ABC OF THE STEEL SQUARE 65 



foot run. Therefore, place the square on 8 and 

 >2 seven times, and you have length and cuts. 



Fig. 35. For the octagon rafter, proceed 

 same as common rafter, only use 13 for run (in 

 place of 12 for common rafter). 



Fig. 35. 



Fig. 36, hip or valley rafter. As these 

 rafters run diagonal with the common rafter 

 ;wnd as the diagonal of 1 foot is practically 17 

 inches, use 17 for run, and proceed same as 

 common rafter. 



HIP 



Length of jacks. If there are to be five, 

 divide the common rafter into six equal parts, 

 use that for a pattern, and it gives the length 

 very nicely. But that will not always work. To 

 get all the different lengths might at first look 

 difficult even to many good mechanics, but it is 



