PART IV 



SHEET- METALWORK 



CHAPTER XXII 



TOOLS AND SUPPLIES; FUNDAMENTAL PROCESSES 



204. Need for Sheet-Metal work on the Farm. There 

 are many opportunities about the farm for sheet-metal re- 

 pairs and construction, especially in tin work. Kitchen uten- 

 sils, the equipment of the dairy and creamery, farm machines, 

 water and sanitary systems, and roofs and gutters on build- 

 ings, all furnish problems in sheet-metalwork. 



The chief operation in sheet-metalwork, aside from calcu- 

 lating sizes and cutting the metal, is that of fastening, which 

 maybe divided into three classes, viz., soldering, brazing and 

 riveting. Welding is not included, as it seldom is used in 

 working sheet metal, and, besides, it is considered under the 

 heading of Forge Work. 



205. The Process of Soldering. Soldering is the process 

 of joining two pieces of metal by means of a more fusible 

 metal or metallic alloy. The metal, or alloy, called solder, 

 should be selected with the following considerations in mind : 

 (1) Its strength should be as great, or greater, than that of 

 either of the pieces of metal it joins; (2) its color should be as 

 nearly as possible that of the joined metals, and (3) its fusing 

 point should be considerably lower than that of either of 

 them. 



206. Classes .of Solder. Solder is classed as soft or 

 hard, depending upon the degree of fusibility, and, to some 



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