_Fifth_, rasp the edges of one end as shown in the cut. Hold the work in such a way that the stroke of the rasp can be seen without moving the pipe.
_Sixth_, take the other 6-inch piece of pipe and with the TURN PIN spread one end of it. The turn pin must be struck squarely in the center with the HAMMER, the point of the turn pin being kept in the center of the pipe. The pipe should be turned after each blow of the hammer. The pipe must not rest on the bench but should be held in the hand while using the turn pin. If the pipe bends, it can be straightened with BENDING IRONS. If the pipe is spread more on one side than the other, the turn pin should be hit on the opposite side so as to even the spread.
[Illustration: FIG. 15.]
_Seventh_, when the pipes are properly fitted, moisten the tips of the fingers with paste and rub the paste on parts of pipe marked "paste." Put the pipe aside to allow the paste to dry.
_Eighth_, put the soldering iron on to heat.
_Ninth_, with the SHAVE HOOK scrape off the paste and surface dirt as shown in the figure. The inside of the cup will look bright, but must be scraped.
[Illustration: FIG. 16.--Cup joint.]
_Tenth_, place the two pieces into position as shown in Fig. 16, sprinkle rosin on the joint, melt a few drops of solder on the joint and with the iron melt the solder on the joint, drawing the iron around the pipe keeping the solder melted around the iron all the time.
_Eleventh_, fill the joint with solder and continue to draw the hot iron around the joint until a smooth and bright surface is obtained. To master the correct use of the soldering iron in this work, considerable practice will be necessary.
OVERCAST JOINTS.--(Fig. 17.)
NOTE.--Each operation must be performed thoroughly.
_First_, saw off from a coil of 1-1/2-inch D lead pipe a 10-inch piece of pipe.
_Second_, square the ends with the rasp, as previously explained.
_Third_, take a 1-1/2-inch DRIFT PLUG and drive through the pipe (Fig. 18).
_Fourth_, saw the pipe into two pieces of 5 inches each.
_Fifth_, square the ends of the pipe with the rasp.
_Sixth_, rasp off the outside edge of one end of the pipe as shown.
_Seventh_, rasp off the inside edge of one end of the pipe.
_Eighth_, finish rasped surfaces with a file. Both surfaces should have the same angle.
[Illustration: FIG. 17.]
[Illustration: FIG. 18.]
[Illustration: FIG. 19.--Overcast joint.]
_Ninth_, with a shave hook scrape the outside surface of each pipe for about 1 inch from the end.
_Tenth_, put the soldering iron on to heat.
_Eleventh_, paste paper on the joint as shown in the cut.
_Twelfth_, fit the pieces together and lay on the bench. Drop some melted solder on the joint and with the hot iron proceed to flow the solder around the joint by turning the pipe. Use plenty of flux (rosin). The pipes must be tacked in three or four places at first or they will have a tendency to spread.
_Thirteenth_, to finish the joint, lift the iron straight up.
This joint when finished will have a bright smooth finish. The two foregoing joints need considerable practice and should be perfectly mastered before going on to the next job.
SEAMS
A description of the making of wiped seams for lead-lined tanks will not be attempted as very few are made now. The plumber, however, is often called upon to make a seam joining two pieces of sheet lead. The beginner will do well to go over the following exercise carefully and practice it thoroughly.
[Illustration: FIG. 20.--Flat seam.]
MATERIALS.--Two pieces of 8-pound sheet lead, 6 by 10 inches each; one bar of 1/2 and 1/2 solder; paste, paper, and rosin.
TOOLS.--Rasp, shave hook, and soldering iron.
The 10-inch side of each piece is rasped and fitted together. The edges are cleaned and paper is pasted on leaving 1/4 inch for solder. Paste without the paper can be put on. This will make a joint 1/2 inch wide.
Apply the rosin to the joint, then with the heated iron and some solder tack the seam on the top, then on the bottom and middle.
This will prevent the seam from spreading when the lead is heated.
Solder and rosin can now be put on the full length of the joint.
With a hot iron proceed to float the solder down the seam. The soldering iron must not rest at full length on the pieces of lead or it will melt the lead and render the work useless. The solder will flow and form a clean neat seam, if the iron is at the right heat and the right amount of solder is put on. If the iron is too hot, the solder will flow instantly when the iron is laid on it and the solder will disappear as it runs through the seam. If the iron is too cold the solder will not melt enough to flow. Too much solder on the seam will cause it to overflow, that is, the solder will spread beyond the papered edges. After a little practice this surplus solder can be drawn in on the seam with the iron and carried along the seam to some point that has not enough solder.
When the seam is completed the edges should be perfectly straight and even. The iron is carried along the seam with one stroke which makes the seam appear smooth and bright.
CHAPTER III
MIXTURES OF SOLDERS FOR SOLDERING IRON AND WIPING. CARE OF SOLDERS.
MELTING POINTS OF METALS AND ALLOYS
The importance of good solder, that is, solder correctly mixed and thoroughly cleaned, should not be overlooked. Work is more quickly and neatly done and the job presents a more finished appearance when solder that is correctly made is used.
The solder used in the following work with the soldering iron is called 1/2 and 1/2. This means 1/2 (50 per cent.) lead and 1/2 (50 per cent.) tin.
In the mixture of solder, only pure metals should be used. The lead should be melted first and all the dross cleaned off. The tin should then be added and mixed.
The solder to be used in wiping the joints in the following chapter is a mixture of 37 per cent. tin and 63 per cent. lead. This is called wiping solder.
The following table gives the melting points, etc.:
---------------+---------+------------------------------------------ Melting Metal point Mixture ---------------+---------+------------------------------------------ Sulphur 228 Pure Tin 446 Pure Lead 626 Pure Zinc 680 Pure Fine solder 400 50 per cent. tin, 50 per cent. lead (wt.) Wiping solder 370 37 per cent. tin, 63 per cent. lead (wt.) ---------------+---------+------------------------------------------
To recognize fine solder, run off a bar into a mold and let it cool. If there is a frosted streak in the center, the metal has not enough tin. The surface should be bright. To recognize wiping solder, pour some on a brick. When this is cool, the top should be frosty and the under side should have four or five bright spots.
The amount poured on the brick should be about the size of a half dollar. If poured on iron, the metal will cool too quickly and show bright all over the under side.
TO MAKE 1/2 AND 1/2 SOLDER OR PLUMBER'S FINE SOLDER.--The possibility of getting pure clean metals to mix solder is very remote. Old pieces of lead pipe, lead trap, old block tin pipe are used to make solder when pure metals are not at hand.