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THE INDIA RUBBER WORLD 



[September 1, 1920. 



ARTISTIC MOLD WORK. 



By Arthur C. Siliiircs. 



THERE ARE almost as many grades of mold work as there are 

 states in the Union. Some work is coarse and without finish. 

 Other is in color, texture, and finish, a product of great perfec- 

 tion. To this last-named class belongs the molded rubber grip 

 used on hose supporters. Goods of this sort come under the gen- 



Garter Button Mold. 

 eral trade term "notions." As they are sold by the dry goods 

 trade they must, of necessity, look at least as well as the dainty 

 fabrics that are their counter mates. Of these goods some are 

 wholly of rubber and some of both rubber and fabric. Where 

 the goods are to present a fine appearance, and one side shows 

 fabric, the molding involves considerable skill and processes not 

 usually followed. The soft rubber garter grip is of this sort and 

 merits especial description. 



Beginning with the compound: this is of an extra whitness 

 secured by a formula of w^hich lithopone is the base, a little ultra- 

 marine blue being added to get a blue-while. The compound 

 is very rich, that the soft effect of pure rubber may be attained. 



From the warming mills the snow-white compound goes to a 

 three-roll calender which applies in two operations a continuous, 

 thin coating of the stock to both sides of a web of unbleached 

 sheeting. As the rubberized fabric finally leaves the calender it is 

 wound up on a stock shell with a cotton liner between the 

 gummed surfaces to prevent their sticking together. 



The calendered stock is then cut into pieces conforming in 

 width and length to the button mold, and placed in "books" for 

 convenient handling. 



The rubber button stock is of the same snow-white compound 

 as that used for coating and sheeting, and is run through a tubing 



each cavitj-, and a full-sized sheet of the calendered sheeting stock 

 is laid over the buttons to which it adheres. The top plate is then 

 placed over the sheeting and the mold and its contents are ready 

 for the cure that is effected in a vulcanizing press. After vul- 

 canizing, the .sheets containing the buttons are removed, the mold 

 refilled, vulcanized and so on. 



The next step is bleaching — that is accomplished in a wood 

 lank containing water and chloride of lime, into which a live- 

 steam pipe opens. The button sheets are placed in the tank and 

 bleached by the boiling solution. After being dried by tumbling 

 the sheets are ready for the stockinette that is to be applied to 

 the back of the tab. 



The snow-white stockinette is passed through the 3-roll calen- 

 der, where it is coated on the unfinished side with a special white 

 compound and wound up on a stock shell, no liner being required. 

 The roll of stockinette is then placed in a slitting and rewinding 

 machine that cuts the roll into strips, equal to the width of the 

 button mold, and rewinds the strips on reels. 



After the vulcanized button sheets have been coated on the 

 back with a special cement they are ready to be "backed" with 

 stockinette. This is done on a two-roll doubling machine that 

 applies the stockinette to the backs of the button sheets, and cold 

 cures at the same time. K wood or metal template is employed 

 for holding the button sheet in place during this operation. A 

 number of doubling templates can be used to good advantage. 



The button sheet is now placed in the template with the buttons 

 down, and a cold-curing solution brushed over the cemented sur- 



Bleaching Tank. 

 machine provided with a die conforming to the size of the button 

 cavities in the mold. As this continuous cord is extruded from 

 the tubing machine it is cut into small pieces of the proper size 

 to fill exactly each mold cavity. 



The 144-cavity steel button mold is ori^nally made in three 

 parts for convenience in die sinking, the two sections which form 

 the rubber tab being riveted together while the third section or top 

 plate is loose. After warming the mold slightly and dusting it 

 with soapstone, pieces of the white button stock are inserted in 



Stockinette-Applying Machine. 



face of the sheet, after which the template is placed on the platen 

 of the machine. The end of the coated stockinette strip being 

 drawn down from the reel is passed around the pressure roller 

 and alined with the end of the template to which it adheres. 



When the machine is operated by turning the hand wheel the 

 template passes under the pressure roller that doubles and applies 

 a sheet of stockinette to the button sheet. The web is severed and 

 another template placed in the machine, and the operation re- 

 peated. 



The button sheets backed with stockinette are fully cured in 

 about 30 minutes, after which the button tabs are died out with 

 special cutting dies and sent to the finishing department, where 

 they are assembled. 



Ames Holden McCready, Limited, Montreal, Quebec, has 

 promoted N. M. Lynn, formerly manager of its Edmonton branch, 

 to middle western sales manager, with headquarters at its Win- 

 nipeg, Manitoba, office. He will have charge of sales in the pro- 

 vinces of Manitoba, Saskatchewan, and Alberta, with division of- 

 fices and warehouses at Winnipeg, Regina, and Edmonton, and 

 branch offices and warehouses at Saskatoon and Calgary. In 

 addition to the lines of shoes, canvas, felt and rubber footwear 

 already carried, all of these warehouses will be stock and dis- 

 tributing points for Ames Holden tires as soon as these are on 

 the market in suflScient quantity. 



