THE BELTING OF A SEPARATOR. 2O % 3 



while light, especially direct sunlight, and extreme dryness 

 tend to rot the rubber. 



The Main Belt is usually of rubber or stitched canvas in 

 widths of six, seven or eight inches, and made endless in 

 lengths of 120, 150 or 160 feet. The object in having it so 

 long is to place the engine far enough from the grain to be 

 safe from fire. Accordingly, the 120 foot length may be used 

 when the fuel is coal, but when burning wood or straw, the 

 longer lengths should be used. The usual arrangement of 

 the stacks in the locality the rig is to operate in, must also 

 be taken into consideration in choosing the length of belt. 

 With the engine having a forty inch fly-wheel and running 

 at 250 revolutions per minute, the main belt will travel 2625 

 feet, or almost exactly one-half mile in a minute. A belt 

 has a greater tendency to slip on the smaller of the two pul- 

 leys over which it runs and for this reason, the cylinder pul- 

 ley is covered with leather or similar material. When the 

 cover is worn out, a new one should be put on as no main 

 belt will pull well on a bare cylinder pulley. Rubber belts 

 pull well at all times, and do not require dressing, in fact, 

 any dressing is injurious, because it has a tendency to pull 

 off the outer coating of rubber. To obtain the best results, 

 stitched canvas belts, however, should be treated to a coat 

 of dressing once in about thirty days. Linseed oil paint is 

 often used, and it is better than no dressing at all, but the 

 regular dressing sold for this purpose is preferable, as it 

 keeps the belt waterproof and pliable and greatly increases 

 its power transmitting qualities. 



