Scoring is the term that refers to the process in which a crease is applied to paper stocks and other substrates. The crease is most often used for allowing stocks to be folded easily for a variety of purposes. The applications in which scoring is necessary are numerous. Consider the following examples:

• The cover of a publication becomes much easier to fold when it is scored first.
  
  
• Several locations on a document can be scored to allow it to be folded into a specific size so that it can be inserted easily into an envelope.
  
  
• Shipping cartons are assembled quickly when the heavy corrugated stock, of which they are constructed, is scored to allow for easy folding.

Scores can be applied to paper stocks and other substrates either while the job is being printed (online) or they can be applied before or after the job is printed (off-line). There are many types of conventional offset presses that are capable of applying a score online and some digital press manufacturers offer attachments that can perform a number of online finishing processes, including scoring. Many types of off-line scoring equipment are available as well. Scores can be applied to paper either parallel to the grain (paper fibers) of the paper or perpendicular to the grain. Parallel and perpendicular scores can be applied at the same time and both types of scores can be applied as full scores (the full length or width of the printed piece) or as partial scores (scores that are not the full length or width of the document). Additionally, a combination of full and partial scores can be applied to the paper stock depending on the capabilities of the equipment used.

Online Scoring

Scoring Parallel to the Grain

Long grain paper is most often used for printing. Long grain refers to paper fibers that are parallel to the longest dimension of the paper. Because this is also the dimension of the paper that is parallel with its travel through the press, any score that is applied parallel to the grain would also be parallel to the direction the paper travels through the press.

A small metal wheel is most often used for applying a parallel score. The scoring wheel has a blunt edge, which squeezes the paper fibers in a concentrated area. The blunt edge of the scoring 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.

Scoring Perpendicular to the Grain

For scores that must be applied perpendicular to the grain and/or to the direction the paper travels through the press, steel scoring rules are used. The steel rules are inserted into slots in the cylinders of the press, which allows the rules to stamp the score into the paper as the press 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 supplier to learn of the possible limitations.

Off-line Scoring

There are occasions when scores are added as an off-line process, before or after the product has been printed. Generally, products that have a score applied after printing consist of smaller quantities and have been printed on sheet-fed presses. Larger quantities are more economical to print and score in one operation using equipment such as a conventional web-fed offset press that is equipped for the application of scores or a digital press with finishing attachments.

Scoring with Off-line Rotary Equipment

Many of products that are scored off-line are sent through rotary equipment that can apply only full-length scores. Score wheels, similar to those used for online scoring, are used on the off-line equipment. The scoring wheels apply full scores either parallel or perpendicular to the grain of the paper, depending on the direction the paper is sent through the equipment. It is important to remember that long grain paper is easier to feed into the equipment than short grain paper.

When both parallel and perpendicular scores are required, the paper is sent through the equipment twice. To help save time, some products can be manufactured with several printed copies on one large sheet so that when the sheet is sent through the scoring equipment, the scores are applied to all of the copies on the large sheet at the same time. The sheets are then cut into individual finished pieces. The only drawback of this technique is that multiple documents can be damage at one time if there is a feeding problem or if the score is not applied in the correct position.

Scoring Off-line with Flatbed Equipment

Scores can also be applied with flatbed equipment in much the same way that perforations are applied. The scores are pressed into the paper with the use of special scoring rules. If adjusted properly, the flatbed equipment can apply a score without cutting through the paper.

Prescored Paper for Digitally Printed Applications

Some paper is scored before it is printed. The print supplier might produce their own prescored paper or they can purchase it from a converter. This type of paper is especially useful for digitally printed applications that require a score or scores in standard positions on the paper, such as for documents printed on 8½ x 11 sheets that must be folded for insertion into a #10 envelope.

An Application in which the Paper Was Prescored (and Preperfed) Before Printing

The following suggestions may improve the quality of the score and/or the ease in which the score is applied to the stock.

• The quality of a score is often affected by the grade and weight of the paper. It may be difficult to achieve a good score on thinner stock, such as 20 lb. bond. A score on thin stock is often quite difficult to detect, while a score on stock that is much heavier, such as 110 lb. index, will be much more pronounced. The lighter paper is also more difficult to score properly, because there is less tolerance in the equipment settings required to achieve a proper score on thin stock. Inaccurate equipment settings are more forgiving on thicker stock.
  
  
• The settings used with the scoring equipment will affect the quality of the score. If too little pressure is used when applying the scores, the result may be scores that do not function properly (for folding), if at all. If too much pressure is used, scoring wheels and rules may actually cut the paper instead of scoring it.
  
  
• The paper grain direction has much to do with the quality of the score. Scores that are applied parallel to the grain of the paper will score much more cleanly because the grain (paper fibers) is running in the same basic direction as the score. Very few of the fibers provide any resistance to the scoring action, which results in a high quality score.
  
  
• When a score is applied perpendicular to the grain of the paper, the resulting score may have a ragged appearance. The ragged score is the result of all of the fibers (in the area where the score is applied) being scored at one time, which creates resistance to the scoring action. The ragged appearance is especially noticeable when scoring heavy stocks. Refer to the illustration below.