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of the gas chamber, place a quantity of zinc on the grating. Next replace the hand-hole cover, making sure that it is securely fastened, and screw down tight on its gasket. An amount of water is placed in reservoir A and then a certain amount of vitriol is poured into the water. The wash-bottle J is filled half full of water, and its outlet K is connected to one side N of the branch pipe. The other side of the branch pipe S is joined to the outlet W on the air tank Q. The finger pipe U is connected with
Fig. 34.—Method of Using Oxygen-Illuminating Gas Blow-Pipe Outfit.
the outlet T of the branch pipe. Both cocks S and M are closed. Next take the kink out of the hose connected to outlet E of the gas chamber and allow the air to escape until the charge of water and vitriol runs down from the reservoir into the gas chamber, then slip the free end of this hose over the outlet marked L on the wash-bottle.
As the acid solution acts on the zinc, hydrogen gas is liberated. This gas is not only hot, but is apt to be laden with globules of acid. The function of the water in the wash-bottle is to cool the gas and to clean it before it goes to the finger pipe. Air pressure is pumped up into the tank. The petcock N in the branch pipe is then opened and the hydrogen gas issuing from the burner is ignited. The air is then admitted by opening the petcock S and adjusted until a hot-pointed flame of a greenish color is obtained that is suitable for burning. If any of the solution is spilled its
Fig. 35.—Showing Antimony-Lead Alloy Grids Before Filling and How
Plates are Joined Together by Connecting Straps.
action may be neutralized by using Gold Dust, Pearline, washing soda, slaked lime, or ammonia. If burned when pouring acid into the reservoir, which, of course, will not occur unless this is carelessly done, apply olive oil to the burn and not water.
Another outfit suitable for lead burning consists of apparatus for burning a mixture of oxygen and illuminating gases. As oxygen is widely used in many garages for carbon removal, the same tank may be easily connected up to a single blow-pipe outfit. The connections are very clearly shown at Fig. 34. As the oxygen is carried under very high pressure in the tank it is necessary to provide a pressure reducer so that its pressure will not be too high at the burner. The illuminating gas is turned on first and ignited, after which the oxygen supply is regulated, so that a good-burning flame is secured.
Lead Burning.–Lead burning consists in melting the metals and causing the parts to flow together and become joined without the aid of solder. It requires considerably more skill than any other form of brazing or soldering. A long step toward success may be taken by the proper arrangement of the work. It is usual to provide something which may serve as a mould or guide for the melted metal. For example, if two lead sheets are to be united by soldering, they are laid on a sheet of some non-heat-conducting substance, such as brick or asbestos. The work in the immediate neighborhood of the joint is carefully scraped so as to remove all oxide or scale which would tend to bind the melted lead and prevent it from flowing freely. The metal at the seam is heated by a very hot bit or the flame from a blowpipe, so that there is a uniform flow of lead across the seam. It is sometimes necessary to add more lead to the seam by melting a strip held in the hand. A flame of some sort is the most satisfactory source of heat for the average lead-burning job, because not only is the heat more uniform, but also more intense, and the lead melts at the desired point before the surrounding metal becomes sufficiently hot to soften. There are several types of blowpipe for this purpose on the market. The flame is usually small, sharp-pointed, and very intense. Lead burning is absolutely necessary, and is insisted upon in certain classes of work, for instance, in lining tanks, with lead for chemical solutions, or for joining the grids and lugs of storage batteries.
Directions for Lead Burning: To connect the various plates comprising an element, the Gould Storage Battery Company advise the use of a special fixture to insure accuracy in spacing. Be careful to select the proper spacer (Fig. 36), and attach it to the burning-rack. Place the plates on the burning-rack so that the lugs extend through the slots in the spacer. Fit the connecting strap over the lugs. Adjust the spacer by the adjusting nuts until the strap is at the proper height on the lugs. Using the flame, melt the lug to be burned and the adjoining material until they tend to run together. Using a piece of burning strip, melt the end thereof and fill in around the lug until the whole is a molten mass. Allow the joint to cool and cut off the protruding end of the lug with a pair of end-cutting pliers. Melt the remaining end of the lug till it flows into the strap. Repeat until all plates are burned to the strap.
Burning Plates to Old Straps: The storage battery company
Fig. 36.-Gould Burning-Rack for Supporting Plates When Burning
Plate Lugs to Busbars.
furnishes connector straps for nearly all the modern types of batteries. Sometimes it happens, however, that a battery of an old model or of a manufacture seldom used will be set up with straps that cannot be duplicated. Under these circumstances the old straps should be utilized. With the hacksaw cut off the plates.
Cut slots in the strap, using the old lugs as a guide. Cleanse the strap thoroughly in ammoniated water and scrape clean. Using the proper spacer, proceed as described above.
To Burn Terminal Connector to Pillar Post: Scrape the parts clean. Fit the terminal connector to the pillar post. If the terminal connector does not set low enough, ream the terminal with the triangular scraper until the fit is exact. Heat with flame until the inside of terminal connector and outside of pillar post are one molten mass—throughout. Fill in with molten, burning material and allow to cool. To burn connecting link to pillar posts, proceed as above.