858 



THE FARMERS HANDBOOK. 



A 



The bar to be welded is upset somewhat, and a head formed 

 by driving it down into a bolster. The upset end of the bar 

 prevents it going right through, and a head is formed which 

 is given a conical shape with the hammer. Spikes and small 

 bolts can be made in the same way. 



To form the weld, the bar A is laid on the anvil and the 



scarfed end of B put into the cavity and struck a couple of 

 blows on the other end. The work is then turned to have 

 the bar A upwards, and B dropped into the bolster. The 

 head prevents it going right through and welding is done by 

 hammering down on A. 



These methods of scarfing and welding are given only as 

 Fig. 13. a guide and to illustrate the principles. Many other forms- 



Butt weld. are US ed, but the smith who grasps the idea of what is re- 

 ' quired can adapt himself readily to circumstances and devise 

 methods for himself. 



In welding, the length of the material decreases somewhat. A rough 

 rule followed by many practical smiths is to allow a length equal to the- 

 thickness of the bars for shrinkage. 



In the actual process of welding the scarfed points must be stuck together 

 as soon as possible, as these, being thin, cool out quickly. 



Drawing Down. 



This means the reduction of the size of a bar of iron by hammering whilst 

 it is at a high temperature. By proper direction of the blows the iron can be 

 drawn down into any shape without injuring the strength. This can only 

 be done at a high temperature and even then, the process is a slow one, 

 and only advisable when it means a saving of labour in other ways, or better 

 work being turned out. Where an article varies considerably in size at 

 different points, as, for instance, a pair of tongs, less labour will be involved 

 if a bar large enough to form the jaws is taken, and (after the jaws have 

 have been formed) is drawn down, than if a thinner bar is taken and 

 upset to give size for the thick section. In the case of tong-making, the 

 necessity of drawing down a thick bar sufficiently to form the handle i& 

 avoided by drawing down a little and welding on a sufficient length of a 

 thinner bar. 



A blacksmith at work may draw down, upset, or weld hi6 iron as it suits- 

 his purpose. As his whole object is to turn out work with the least amount 

 of labour, it is difficult to set definite limits to the place of each. 



The manner in which drawing down is done is determined by the kind of 

 work. If it is merely a matter of tapering off to form a point, as when 

 making a hook, the procedure is different from that followed when the size- 

 is suddenly reduced as in Fig. 14. 



