Plumbers' lead work has changed greatly within the last twenty-five years.
In the first place, there is not nearly so much of this work done at the present time, different methods are used for constructing the work, and furthermore, whatever lead work is used on the plumbing system is now nearly all manufactured in such form that it is ready for use without the necessity of being worked up into shape by the plumber. Twenty-five years ago, most of the tanks used on the plumbing system were lined with sheet lead, whereas sheet copper has now quite generally taken its place. Occasionally, however, tanks are required to be lined with lead, and the method of lining with lead is a subject which the plumber should understand, even under the conditions that exist to-day. In the following remarks relative to the lining of a tank with sheet lead, the instructions for laying out the sheet metal itself, apply equally to either lead or copper.
The roll of sheet lead, which should generally be either 4-lb. or 6-lb., should be laid upon the floor, and with the assistance of his helper, the plumber unrolls it, until it lies flat upon the floor. With his dresser the plumber should then go over the sheet lead, taking out all dents, creases, etc. After being thus worked upon, it is ready to be laid out to fit the tank.
In Fig. 19 is shown a perspective view of a tank, the dotted lines showing the lining, each corner being lettered. In Fig. 20 is shown the method of laying out the sheet, whether of lead or copper, for the tank shown in Fig. 19. It will be noted that the lettering of the respective surfaces in the two illustrations correspond. C E F D is laid out the same size as the bottom of the tank. ACDB and E G H F of the same size as the sides, and A C E G and D B H F of the same size as the ends. The measurements F H, E G, A C and B D should be cut about an inch longer than the height of the tank, by the way, in order that this extra length may be turned off and tacked to the upper edges of the tank.
Fig. 19. - Lead or Copper Lining for Tank.
The two sides should be cut about two inches longer than the length of the tank, in order that these strips may be formed around the corners of the tank, to act as a support to the lining, and to prevent the solder from flowing in between the lead and the sides of the tank. These strips should be secured to the ends of the tank with copper nails.
Fig. 20. - Layout of Lead or Copper Lining for Tank.
The dotted lines in Fig. 20 show where the lining is to be bent to fit into the tank. In placing the lead in the tank, it should be folded so as to be easily handled, but with as few sharp bends as possible. After being placed in the tank, the lead sides are gradually worked up into place. The strips left on the corners should be securely fastened, and the corners of the lining driven back into place with a wooden wedge. After the lead has been driven into place, and the small corners on the top edge of the tank filled with a piece of sheet lead, the work is ready for scraping, in preparation for the wiping of the seams. A line should be drawn to establish the width of the joint. Then with the shave hook, proceed to scrape the surface, being careful to make a clean-cut edge and not go over the line. When the scraping has been completed, go over the brightened surfaces with tallow or plumber's wiping flux. The joints or seams are now ready to be wiped.
From 1/2 lb. to 1 lb. of solder should be figured on per foot of seam, according to the size of the tank. On this work a tool known as a plumber's iron is generally used, its purpose being to keep the work heated up. A piece of board should be cut out to fit into the corner at the bottom of the tank, to catch the falling solder. Next take a ladleful of solder in the left hand, and with the splash stick in the right hand, commence to throw the solder onto the seam, shoving it back into place with the splash stick, and taking it from the board at the foot of the seam. Continue this until the work is well tinned, and at the proper heat. When the work has reached this condition, drop the ladle and splash stick, taking the iron in the left hand and the wiping cloth in the right. Pass the iron, which has been previously heated, gently over the surface of the solder, to keep it properly heated, and with the wiping cloth wipe down from the top, a quarter or less of the length of the seam. Do not try to do too much at a time. After getting well started a longer strip can be wiped.
In wiping the seam, the heat is quite likely to cause the sheet lead to leave the wood and rise up, but this can easily be pressed back into place with the cloth.
When near the bottom, plunge the point of the iron into the solder to limber it up, and with the cloth remove the surplus solder. Next remove the board, and finish the joint in the lower corner. While the plumber's iron is generally used, there are some expert plumbers who can wipe a seam without its use. It requires much practice, however, to attain this degree of skill, and, as a rule, the iron is used. The old-style storage tanks were so heavy, especially after the lining had been set in place, that it was difficult to turn the tank over on its side. Therefore the seams were generally wiped upright. At the present time most of the tanks whose seams would have to be wiped upright are tanks used for special purposes, such as acid tanks in factories, etc.
Whenever small tanks are to be lined with lead, the present custom is to turn the tank onto its side and solder the seam with an ordinary soldering copper.
Seams on copper tanks may be wiped or soldered, although, as in the case of lead, such seams are now generally soldered.