Casts 53 



with a brush. If the mold is intended to be immersed in hot 

 water to facilitate the removal of the wax cast, the wood should 

 be waterproofed with hot wax before securing it in the cast. 



When brushing the wax into the mold, extend the wax over 

 the edge of the hollow impression of the mold and beyond the 

 edges of the fins and tail for about ¥2 inch. This will facilitate 

 removal of the cast from the mold by supplying an area to pry 

 under without damage to the cast. Sometimes, especially if 

 there are undercuts in the plaster mold, the cast will not sepa- 

 rate easilv. In this case, the mold can be warmed just enough 

 to bend the wax slightly, here and there, so that it can be re- 

 moved from the mold without damage. Then, the fish should 

 be pressed back into shape before the wax cools completelv. 



Upon the removal of the cast or positive form from the mold, 

 tiny defects in the surface, usually caused by gas bubbles, may 

 be apparent. The defects and any other blemishes can be cor- 

 rected by filling in these areas with a pastelike mixture which 

 is made in the following manner. Pour a small amount of the 

 wax composition into a glass jar with a screw-type top. Add a 

 few drops of turpentine to the melted wax. This will bring down 

 the melting point of the wax and make it pliable after setting. 

 Place the top on the jar. Shake it well until the wax and the 

 turpentine are mixed. Before using this paste, place the jar in 

 warm water to soften the contents. Use a sculptor's wooden tool, 

 or any other similar device, to apply and model the paste onto 

 the cast. Eventually, the turpentine dries or evaporates; and the 

 repaired area becomes as hard as the rest of the cast. The re- 

 paired areas should have a day or two to dry and harden. 

 Before painting the cast, apply a thin coat of shellac over the 

 entire fish. 



It is not necessary to use the wax composition for repairing 

 if a job must be done in a hurry. Regular putty can be substi- 

 tuted, although the repair job will not be as good. The putty 

 can be colored to match the rest of the cast— if that is desired— 

 by adding pigment (oil color) just as it comes out of the tube. 

 If this makes the putty too sticky, add some whiting or dry 

 plaster of Paris. 



