220 METHODS OF COMMUNICATION FOR FOREST PROTECTION 



Copper rapidly oxidizes when heated in contact with the air, and solder will not 

 adhere to oxidized copper. The purpose of the flux, therefore, is to cover the surface 

 to be soldered while the temperature is still low, and prevent oxidation. Continue 

 the application of the hot iron until the joint has become hot enough to melt the solder 

 which will then flow readily. Do not try to apply resin-core solder with a hot iron 

 and its own flux to a cold surface nor to an oxidized joint. 



45-55 Solder. This solder is to be used for joining split sleeves in cable work, 

 and for large surfaces of metal which are to be soldered. It is also to be used in making 

 joints in old galvanized-iron wire, and similar work. In joining old galvanized wire, 

 clean the ends which are to be soldered with emery cloth and make a Western Union 

 joint; then solder by means of a ladle, using as a flux one of the approved stick forms. 

 Do not use more than is necessary to cause the solder to flow, and apply by rubbing 

 before the first pouring of the solder over the joint. If necessary, apply again after the 

 joint has been heated. A large well-tinned soldering iron may be used, if preferred, 

 instead of pouring the solder over the joint. In such a case the iron must be pressed 

 against the joint so as to warm it just enough to melt the flux when it is held against 

 it. After a coating of this has adhered, apply the hot soldering-iron again and, at the 

 same time, apply the 45-55 wire solder to the joint (do not put the solder on the 

 soldering iron). Wheii the solder melts, having derived its heat from the joint and 

 not from the iron, it will flow readily. A slight tap on the wire will help it to run 

 into the joint well. This solder is furnished in the form of i-in. wire in 10-pound 

 coils, or in bars of 1 pounds weight, and orders must state in which form it is 

 required. 



Resin Flux Wire Smolder. Resin flux wire solder is to be used in solderiiig all wire 

 connections other than galvanized-iron wire, but it may also be used for this purpose 

 in new work, when it is done with a soldering-iroTi. It is also to be used for all work 

 where copper and brass are to be soldered. To use this solder for small work, such 

 as wire joints and terminals, apply to the joint a well-tinned soldering-iron, of suffi- 

 cient size for the work. In soldering terminals, first clean off all old solder and bits 

 of wire by meaiis of a hot iron and then give only one turn of the wire which 

 is to be soldered around the terminals. In larger work, use any convenient means to 

 heat the joint, remembering to get a coat of resin on before enough heat has been 

 applied to the metal to oxidize it, and that the metal to be soldered must be hot enough 

 to melt the solder and burn off the superfluous resin. This solder is furnished i-n 

 5- and 10-pound coils, and orders must state which size is required. 



To Solder to Black Iron 

 (1) First thoroughly clean a strip on the pipe about |-in. wide and 2^-in long; 

 ('2 1 ) Heat the cleaned place, either with the flame of a gasolene torch or a heated 

 iron, until it is hot enough to melt the soldering-stick; 



(3) Distribute a coat of flux over this point by rubbing it with a soldering-stick; 



(4) With a well heated soldering-iron distribute 45-55 solid-wire solder over the 

 cleaned space; 



(5) Tightly wrap the wire, well cleaned, around the pipe, leaving at least f in. 

 between each turn; 



(6) Fasten the end of the wire at the end of the coil by twisting it around the 

 wire leading from the pipe; 



(7) Apply an additional coat of flux; 



(8) Apply the 45-55 solid-wire solder in the regular manner. 



Tinning Soldering-iron. File the iron to the required shape and brightness, and 

 heat until it is only just hot enough to melt the resin of resin-cored solder but not 

 hot enough to change the colour of the bright copper by oxidatioii. When in this 

 condition, coat the part to be tinned with resin and apply heat until the solder melts 

 readily, when it will be found to flow freely on the iron. Do not let the flame come in 

 contact with the tinned part of the iron. 



