21st July 2013
Hawthorn Baker Ltd launched the new Cornerstone Mixed Forme Base in April 1956.
Hawthorn Baker Ltd launched the new Cornerstone Mixed Forme Base in April 1956. It was introduced following the demands of a large number of printers who had installed electronic engraving machines but who had found that the thin plastic plates caused mounting problems. However, the same problems frequently also happened when working with all sorts of original plates. In order to address this problem, the new base was made in a standard height of 0.849 inch, although other heights could be supplied. The new mixed forme mounting base, like all other Cornerstone lightweight furniture, was made out of duralumin [an alloy of aluminum (90%) copper (4%), magnesium (0.5%-1%), and manganese (less than l%)] that was a rigid extrusion capable of withstanding great pressure both during lock-up and impression. The Cornerstone Mixed Forme Base was made in 13 lengths and 6 widths, and all the sides were perfectly vertical and the angles were absolutely 90 degrees. Each piece was anodised to give total protection and marked with body size and height in a recess on the side of the mount. The height of 0.849 inch allowed for mounting standard original plates 0.064 inch thick with the double-sided adhesive ‘Duplophan’. This had a thickness of 0.006 inch, or 0.005 inch under impression and thus gave the correct printing height.