Trish Witkowski is Chief Folding Fanatic at the online community foldfactory.com. She holds a bachelor of fine arts degree in graphic design and a master of science degree in Graphic Arts Publishing from Rochester Institute of Technology's School of Printing Management and Sciences (now the School of Print Media).
An award-winning designer, Trish held the position of creative director for a Baltimore-based agency for six years, and has taught design and desktop publishing at the college level. She has a specialized expertise in the area of folding and is the creator of the FOLDRite™ system, a 2004 GATF InterTech™ Technology Award winner.
Trish frequently publishes articles for graphic arts industry publications, and has written three books on the topic of folding: A Field Guide to Folding, Folding for the Graphic Arts: A Teacher's Handbook, and FOLD: The Professional's Guide to Folding.
Technifold has implemented a new, low-tech twist on the auto feeder that delivers the next best thing to an air-fed mechanism—all at a fraction of the cost.
The classic configuration of a friction feeder consists of a pair of rollers, usually rubber, one fixed and one turning which will separate and feed a small pile or stream of sheets into any number of printing or print finishing machines (see image 1). This means a tremendous amount of pressure is placed on a small surface area of the sheet at a single point of contact. The gap between rollers must be tight enough to prevent a double sheet, but with enough pressure to drive the sheet through this tight spot, which may require frequent adjustments.
This style of feeder is known for marking coated sheets and often requires frequent cleaning to remove ink and dust buildup. The advantages, however, are that it’s fast, simple to manufacture and inexpensive—no air pumps or high-tech controls are needed for a basic version.
What’s exciting about the 2-Stage Auto Feeder (see image 2) found on Technifold’s Speedcreaser machine, is that a clever engineering trick has nearly eliminated the negatives by splitting up the workload into two sets of rollers. Starting with a fanned-out lift of sheets, the “pre-feed” roller gently separates and advances the top sheets forward. The final infeed rollers drive it into the machine and prevent double sheets from entering.
With a wider and softer pre-feed roller, the pressure needed to move the sheet is distributed over a much larger surface area. When the sheet hits the final infeed roller it is already in motion, so the infeed roller needs to exert very little force to move the sheet into the machine. Typically, the pressure setting here is a very light drag, (or even no drag) as opposed to the high drag commonly used in single-stage versions.
The end result is less buildup of ink and residue, virtually no marking or scuffing, and no need to mess around with pressure adjustments. An added benefit is that two points of contact with the sheet improves register by eliminating the tendency for the sheet to twist around a single pressure point. Cool stuff.
Here’s a video of the auto feeder in action:
For questions and to learn more about Technifold’s Speedcreaser machine, please contact Andre Palko at email@example.com