140 



Popular Science Monthly 



When the intersections of these lines have 

 been marked with a cross, connect the 

 lines with straight lines and the pattern 

 will be complete. Make allowances for 

 seams and laps. 



To develop the pattern for the large 



In the working out of this problem 

 two additional steps are taken 



pipe proceed in the same manner as de- 

 scribed in the last article. First draw 

 the lines G — H and K — L, obtaining the 

 correct length by transferring the dis- 

 tances from the points on the end view 

 as was done in the problems in the pre- 

 vious article; then run the lines up from 

 the joint on the front view. Where the 

 same numbered lines intersect, make a 

 cross. 



Now we come to the first new step 

 required by this problem. No diiiiculty 

 will be found with the lines 3 and 4, as it 

 will be seen from the end view that lines 

 4 and 2 of the small pipe rest on them, 

 but when you come up with lines 3 and 1 

 from the front view you will find that you 

 have no place for them. By looking at 

 the end view of the large pipe it will be 

 noticed that lines 1 and 3 of the small 

 pipe meet the large pipe exactly midway 

 between 3 and 4 on the pattern. The 

 point where the lines 1 and 3 from the 

 front view cross this line marks the loca- 

 tion you are trying to find, as shown in 

 the drawing. 



The second problem. Fig. 2, is worked 

 out in a similar manner, but is made a 

 little more complicated by the fact that it 

 requires more extra lines to locate the 

 pattern for the hole in the large pipe. 



Briefly, the steps to be taken are: Draw 

 front view A, end view B; complete the 

 front view A by drawing the joint. Do 

 this in the manner described in Fig. 1, 

 this being one of the two new steps men- 

 tioned in the first paragraph; develop the 

 pattern for the small pipe, in the manner 

 already described, drawing the base line 

 E — i and obtaining the correct length by 

 transferring the distance from the bottom 

 view; run the lines upward from the base 

 line, and the lines over from the joint line, 

 and where the same numbered lines inter- 

 sect make a cross to indicate the pattern 

 line. 



To develop the pattern for the large 

 pipe, draw the line G — H and K — L, 

 obtaining the correct length by trans- 

 ferring the spaces from the end view. 



Now we come to another of the new 

 steps in these problems. By looking 

 at the end view you will notice that the 

 hole in the large pipe will be between 

 numbers 4 and 6, and that the hole does 

 not rest exactly on the numbers. We 

 also see that number 7 of the small pipe 

 coming up from the bottom view meets 

 the large pipe a short distance away from 

 number 6. With the dividers, measure 

 that distance and transfer it to the 

 pattern as indicated by lines 6 and 7 



A little different application of one of 

 the new stepS is shown in this problem 



on the pattern. Lines 8 and 6 with 2 and 

 4 are a short distance away from 5 of 

 the large pipe. Mark the distance on 

 the pattern and number the lines with 

 the same numbers as the spaces on the 

 small pipe. Then from the front view 



