Abstract: A drill (10) for flexographic plates and negatives includes a table (15) movable in a Y direction under a drill bar (30), and a pin bar (25) movable in an X direction on the table so that negatives can be supported on the table, moved to an appropriate positon underneath the drill bar, and held in place by clamping the table and the pin bar. Drill bar (30) moves up and down and rotates a linear array of hollow spindles (35) holding hollow drill bits (40) for boring a suitable array of holes. The same array bored in the negatives is then bored in a flexographic plate corresponding to each negative, and these are pinned together while the plates are imaged. Drill (10) includes slug rods (32) extending downward through spindles (35) and bits (40) to push out drilled slugs when the drill bar raises. The spindles are preferably rotated by a drive chain (55).

Abstract: A pin bar 10 for mounting flexographic printing plates 25 on print cylinders 20 is formed as an angle bar 11 having two pairs of bearing regions spaced apart on two parallel lines near the bar edges 14 so that the bearing regions can all engage the cylindrical print surface of a print cylinder to align the bar parallel with the axis 21 of the engaged cylinder. Pins 40 for mounting the plate are axially movable in a slot 50 that extends parallel with the lines for the bearing regions. A set screw 45 holds each of the alignment pins 40 in a selected axial position in slot 50, and a clamp on each end of the bar includes a chain 36 that can wrap under a cylinder shaft 24 and be tensioned by a screw 30 and a hand nut 31 for holding bar 10 firmly in position on cylinder 20.