MILL.
The business of the Calenderer and Hotpresser in so many respects resembles part of that already described as preceding the printing of calico, that only a brief notice of it will be necessary. The singeing and bleaching of the cotton has been explained, and calendering is the name generally applied in the manufacturing districts to the processes of smoothing, dressing, and glazing cotton and linen goods; the object being either to prepare them for the operations of the calico printer, or to impart the last finish to the goods before they are folded and packed for the market. The earlier calenders, or calendering machines, closely resembled a common mangle in their action, but were very large and heavy, and worked by a horse-wheel or other sufficient power, but the process was greatly improved by the invention of a machine in which the pressure is produced between rollers, instead of between rollers and flat surfaces, and in which consequently the alternating movement is got rid of, and also it is easier to give a uniform and equal pressure.
Singeing Cotton Goods before Calendering. Iron Plate. Roller. Windlass. Scissors. Tongs.
Embossed Roller for Machine Printing. Presses.
The rollers or cylinders were formerly made of wood; they are now usually of paper or cast iron. The paper cylinders are formed by packing a great number of circular pieces of stout pasteboard upon an iron axis, and compressing them very tightly by means of iron bolts passed through them, acting upon circular end-plates of cast iron. The surface is brought to a perfectly even and polished state by turning in a lathe. Iron rollers are made hollow and when necessary heated from the inside. When a glazed or polished surface is required on the goods to be calendered, mechanism is employed to cause two adjacent rollers to revolve with different velocities, so as to produce a rubbing action.
Printing Press. Chair with Rollers. Tin Block.