AB Dick direct feed presses pick sheets further back from the lead edge than do most other presses.
As a result, short-grain, news-print, and other light-weight/grain-less stocks have a tendency to turn under or 'droop' down when picked up past sheet levelers/separators causing paper jams.
This is a result of a 'limp', or weak/slow flip response to the force of the sheet levelers/separators.
A simple and cost effective way to 'strengthen' the lead-edges' flip strength/responce to the separators and improve feeding at high production speeds is to shim 'down' everyother sucker tube to create a slight 'undulating' or wave effect in the sheets' lead-edge.
You can purchase 5/16" exterior Truarc Retainers from a hardware, auto parts, or machinists supply store for a few pennies each and install them at the top end (below threads and against shoulder) of everyother sucker tube.
These retainers are only .015" thick (about the thickness of 3 sheets of 20-lb bond) and will cause a slight wave in the leadedge of the sheets so that the will become stiffer/stronger to resist the downward force of the levelers/separators and feed 'straighter' into the nip of the forewarding rollers.
