GB1045877A - Improvements in blanking dies - Google Patents

Abstract

1,045,877. Making dies. WILLIAM CROSLAND Ltd. Oct. 1, 1963 [Aug. 4, 1962], No. 30101/62. Headings B3A. [Also in Division B4] A method of making a die comprises the steps of locating and securing a template and guide pins on a first base-plate, locating guide-pin bushes on the guide-pins, locating a frame on the base-plate around the template and bushes, pouring plastic material into the area defined by the frame and template and curing it, removing the frame, plastic, template and guide bushes together, and using the template as a guide sawing therearound to remove a core of plastic material, reducing the thickness of the core, locating steel rule inserts in the aperture so formed in the plastic material, wedging the rules by inserting the reduced core and mounting the die so formed on a second base-plate. A male die part is produced by making a template 10 of tool-steel which is secured to a base-plate 12 by bolts 13, Fig. 1 (not shown). Guide pins 14 are also secured to the base-plate. To produce the female die half a rectangular frame 15, Fig. 2 (not shown), is located on the baseplate surrounding the template and guide-pins, and phosphor bronze bushes 16 are placed on the guide-pins. A piece of high density wood 17 which is larger than the template is marked with the shape of the template, which is then removed from the base-plate, and in its place is secured the wood with the marked area accurately in the position formerly occupied by the template. A plastic material is then poured into the space between the frame 15 and the wood 17, and is cured, so that the frame 15, wood 17 and bushes 16 are held together, and the assembly is removed from the base-plate 12. The wood 17 is now sawn to remove therefrom a core whose shape corresponds to the shape of the template 10, the thickness of the core is reduced, the aperture formed in the wood is lined with steel rule 19 and the reduced thickness core 17a is replaced to hold the rule in position. The female die part so formed is mounted on a base-plate 20. The template 10 is re-attached to the base-plate 12 to form the male die part. Ejection rubbers 21 are mounted on the core 17a and on the base-plate 12.