B60 THE farmers' handbook. 



The cooling of the bar prevents it being drawn down very much after each 

 heating. The thickness of the bar, the quality of the metal, and the skill of 

 the smith determine the amount. As a rule, with ordinary sized work, about 

 1 \ to 2 inches are all that can be drawn down at each heating with safety. 



When the size has been reduced sufficiently in square form, finishing off is 

 commenced. The corners of each side are hammered flat, forming an eight- 

 sided section. The corners are again flattened, until finally the round form 

 is obtained. This procedure must be carefully followed, otherwise the iron 

 will split. 



When a bar is to be merely drawn down to a point, fullering is not done, 

 but the procedure is otherwise the same. 



Upsetting, or Jumping Up. 



This is a process followed by smiths to increase the bulk of metal at a certain 

 point, and is the reverse of drawing down. It takes more time and care 

 than the latter. A high temperature is required, and the heat must be 

 localised — that is, confined to the spot where the upsetting is to be done. It 

 follows therefore that a bar can be upset either at the ends or at any point 

 along its length. 



Different methods' are followed. The bar may be taken in the hands and 

 jumped down vertically on the anvil ; it may be laid on the anvil and upset 

 with the sledge ; it may be held in the vice and upset with the hammer ; or 

 it may be held vertically on the anvil and upset in the same way. 



When upsetting, it is necessary to see that the spread of the metal is in the 

 right direction. If the blows are not carefully delivered, and the work 

 straightened as required, the thickening may be in the wrong direction. 

 During upsetting the fibres in the iron are forced apart, and hammering must 

 be done after upsetting to restore the close texture. 



Punching. 



Different methods of punching are followed. Where it is not desired to 

 expand the size of the section, a punch only a little smaller than the hole 

 required is used. The metal is held over a bolster, or the hole in the anvil, 

 and punched half-way through, then turned over and punched from the 

 opposite side. A piece of the iron is punched out, leaving a hole nearly the 

 right size. It is finished up to the correct dimensions by tapping in a 

 mandrel and working on this. By this method a good deal of the metal is 

 taken out, but the size of the section is not increased. 



Another method is to punch out a small hole and gradually expand thifr 

 hole with tapered tools until it is sufficiently large. When the holes are thus 

 punched, very little metal is cut out, but the iron is swelled outwards a good 

 deal. The eyes in hooks are often made in this way. 



Tempering. 



The temper of steel means the degree of hardness and the condition of the 

 grain. Temper in rough tools is generally obtained by heating the steel and 

 then cooling in cold water. If the temperature is too low the steel will be 

 left soft, with a coarse grain, while if it is heated too much the steel will be 

 brittle, and will probably have a coarse grain. The cooling also plays an 

 important part. If it is too rapid the steel will be very hard, while if '+• is too- 



