Part 16 (1/2)

CHAPTER VIII

SOLDERING, BRAZING AND THERMIT WELDING

SOLDERING

Common solder is an alloy of one-half lead with one-half tin, and is called ”half and half” Hard solder is made with two-thirds tin and one-third lead These alloys, when heated, are used to join surfaces of the saalvanized iron, zinc, tinned plate, etc These metals are easily joined, but the action of solder with iron, steel and alureater care and skill

The solder is caused to make a perfect union with the surfaces treated with the help of heat fro iron is made from a piece of copper, pointed at one end and with the other end attached to an iron rod and wooden handle A flux is used to remove impurities from the joint and allow the solder to secure a firm union with the metal surface

The iron, and in asoline blow torch, a sas furnace, an electric heater or an acetylene and air torch

The gasoline torch which is asoline through the hole in the botto the small hand pump for 10 to 20 strokes, hold the pale iron tube on top of the torch and open the gasoline needle valve about a half turn Hold the torch so that the liquid runs down into the cup below the tube and fills it Shut the gasoline needle valve, wipe the hands dry, and set fire to the fuel in the cup Just as the gasoline fire goes out, open the gasoline needle valve about a half turn and hold a lighted nite the asoline and air Open or close the needle valve to secure a fla

On top of the iron tube fro the soldering iron with the copper part in the flame Place the iron in the flame and allow it to remain until the copper becomes very hot, not quite red, but al iron or one that has beenTo do this, take the iron from the fire while very hot and rub the tip on so acid Then rub the tip of the iron on a stick of solder or rub the solder on the iron If the solderthe end of the iron, allow a few drops to fall on a piece of tin plate, then nil the end of the iron on the tin plate with considerable force Alternately rub the iron on the solder and dip into flux until the tip has a coating of bright solder for about half an inch from the end If the iron is in very bad shape, itin the flux for the first time

After the end of the iron is tinned in this way, replace it on the rest of the torch so that the tinned point is not directly in the fla the flame down to accomplish this

_Flux_--The co acid,” ispieces of zinc in lass or porcelain dish There will be bubbles and considerable heat evolved and zinc should be added until this action ceases and the zinc remains in the liquid, which is now chloride of zinc

This soldering acidwith a brush or swab For electrical work, this acid should be made neutral by the addition of one part ammonia and one part water to each three parts of the acid This neutralized flux will not corrode metal as will the ordinary acid

Powdered resin alvanized iron and aluminum Tallow, olive oil, beeswax and vaseline are also used for this purpose Muriatic acid alvanized iron without the addition of the zinc, as described inteaspoonfuls of sal ammoniac to each pint of the chloride of zinc is so Metal Parts_--All surfaces to be joined should be fitted to each other as accurately as possible and then thoroughly cleaned with a file, e in lye Workit into nitric acid which has been diluted with an equal volume of water The work should be heated as hot as possible without danger of , as this causes the solder to flow better and secure a ives better results than half and half, but is more difficult to work It is very i all work, otherwise the solder will only stick to the surfaces and will not join with the in which the surfaces of the work are first covered with a thin layer of solder by rubbing them with the hot iron after it has been dipped in or touched to the soldering stick These surfaces are then placed in contact and heated to a point at which the solderiswhere the form of the work permits it This is the onlyis to be placed over the end of a length of tube

_Soldering Holes_--Clean the surfaces for soht, and apply flux while holding the hot iron near the hole Touch the tip of the iron to some solder until the solder is picked up on the iron, and then place this solder, which was just picked up, around the edge of the hole It will leave the soldering iron and stick to thesolder in this way until the hole has been closed up by working fro toward the center After the hole is closed, apply more flux to the job and sh spots Should the solder refuse to flow s Seams_--Clean back from the seam or split for at least half an inch all around and then build up the solder in the sa, apply thwise to s Wires_--Clean all insulation froht Lay the ends parallel to each other and, starting at the middle of the cleaned portion, wrap the ends around each other, one being wrapped to the right, the other to the left Hold the hot iron under the twisted joint and apply flux to the wire Then dip the iron in the solder and apply to the twisted portion until the spaces between the wires are filled with solder Finish by s away all excess thwise The joint should now be covered with a layer of rubber tape and this covered with a layer of ordinary friction tape

_Steel and Iron_--Steel surfaces should be cleaned, then covered with clear muriatic acid While the acid is on the metal, rub with a stick of zinc and then tin the surfaces with the hot iron as directed Cast iron should be cleaned and dipped in strong lye to rerease Wash the lye aith clean water and cover with muriatic acid as with steel Then rub with a piece of zinc and tin the surfaces by using resin as a flux

It is very difficult to solder aluminum with ordinary solder A special aluminum solder should be secured, which is easily applied andjoint Zinc or phosphor tin may be used in place of ordinary solder to tin the surfaces or to fill shly heated before atte acid The aluhly cleaned with dilute nitric acid and kept hot while the solder is applied by forcible rubbing with the hot iron

BRAZING

This is a process for joining , except that brass is used to make the joint in place of the lead and zinc alloys which forpoint is less than that of sheet brass

Two pieces of brass to be brazed together are heated to a temperature at which the brass used in the process will a and perfect joint, which is far superior to any for where the work allows this process to be used, and infor the particular field in which it applies

_Brazing Heat and Tools_--Thewillthe parts to this te solid, liquid or gaseous fuels While brazing e, this method is seldo a sufficiently clean fire with s else is available Large jobs of brazing e, as this fuel produces a very satisfactory and clean fire The only objection is in the difficulty of confining the heat to the desired parts of the work

The as torch built for this work These torches are si the proper quantity of air with the gas to bring about a perfect coas torch, one line carrying the gas and the other air under a moderate pressure The air line is often dispensed with, allowing the gas to draw air into the burner on the injector principle, as burners for use with incandescent ulate the aas and air, and ordinarily the quality and intensity of the flaas is not available, recourseThis torch is built in the sa operations, with the exception that two regulating needle valves are incorporated in place of only one

The torches are carried on a fra handled Fuel is forced to the torch froasoline into which air pressure is puive the desired flame by means of the needle valves in much the sa liquid fuel