalyst in a disposable bucket.
Brush a layer of catalysed resin onto the hardened gelcoat, then press squares of fibreglass mat into the resin. Completely cover the gelcoat, overlapping the squares slightly to ensure there are no missed areas.
Brush more resin onto the fibreglass, saturating it fully. Work out any trapped air bubbles with the bristles of the brush.
Apply two additional layers of resin and fibreglass squares.
Let the finished mask harden overnight.
Remove the mask from the mould and use a rotary tool to trim out the eye holes and clean up any rough edges.
Paint the mask as desired.
Line the inside of the mask with felt, held in place with hot glue or spray adhesive, to protect your skin.
It is important to keep the layers of latex thin. If they are too thick, an outer skin will form and prevent the latex beneath from drying.
Wear rubber gloves, a dust mask and eye protection when working with fibreglass.