Patent Model of a Flatbed Cylinder Perfecting Press: Set-off Web

Cottrell, Calvert B. · ca 1876

This patent model demonstrates an invention for a flatbed cylinder perfecting press which was granted patent number 175036. The patent dealt with perfecting presses in which the first side of a sheet was printed from type on a cylinder, and the second from a flat form. Normally slip sheets were used in such presses. This invention replaced the slip sheets with a length of tympan paper stretched between rollers, a new section being wound out for every impression. The invention was widely adopted.