Paper Folders Info

The FD 380 Document Folder from Formax is a fully automatic system designed for churches, schools, or businesses that demand a quick and easy setup. Six common folds are preset for 11-, 14-, and 17-inch paper (international sizes A3, B4, A4, B5, A5, and B6) and can be activated with the touch of a button. Additionally, up to nine custom folds can be preprogrammed and stored in memory. All settings are made via a centrally located control panel and LCD. The device has a telescoping outfeed stacker that holds 500 folded documents, a dedicated multisheet feeder, and the AutoBatch batch counting system that allows operators to key in a predetermined number of sheets to be pulled into sets with a programmed delay between each set.

The 256 LS semiautomatic friction folder is the latest addition to MBM Corp.'s product line. The unit's "Light Set" feature makes it easy to set up and run, and its self-setting exit rollers for standard folds (adjustable for custom) ensure smooth |ejection of folded paper. With a speed of up to 15,000 sheets per hour (single fold, 8 1/2 X 11 inches), the 256 LS semiautomatic folder handles paper sizes ranging from 3 X 5 inches to 11 X 17 inches, in weights from 15 to 80 pounds.

Paper Scoring
Scoring is the term applied to the process that places a crease in paper stocks and other substrates allowing the material to be folded. A score may be used to crease the cover of a publication, provide areas for folding a document allowing insertion into an envelope, create heavy creases in shipping cartons to allow easy assembly of the carton, and numerous other applications.

Parallel Scoring
When a score must be applied parallel to the direction that the stock travels through the printing press, a steel scoring wheel is used. As the stock travels through the press, the scoring wheel applies pressure on the stock in the area where the score is desired. The scoring wheel has a flattened edge, which squeezes the paper fibers in a concentrated area and thereby creating the score in the stock. The flattened edge of the score wheel prevents the substrate from being cut rather than scored. Scoring wheels are available in various widths to produce narrow or wide scores on the substrate. Multiple parallel scores can be applied at the same time. Since the printing and scoring of the substrate are accomplished in one operation, considerable savings in labor and cost can be achieved than if the scoring was performed as an offline operation.

Perpendicular Scoring
For scores that must be perpendicular to the direction the paper travels through the printing press, steel scoring rules are used. The steel rules are inserted into cylinders on the press, which allow the rules to stamp the score into the paper as the cylinders revolve. Like scoring wheels, the rule edges are flattened to allow for proper scoring and prevent the scoring rule from cutting the substrate. Compared with parallel scoring, there are usually more limitations as to the number and placement of perpendicular scores, so it is best to consult the print provider to learn of the possible limitations.

Paper Grain

The paper's grain can be one of the most important aspects in acheiving a perfect fold. The direction of the grain has much to do with the overall quality of the fold. Paper that is folded parallel with the grain of the paper will fold much more cleanly, resulting in a crisp, straight fold. Parallel grain produces a much cleaner fold because the paper fibers (grain) are running in the same basic direction as the fold. Only a few of the fibers run in the opposite direction and are able to provide any resistance to the folding mechanism, thus resulting in a precise, high quality fold.

When a fold is applied perpendicular to the grain of the paper, the resulting fold may have a ragged appearance. Perpendicular grain produces a ragged fold because all of the fibers are folded at one time creating resistance to the folding action. The ragged appearance of the fold is especially noticeable when folding heavier stocks of paper. More fiber results in more resistence, and lower quality folds.