Things You'll Need
Casting resin and catalyst
Disposable craft brush
Not all good-looking costume masks are also made well or sturdy. Thin masks made of plastic or soft rubber are in need of a little reinforcing in order to serve as a strong, durable mask to wear for more active events or repeat uses. Reinforce thin plastic with resin and make your mask into a piece of costuming that will last for years to come.
Thoroughly wash and dry the mask. Remove the tie string or elastic and set it aside.
Video of the Day
Lay the mask face-down on a large sheet of waxed paper.
Prepare the casting resin and catalyst according to the directions on the label in a disposable mixing bowl. Make one tablespoon of resin for every three square inches of mask.
Stir the resin thoroughly with a craft stick. Mix it until the mixture starts to look a little cloudy; this means the resin has started to catalyze and will harden properly when used.
Spread the resin on the inside of the mask using a disposable craft brush. Take care when applying near the eye, nose and mouth holes to avoid letting any resin ooze out of the holes and drip down the front of the mask on the other side; apply sparingly in these areas.
Let the resin dry and cure according to the manufacturer's instructions. While the resin is setting from a liquid into a solid state, monitor the mask to make sure the resin isn't pooling more thickly in areas you don't want it to be.
Mix more resin and apply a second coat for more hardening and thickening. If you like, apply a coat to the front of the mask, though bear in mind this will make the mask shiny.