PATTERN MAKING 



55 



Fig. 104. 



METHODS OF MOULDING. 



As has already been said, it is necessary that the patternmaker 

 should have some knowledge of moulding in order that he may 

 construct his patterns so that they can easily be removed irom 

 the sand. A brief description of the general method employed wal 

 suffice. 



Ordinarily, a casting is made in a flask consisting of two 

 parts, each containing its complement of sand. The upper part is 

 called the cope, and the lower part the nowell or drag. The 

 pattern is sometimes made in two pieces that part along the line 

 separating the cope and the drag. Thus in Fig. 105 the pattern 

 separates with the flask, on the line A B ; and when so separated, 

 the cope is turned upside .down and the portion of the pattern C is 

 lifted out. The part D is lifted out of the drag in the same way. 



