A printing assembly including a support means supporting a rack and adapted to be attached to a drafting straight edge. The rack extends through a head assembly and is engaged by a pinion gear for moving the head assembly along the rack. The head assembly is connected through links to a carriage which supports two longitudinally extending rows of type characters. The head means is moved between a raised position and a lowered position and includes a hammer pin for engaging one of the type characters to cause it to print when in the lowered position. Normally the head means prints the characters in one row but includes a handle on the links interconnecting the head means and the carriage to shift the position of the links so that upon movement of the head means to the lowered position, a character in the other row will be printed.
