THE PULLEYS AND BELTING OF A SEPARATOR 213 



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 have good pulling 

 power. They 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 with a coat of 

 "Case" dressing once in about thirty days. It keeps the 

 belt waterproof and pliable and greatly increases its power 

 transmitting qualities. Linseed oil paint is sometimes 

 used, but it is objectionable because it will dry and render 

 the belt so stiff that it is liable to crack. Therefore, it 

 should not be used, except, possibly, on a belt that is nearly 

 worn out and is soon to be discarded. If impossible to 

 get dressing, use castor oil the crude if obtainable. In 

 an emergency, cheap laundry soap, containing rosin, will 

 help out. 



Lacing a Belt. Many make a mistake in thinking that 

 the heavier a lacing is made, the more durable it will be. 

 This leads them to make the lacing so thick and clumsy 

 that the belt is strained in going around the pulleys, caus- 

 ing the lace to wear out in a short time and probably the 

 belt to be torn between the holes. A good lacing is as sim- 

 ilar as possible to the rest of the belt, so that it passes over 

 the pulleys without shock or jar. To lace a belt begin by 

 cutting off the ends of the belt square, using a try-square 

 for this purpose, especially on the wider belts. Use a 

 punch small enough so that the lacing will fill the holes, 



