198 BLACKSMITHING 



increasingly soft, and, if another piece equally soft is touched 

 to the first, the two will stick; light tapping will complete the 

 weld. The greater the range of temperature thru which the 

 metal remains pasty, the more easily may it be welded. The 

 greatest trouble in welding is in heating the metal properly. 

 The fire must be clean and bright; otherwise, small pieces of 

 cinder, etc., will stick to the metal. The heating must be 

 slow enough to get the metal heated thru. Have all tools in 

 place before taking a piece of metal from the fire. Hold the 

 tongs on metal so that pieces can be easily placed in position 

 without difficulty. When "stuck," first tap the thin parts of 

 the pieces to be welded, as these cool first and most rapidly. 



Do not have an oxidizing fire in welding; that is, not too 

 much oxygen going thru fire. 



In the welding process, the oxide formed is really a flux. In 

 welding, steel will burn before the oxide becomes white hot; 

 hence, a flux is used made of sand and borax ; this is put in at 

 yellow heat and protects the surfaces to be welded, preventing 

 the forming of oxide. The oxide melts at a much lower heat 

 when combined with the flux. This is the principal object of 

 using a flux. Sal ammoniac seems to clean the surface, so a 

 flux is sometimes made of one part sal ammoniac and four 

 parts borax. 



The following typical welds should be familiar: 

 a) Fagot or pile. f) Chain-making. 



6) Scarfed. g) Butt. 



c) Lap (flat). h) Jump. 



d) Lap (round). i) Split. 



e) Ring (round stock). j) Angle. 



k) "T" (round stock). 



