Plaster Molds 



29 



Fig. 25. Molds of large fins should be reinforced with sisal. 



Fig. 26. Left pencil points to a conelike key which has been gouged out 

 of the plaster. The right pencil points to the gouged out area at the base 

 of the fin; it will provide for an extension of the fin when it is cast. Do 

 not remove the fins. Brush sterine over the mold and then apply plaster. 



