The materials necessary to complete this job are as follows: 12 inches of 5⁄8-inch extra strong lead pipe for the run; 6 inches of 1⁄2-inch extra strong lead pipe for the branch; paste and paper, and solder.
Fig. 30. - Branch joint.
The preparation of this joint requires the skill of the beginner more than any of the preceding joints. The tapping of the 5⁄8 pipe for the branch connection, pasting and cutting the paper, require the utmost care and precision. The 5⁄8-inch pipe is tapped with the tap borer in the center. The tap borer is used by grasping the handle firmly and putting the cutting point on the mark and then pressing down on the handle. This forces the point into the lead. Now turn the tool and a piece of lead will be bored out. Continue this operation and a hole will very soon appear in the lead. A hole just large enough to allow the bending irons to enter is made. The opening of the hole is completed with the bending iron, working the lead back slowly into place. Do not attempt to drive the lead back around the hole with a few strokes. One bending iron is inserted and this iron is struck with another iron or hammer. After a number of strokes the opening will be of sufficient size. The bent end of iron is inserted into the hole and the bent part enters the bore of the pipe. This iron is struck in such a way as to force the lead around the hole up, rather than back. Now with the straight end of irons open the sides. When the wall of pipe has been driven up a little the hole can be enlarged by driving back the lead. This procedure will form a collar around the hole to steady the branch pipe. Good workmanship will result in having a good substantial collar around the opening. The branch should now be fitted. Clean the pipe with the shave hook for about 2 inches on each side of the opening. With compasses set at 11⁄8 inches, mark off a space on each side of the branch on the run, or on the 5⁄8-inch pipe. On the sides of the pipe the two lines should be joined with an even and symmetrical curve. A good way to make this curve is with the shave hook. Now take a folded piece of paper and cut out the shape of one-half of the joint, then open the fold and the entire ellipse will be made. When this paper is cut, a sharp knife is used, otherwise a ragged edge will be made and a good finish of joint is impossible. The paper is now pasted and put on the pipe. The surplus paste on the edge of the paper should be wiped off with the fingers before the paper is put on the pipe. This prevents any paste squeezing out on the joint. The branch is now taken and perfectly fitted into the run. The end is cleaned with the shave hook and paper is pasted on the pipe, leaving 11⁄8 inches of cleaned surface for wiping. The paste and the paper should now be allowed to dry. The position for wiping this joint is to have the run horizontal and the branch on an angle of 45° pointing away from the wiper. Figure 30 will bring out the above explanation very vividly.
The run of this joint is laid flat on the table and the branch inserted in its proper place. With one hand hold it in place, with the other, use the bending iron, tap the collar on the run against the branch, wedging it in place good and strong so that no solder can leak through. If the branch is tapered with the rasp as shown the joint can be made very tight. The run of the pipe is now laid on two bricks as was done with the horizontal joint. The branch is laid over on a pile of bricks or wood at an angle of 45°. The best way to secure this joint is to pour some half-molten solder on the ends of pipe and brick, making a solder clamp. This branch does not need any clamp or weight if it is properly entered into the run. A strap of solder can be run over the end of pipe if found necessary. Place the catch pan under the joint and then the pipe will be ready to wipe.
In wiping this joint, the catch cloth is used not only to catch the solder as it drops off from the pipe, but also to hold the hot solder against the pipe to heat the under side of the joint. Test the solder and see if it is the correct heat for wiping. If so, prepare for wiping. After heating the ladle, take some solder in it and proceed to drop the molten solder on the joint. The ladle is moved constantly as the solder is dropped on the run and then on the branch to get the entire joint to the proper heat. As the solder drops off from the joint, it is caught on the catch cloth and brought up on the top of the joint where it is re-melted by dropping hot solder on it. Then the hot solder is held in the cloth against the under side of the joint to get the under side properly heated. The solder is worked around all parts of the joint. When the heat is got up sufficiently and the solder works freely around the joint, the branch cloth is taken and each edge of the joint is wiped clean. Any surplus solder is brought up on top of the joint and then wiped on the catch cloth. This solder is then put on the under side of the joint. With the branch cloth reach way around the joint and wipe each side, bringing the cloth each time to the top and then off the joint. The last wipe is directly across the top, wiping off any surplus solder that may have accumulated from wiping the sides. The difficulty with this joint is in getting the top and bottom to have an equal amount of solder. With a little practice and by watching each motion your faults can be noted and remedied. If the paper starts to come off, it should be re-papered at once. When the joint is finished, it should be left in position until the solder has had time to set and cool, otherwise the branch will break off and considerable time will be lost in correcting the trouble.