October 1, 1919.] 



THE INDIA RUBBER WORLD 



shown on page 288 of "RuljbiT Machinery" l)y Henry C. Pear- 

 son. .-MI linings and nets, friction stocks and cloth coated on 

 both sides were ground up and used in a fibrous compound as a 

 covering for inside work known as "rag." Screens of various 

 mesh were used from Yz to 3/16-inch. It was found to produce 

 a much more uniform "rag" than the old method of running the 

 scrap over the cracker directly, and made it possible to use up 

 many more kinds of scrap. 



Cloth used for tennis tops, whicli formerly had a poor sale 

 baled up as scrap, especially the doubled or "stuck upper" which 

 could not be sold at all, was all ground up to make fiber for 

 fiber soles and heels. Bad heels were pulverized to be used over 

 again in the cheaper grades. In fact, the only scrap to be 

 sold under the new arrangement is cut shoes, tires, cured trim- 

 mings, and tube wrappings. Constant touch is maintained with 

 the chemical laboratory which has been of valuable assistance 

 in working out compounds to make use of scrap. 



In brief, this is the system devised for handling the scrap 

 problem in one rubber factory. That it has been successful is 

 shown by a 2 per cent decrease in scrap which has been main- 

 tained for several months, and further reductions are looked 

 upon not as a possibility but as a certainty. 



GOVERNMENT SPECIFICATIONS FOR BALLOON 

 FABRIC. 



AS the following specifications are subject to revision, man- 

 ufacturers are advised to apply to the War Department. 

 Air Service Engineering Division, Dayton, Ohio, for the latest 

 rulings. 



SPECIFICATION NO. 18,013-A, MARCH 25, 1919, 



No. 16,01 J 



1. This specification covers 

 Production for balloon fabric 



2. Balloon fabric is rubberi 



GENERAL, 

 the requirerr 



Type, 

 balloon 



and should accompan 

 fabric. 



USE. 

 the various grades 



' Envelope 

 Ballonet , 



[ Tape .'.'.'. 

 Envelope 

 Ballonet , 



[Tape .... 





Fabric Number 



by addii 



MATERIAL, 



6. Balloon fabric shall be manufactured from finished balloon cloth 

 conforming in every respect to Specification No. 16,023-B. 



7. The rubber coating used in balloon fabric construction shall contain 

 the best quality rubber and the highest grade ingredients designed to give 

 iniuinium pci aieability and the best weather-resisting qualities. 



Workmanship shall be 

 Balloon fabric must i 

 re water-marks. The 



SIAJfUFACTURE. 

 :onsi5tent with the best manufacturing i 

 ot be overcured or undercurcd nor si 

 any of these conditions 



be determined by the Chief of Balloon In 



an angle of approximately 45 degrees to the straight ply. 

 SELECTION OF TEST SPECIMENS. 

 11. Samples. A sample for tests shall be taken from 



13. Each sample taken from the roll shall be one-half (J^) yard long 

 and the full width of the roll. 



14. Specimens. Tensile ti 

 two (2) inches wide, lihall be 

 of threads to be tested. 



Met I 



15. Three specin 

 be cut parallel to 

 the filling, as showi 



16. Three specin 



of 



e-ply fabric ( 

 warp, and three spec: 

 n Figure 1. 



s of two-ply bias fabric shall be cut parallel to each 



der test as indicated by the arrows in Figure Z-; 



three specimens being cut parallel to the warp of the straight ply, three 



parallel to the filling of the straight ply, three parallel to the warp of the 



bias ply, and three parallel to the filling of the bias ply. 



TESTS. 



17. Tensile Strength Test. The tensile test specimens, prepared in 



accordance with the foregoing instructions, shall be tested under existing 



humidity conditions. 



The 



spec 



19. The jaws of the t.sii " 

 shall be three inches apart r 



separate a't the rate of appr. ; 



20. The avteiage breaking I I ; i 



tion shall be taken as the tensile stn-nuih uf tl 

 sent. The tensile strength ot the balloon fat 

 that shown in Table 2 



21. Permeability. The permeability of th 

 be determined, under the following conditions, 

 approved by the Inspection Department of th( 



icn in a machine of the 

 ty of 400 pounds. 



21/16 inches wide and 

 the test. The jaws shall 



:ciniens cut in each direc- 

 sample which they repre- 

 : must be not less than 



The fabric 



hall 



: fabric to hydrogen shall 



by a method and apparatus 



Bureau of Aircraft Produc- 



with an atmosphere of pure 



Tensile 

 Strength 

 (Minimum 

 per Inch 

 Width). Warp 

 and Filling, 

 Pounds, 



