558 



THE INDIA RUBBER WORLD 



[July 1, 1919. 



BUILDING BIAS BINDING. 



IN THE MANUFACTURE of tcnnis shocs, as well as other shoes 

 having uppers of duck, canvas or other fabrics, a very con- 

 siderable amount of binding is used to cover the raw edges to 

 prevent unraveling and to give finish to the goods. 



Some of these bindings are cut the straight way of the cloth, 

 others are cut on the bias, that is, at an angle of 45 degrees to 

 the weft and warp threads of the fabric. The advantage of 

 these bias bindings is that they lie flat when bound around 

 curved edges or when turned around comers, as is necessary 

 when binding the top of a shoe and continuing down the sides 

 of the lacing opening. 



Simple as this product seems, there are details in its manufac- 

 ture which producers guard closely, and decline to divulge, for 

 there are manufacturers whose sole business is to make these 

 bindings of various materials, and of colors to match the textiles 

 with which they are used. 



THE METHOD OF MANUFACTURE. 



The illustrations show the manner in which such bindings are 

 made in a leading tennis-shoe factory. The method used is 

 somewhat similar to the production of frictioned duck for the 

 manufacture of tire casings, though of course this cloth is not 

 frictioned but is used just as it comes from the mill, or is stif- 

 fened by a proper sizing. 



The cloth is run, a number of thicknesses at a time, under a 

 descending knife set to cut at an angle of 45 degrees, in other 

 words, through a bias cutting machine. The diamond-shaped 

 pieces are joined at their selvages, either by sewing or cementing, 

 thus forming a continuous web which is wound tightly on a metal 

 mandrel. This roll is then placed in a machine like that shown 

 in the illustration, and from this wide roll, narrow ones are cut 

 by a rapidly revolving circular knife which is adjustable to cut 

 rolls of any desired width. 



THE USES OF BIAS BINDING. 



Such bindings, sometimes plain, or stiffened with starch or 

 glue, are used for seam stays in variou.<; manufactures, and as 



Folding Bias Binding. 



back stays in shoe manufacture. By far the larger use is for 

 binding the edges of cloth which would otherwise ravel out. It 

 is used around the tongues of oxfords and boots, and also along 

 the lace stays and around the tops of canvas footwear, unless 

 the material itself is folded in and stitched to form a finish. 



FOLDING. SEWING AND MEASURING. 



For this purpose the binding must itself be folded that its own 

 raw edges be concealed and protected. Various devices are used 



for such folding, some of which do the work and rewind into 

 compact rolls, while others are attachments to the sewing ma- 

 chines, which take in ihe flat binding, fold in each edge, and 

 feed it to lap over the material to be bound, so that ont i.tiich- 

 ing passes through both edges of the binding and the material 

 between. During this operation the binding is also measured 

 oflF into exact lengths to fit the part to be bound. 



BIAS BINDING MATERIALS. 



These bindings are made mostly of cotton cloth, usually white, 

 brown or black for tennis shoes, though poplin and even satin 



Cutting Bias Binding. 



re used by slipper manufacturers. Such bindings are also used 

 1 finishing many other different articles, such for instance as 

 less shields, in which case they are made from material the 

 ime color as the articles to be bound. Some bindings are cut 

 mm fabrics imitating leather, for use by the manufacturers of 

 ncket-books. In fact, the uses for this seemingly unimportant 

 lie of goods are so many and varied that large factories are 

 evoted exclusively to the production of the many varieties. 



GOVERNMENT SPECIFICATIONS FOR RUBBER SHEETING. 



M. H. Specifications. 

 Material. Shall be a cotton fabric, thoroughly coated with a white 



Limpound, single coated, 

 4uare yard. The rubber 

 pou the sheeting. The rubber .sheeting sha 

 Finish. The rubber sheeting shall have 



not less than 13 ounces per 



ndered and : 

 be vulcanized by open steam. 

 1 smooth, uniform soft finish. 



sheeting shall be not less than fifty-three (53) 



Till 



and sha 



)er sheeting shall show on analysis not less 



compound. The rubber compound shall consist 



than 30 per cent by weight of new and unrecovered rubber 



how on analysis not over 4 per cent of its weight of organic 



accione extract, nor over 2 per cent of its weight of free sulphur. 



Tensile Strength. The rubber sheeting shall have a minimum tensile 

 strength in the warp of forty (40) pounds, and in the filling of thirty-five 

 (35) pounds. Tlie tensile strength shall be determined by using the strip 

 method (.n strips 9 inches long by 1 !4 inches wide from both the warp 

 and filling diiections of the fabric. The strips to be "' " 



cth. 



xactly 

 changed when 



Tests. The condition of rubber sheeting shall t( 

 ubmitted to the following tests: 



(1) Subjected to urine for 18 hours. 



(2) Suljjected to 5 per cent phenol solution for 18 hours, 



(3) Subjected to steam at 240 degrees F. for two periods of twenty 



minutes each. 

 The tests and analyses to be conducted in accordance with the pro- 

 if Standards. 



edure followed at the 





Packing. The 

 50-yjrd lengths, and net more 

 at least J4-inch (finished size) 

 01 spruce prefeired. and must 

 Ends to be reinforced by two 



1 in rolls of approximately 

 the box. Boxes to be of 

 her, tong'ied and grooved, white pine 

 ew and of appropriate make and size. 

 g perpendicular to grain erf 



Div 



Washington, 



