26 Off-Centre Square to Round

1. Draw a full plan view complete with all element lines and labeling. Choose a line of symmetry to place the seam so you only need to make 1 pattern. Label one half of the plan view, the round end with numbers and the square end with letters.
2. Create a TLD and label it
   
3. Draw a baseline equal to line A-B.
   
4. Pick up the true length of line A-4 and swing it from point A.
5. Next, pick up true length of line B-4 and swing it from point B. Where it crosses the first arc, becomes point 4.
6. Pick up a step-off from the plan view and swing it from point 4. Unlike an on-centre square to round, this fitting needs to be developed one side at a time. Complete one side, then go back to finish the other side.
7. Pick up the true length of line A-3 and swing it from point A.
8. Pick a step-off and swing it from point 3.
9. Pick up the true length of line A-2 and swing it from point A.
10. Pick up a step-off and swing it from 2.
    
11. Pick up the true length of line A-1 and swing it from point A.
12. Pick up the true length of line D-1 and swing it from 1.
13. Pick up line A-D from the plan view (remember that letter to letter is true length) and swing it from point A. Remember that point D should be 90°. If it not, go back and check your work.
    
14. Now, go back to point 4 and work the pattern to the other side, completing it at point C. Notice in this example, line C-7 has no length in the plan view, it is a dot. The true length is the vertical height. Zero plan length put 90 deg to the vertical height, will have no change to the vertical height.
15. Draw in the all the element lines and outside edges, using a flexible curve for the round end.

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