BENDS AND SET-OFFS.
Before you begin bending solid pressed pipes always put the thickest part of your pipe at the back. Lead, in a good plumber's hands, may be twisted into every conceivable shape; but, as in all other trades, there is a right and a wrong way of doing everything, and there are many different methods, each having a right and wrong way, which I shall describe. I shall be pleased if my readers will adopt the style most suitable for their particular kind of work; of course I shall say which is the best for the class of work required.
For small pipes, such as from ½ in. to 1 in. "stout pipe," you may pull them round without trouble or danger; but for larger sizes, say, from 1¼ in. to 2 in., some little care is necessary, even in stout pipes.
Fig. 37 illustrates a badly made bend, and also shows how it comes together at the throat, X, and back, E; L is the enlarged section of X E, looking at the pipe endways. The cause of this contraction is pulling the bend too quickly, and too much at a time, without dressing in the sides at B B as follows: After you have pulled the pipe round until it just begins to flatten, take a soft dresser, or a piece of soft wood, and a hammer, and turn the pipe on its side as at Fig. 37; then strike the bulged part of the pipe from X B toward E, until it appears round like section K. Now pull your pipe round again as before, and keep working it until finished. If you find that it becomes smaller at the bend, take a long bolt and work the throat part out until you have it as required.
FIG. 37.