164 



THE INDIA RUBBER WORLD 



the calender the crimp of both the warp and the tiller is alike. cross above and below tlic large warp 



to lock or 



It should be noted just here that the carcass is built, not of steady it 



one type of fabric, but of several. These are the bu 

 the breaker strip fabric, the challng strip fabric a 

 fabric. 



The standard carcass fabric which has been undc 

 tion is 17; 4 ounces in weight per square yard, an< 



ilding fabric. The "chaling strip" is a fabric used to cover the beads and 



111 tlie bead ibe lower part of the casing. The name is self-explanatory. The 



weave is square, the weight varying according to the size of 



r ciinsidcra- lire, and the threads are crimped. In some it is an S'^^.-ounce 



is made uf fabric, in others 9,'s ounces, etc. 



«-*■ «-»^l| r^ t^ rt 





i%» VJ 



.*■■>•****•«' ;<i 



St.\.\D.\RD BviLDlNC F.VBRIC, 



17'-.' Ou^•CEs. 



Breaker Strip hABRic, 

 Squ.\re We.^ve. 



Bre.\ker Strip F.\bric. 

 Lend We.we. 



and 



Sea Island cotton, from combed and carded Egyptian 

 sometimes from carded Peeler yarns. 



Upon the outside of the carcass is a wall of rubber, and upon 

 this is laid what is known as tlu "breaker strip." The purpose 

 of this strip is to bind the carcass and the tread intimately to- 

 gether; or, to put it popularly, to ri\et them. The breaker strip 

 fabric is of square weave and an open mesh composed of heavy 

 yarn or cords, and weighing anywhere from 11 to 13 ounces per 

 square yard. The breaker strip is a single layer, and in the 

 best tires is made of Sea Island cotton and heavily coated with 

 high-grade rubber. The fabric has to be strong and capable of 

 standing up under the sidewise and the lengthwise stresses, and 

 must support the tread of the tire effectually. 



Ill the older style of breaker strip material, the square weave, 

 with the open mesh, did not give the fabric stability or stiffness. 

 It was so yielding that it could not be run evenly through the 

 calender, and it was hard to apply the rubber coating uniformly 



Tire beads are built up on a rubber core; or, in the case of 

 a clincher tire, on a wire core, and covered with fabric. The 

 bead is then given its proper shape by molding. The fabrics 

 used in the beads are not standardized. However, 8 to 14- 

 ounce fabric is recommended by many builders of reliable tires. 



in addition to the regular bead fabric, what is known as 

 thread fabric is used for tire beads. The base of this 

 fabric is a singie yarn that is twisted two-ply and reversed, and 

 then twisted three-ply. Such fabrics used are loosely woven 

 materials consisting primarily of singie heavy warp cords held iti 

 place by widely spaced thin threads, the sole duty of which is to 

 hold the warp in place. This fabric is calendered without regard 

 to the fact that the threads may ride one another. The elasticity 

 of thread fabric is increased by cabling, which means twistin.ij 

 with other threads, and crimping. 



When thread fabrics are used for building up the carcass, 

 which is rarely, they are proofed on a spreading machine and 



D Thre.40 F.> 

 8 Ounce. 



and satisfactorily. Because of this a moditication was necessary, 

 and the present improvement, called the "Leno" weave, is now 

 e.xtensively employed. In this fabric the warp and the filler yarns 

 are locked so that the material resists the spreading effect of 

 the calender rolls without distortion. There is a single heavy 

 warp yarn running in one direction with two smaller fillers that 



then cut on the bias and rolled up with liners ready for the 

 building macliine. 



Thus it is seen that the fabric or fabrics of which a motor 

 tire is formed are fully as important as the rubber, .\s the 

 United States is today by far the greatest tire making country 

 in tile world, and as the promise for the New Year is for even 



