Ellsworth M. Longfield

“ The experienced draftsman always takes advantage of this fact when a whole pattern is to be developed. The line D-1 in Fig. 283 is next drawn, and when a distance is laid off from point A a like distance is also laid off from point D. With point A as a center and a radius equal to the hypotenuse of triangle A-2 an arc is drawn bearing away from point 1. This is intersected by an arc drawn from point 1 with a radius equal to the distance 1-2 of Fig. ”

“ Transition between a Square Pipe and the Second Piece of an Elbow.—In order to save height the sheet metal draftsman is often compelled to design a transition between a square or a rectangular pipe and the second piece of a round pipe elbow. In other words, the transition takes the place of the first piece of the elbow. ”