FARM MACHINERY 



285 



these is the older type. It has a rather large capacity for 

 the amount of sieve surface provided, and when properly 

 handled will do good work. The latter type, however, has 

 the greater refinement and is capable of more careful selec- 

 tions. 



The Selection of the Fanning Mill. There is a tendency 

 among certain manufacturers to build a fanning mill of such 

 light construction as to be neither durable nor able to with- 

 stand hard service. These mills soon become rickety and loose 

 in all of the joints. Therefore, in making a selection of. a fan- 

 ning mill, after deter- 

 mining definitely that it 

 will do the desired work, 

 it should be carefully 

 examined to see whether 

 or not the frame and 

 the body of the machine 

 are made of good mate- 

 rial and well put to- 

 gether. Wooden keys 

 and nails as means of 

 fastening the joints 



should be guarded against. The shoe which carries the sieves 

 should be well made to withstand the constant vibra- 

 tion to which it is subjected, and conveniently arranged 

 for the adjustment of the sieves. It is best that the length 

 of the shaking stroke be subject to adjustment, as small 

 seeds require a shorter stroke than large ones. 



Operation and Care. The air blast should be subject to 

 regulation, either by changing the speed of the fan or by 

 varying the volume of air supplied, which will permit it to 

 be adapted to all conditions. Too little attention is often 

 given to the construction of the sieves. The frames should 



Fig. 180. 

 which the blast is 

 through the sieves. 



A section of a fanning mill 



directed below an-i 



