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for quickly removing the dies for cleaning as it was expected that 

 soaking them in acetone would be necessary at frequent intervals. 



The density and viscosity of the cellulose acetate solution have an 

 important bearing on the process. It was desirable to use as little 

 acetone as possible as this would hasten the drying operation and with 

 less acetone in the process, less acetone would be lost. 



To obtain the maximum effect from the film of cellulose acetate, it 

 was desirable that the coating be as free from extending fibers and as 

 smooth as possible. Passing the coated wire while still plastic over 

 pulleys so arranged that the entire circumference of the wire would 

 come in contact with the pulleys, was found to produce a polishing 

 effect. 



Fig. 5 — -An installation of machines for treating textile insulated wire with cellulose 



acetate. 



Commercial Installation 

 With the essentials of the cellulose acetate coating process deter- 

 mined, the design of a commercial machine was undertaken. Figs. 5 

 and 6 show a number of these machines which, it will be seen, are in 

 many ways similar to the experimental machine previously illustrated. 

 Each head is separately driven by a two-speed electric motor and there 



