22O SCIENCE OF SUCCESSFUL THRESHING. 



However, it is true that any separator will waste con- 

 siderable grain if improperly operated. When there is reason 

 to believe that a machine is wasting more than it should, 

 first determine whether the grain is being carried over in the 

 chaff or in the straw. 



If the Waste be at the Shoe, catch some of the chaff from 

 the conveyor sieve and if grain be found, see that the sieve 

 is properly adjusted for the kind of grain being threshed. 

 If a common sieve be used, it should be coarse enough for 

 the grain and its lips should be sufficiently bent open. Too 

 high a speed will cause grain to be carried over the conveyor 

 sieve. Do not use any more concave teeth than are neces- 

 sary as the extra amount of chaff makes difficult work for 

 the sieves. See that the blinds are adjusted so that the blast 

 is no stronger than is necessary to clean the grain and keep 

 the sieves working freely. If grain be still detected, open the 

 adjustable conveyor sieve a little more. It should not be 

 opened so much, however, as to overload the shoe sieve. The 

 wind-board should throw the strongest blast about half way 

 back on the conveyor sieve. Carrying "traps" in the fan 

 drum is liable to bend down this board which in some cases 

 becomes so sagged that some kernels slide over it into the fan, 

 are struck by the fan wings and thrown entirely out of the 

 machine. 



// waste be caused by failure to separate the grain from 

 the straw, first see that the speed of the crank is 230. The 

 cause may be poor feeding which produces "slugging" of the 



