PROBLEMS IN PATTERN-MAKING 



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other parts which are on the pattern but not on the casting, 

 their weight must be estimated and deducted from the weight 

 of the pattern. 



WEIGHT OF CASTINGS CAST IN A I-LB. PATTERN 



Questions 



1. Is a pattern made larger than a casting? Why? 



2. What is the allowance for cast iron? Is it the same for each 

 metal? 



3. Describe the steps in working a casting. 



4. What is a pattern-maker's shrink rule? 



5. Must a pattern-maker make allowance for machining a 

 casting? 



6. Is it necessary for a pattern-maker to know machine-shop 

 work? 



7. What is the match? 



8. What is a molding board? 



9. What is a match plate? 



10. Describe a molding machine. State the advantages. 



11. What is the meaning of molding cores? 



12. Is it possible to calculate the weight of a casting from the 

 weight of a pattern? 



