RUBBER MANUFACTURE. 



Ill 



parts of water. Three drams of this mixture will be used per 

 gallon of latex. During the first two or three minutes of 

 working, the machine should be driven at a speed of about 180 

 revolutions per minute (30 revolutions of driving handles). At 

 the end of this time the sound from the cylinder will have become 

 deadened and the latex in the centre will have taken a creamy 

 appearance. The speed should then be reduced to about 120 

 revolutions (20 revolutions of handles), and a little later to 100 

 (16 or 17 revolutions of handles). The coagulated rubber should 



begin to form into a spongy 

 mass between the blades and 

 in the centre of the pan in four 

 minutes from the time the 

 machine starts working, and 

 in five minutes the process 

 should be complete. To prove 

 that separation of rubber is 

 complete, put a stick down 

 behind one of the blades and 



FlG. 19. Sectional Diagram of the " Michie-Golledge" Rubber Coagulating 

 Machine. 



run the water adhering to it on to some convenient spot on the 

 top of the machine, when it will be seen that the water is quite 

 clear and free of rubber globules. 



"In case separation is not perfect it will probably be found 

 that in the finishing off, the machine has been run too fast. A 

 minute or two longer at slower speed will put this right. The 

 mass of coagulated rubber should be at once removed and rolled 

 out into sheets before it hardens. 



"Rolling. If a ' Dolly' mangle is used, lumps pulled off the 



