cont'd from part 1
Fig 2 shows one of the larger presses which has a table 8 feet wide and is designed for the largest belts used in textile mills or in dynamo driving To insure a neat joint and a straight belt great care is taken to bring the sides of the strips of belt to be glued in a straight line and when this is done and the scarfs are bought to the correct position a steel straightedge is placed on top of the lower belt and Fig 4 The Finishing Machine against the end of the upper belt which latter is then removed and the scarfed end of the lower belt is scraped off slightly up to the line of the straightedge thus making an accurately formed seat for the bevel of the upper belt This results in a joint with no ragged or projecting edges In cementing a stiff brush is used to rub the cement into the pores of the belt only a small quantity of the adhesive being applied and then the joint is placed under the press for several minutes while hydraulic pressure is applied and the cement allowed to set When a belt 50 or more inches wide Is required parallel strips of leather must be joined together and this is done by butting the pieces longitudinally and allowing the two thicknesses of leather or three thicknesses according to whether it is a double or triple belt to overlap and break joints as in Fig 3 After the required length of belt has been glued up It passes to the finishing machine The belt is here drawn between stationary knives which are set the required distance apart to trim the edges of the belt rounding them slightly and making the belt of a uniform width In its passage coiled is driven by a train of gearing and by this means the belt is drawn through the machine under tension Various kinds of belting are made to suit the requirements of customers A belt with cemented lap joints is considered to be as strong at the joints as at any other point but some customers prefer to have the joints riveted also Certain brands of the highest grade double and triple belts are stitched lengthwise with heavy thread to render them doubly secure against pulling apart The same object is also attained by screw fasteners The screws are originally in the form of a threaded wire wound on a reel mounted on top of the hollow spindle of the machine that inserts the fasteners The wire passes down through the center of the spindle and is gripped by a chuck at the lower end As the spindle rotates the wire screws itself into the belt a predetermined distance at which point it is cut off just beneath the surface of the belt by cutters or Fig 5 Diagram showing Mechanism of Finishing Machine through this machine the belt is stretched and it also travels under a large wheel in the rim of which is a numbering die the circumference of the wheel is 10 feet so that at each revolution a number is stamped on the belt indicating its length in feet The belt is finally coiled or wound on an arbor In Figs 4 and 5 are views of the finishing machine which are self explanatory The arbor on which the belt is Fig 6 General View of Finishing Room nippers controlled by the machine Belts which run in damp or otherwise unfavorable locations must be made water and oil proof Especially is this desirable in the case of belts for dynamos or other rapid running machinery where oil is likely to be thrown off the pulleys onto the belts Link belts are manufactured here round belts braided rope belts and other products of a like character The leather used by Charles A Schieren & Co comes from their own tannery at Bristol Tenn This is in the heart of the oak country since oak tanned leather should be exclusively used for a high grade product like belting The bark is stripped from the trees in the spring when the sap begins to flow up Into the trunk and limbs of the tree and is stored in sheds where it seasons for future use The hides which come from the slaughter houses of the West are washed in water to remove the dirt then placed in vats of weak lime water for several days until the hair has been loosened sufficiently to allow it to be scraped off with a blunt knife The hides are then saturated by a neutralizing solution called bate which removes the lime and then they are ready for tanning The bark is crushed and delivered to leach tubs where moisture is applied by means of rotary brass sprinklers The water filters through this mass carrying down the tannic acid which is collected and used in the tanning vats The process of tanning requires in all a period of 120 days after which the hides are oiled on the grain side then hung up in a darkened loft where they are kept at an even temperature and gain a clear russet color which characterizes leather prepared by this process The leather is finished by shaving and scouring part of this work being done at the tannery and the balance at the New York factory as mentioned above May 1906
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