When putting ends on tubes and cylinders you can make a circular lap seam as shown at [I], or a circular folded seam as at [J] or a circular overfolded seam as shown at [K].
How to Solder Metals.
—The great secret in soldering metals is to have them perfectly clean and then if you use the right kind of flux and the proper solder you will not have any trouble.
Fluxes.
—After you have cleaned the surfaces to be soldered you must use a flux to prevent the metal from oxidizing and to make the solder stick. Different metals require fluxes of different kinds.
When soldering bright new tinware use powdered resin for the flux, but if the parts are old then scrape and clean them well and use a flux of zinc chloride solution. To make it dissolve 5 cents’ worth of zinc chloride—which is muriate of zinc—in a small clean inkbottle full of warm water; or you can make the muriate of zinc by dissolving some zinc clippings in muriatic acid and to make the soldering fluid add some water to it.
This kind of a soldering fluid is a good flux for tin, iron, steel, brass and copper. It is good for all ordinary work but it must be washed off from iron or steel as it will rust them very quickly. To solder copper sal ammoniac can be used.
The only kind of a flux to solder zinc with is a solution made of 10 per cent. of muriatic acid and 90 per cent. of water. For lead, pewter and any alloy with lead in it use tallow, Gallipoli oil or Venice turpentine. Resin can be used successfully for all metals provided they are scraped bright and clean before they are soldered.
Solders.
—Just as certain metals require given fluxes so also do these metals need special solders.