Printing & Design Tips: DECEMBER 2007, #77

What Is Runnability?

If you want to be really knowledgeable when you talk to your printer, learn this term. “Runnability” refers to the ability of a press sheet to handle the rigors of the printing process (speed, temperature, etc.). Can the sheet run through a printer’s presses without causing problems such as tearing, wrinkling, picking (losing fibers), and being dimensionally unstable (stretching in various directions rather than keeping its form as a rectanglar sheet)? Will it hold ink on the paper’s surface (or absorb it into the paper’s fibers) consistently and uniformly? A runnable sheet basically does not cause your printer headaches. A printing sheet might be smooth and attractive in the paper swatch book, but if it isn’t a runnable sheet, if it makes your printer need to slow down the presses to get a quality printed product, if it stretches or tears, and causes problems in keeping colors in register, it’s useless.

What Does Machineable Mean?

I recently had a printer bid on a job that included a belly-band (an offset printed paper wrapper attached around a magazine). For 32,000 copies of the magazine, the price was approximately $1.00 per book; for the wrapper, the cost to affix the band around the magazine (excluding printing the wrap) came to almost $.31 per book. Why? Affixing the belly-band was hand-work, which is, just as it implies, work by hand. The hand-work alone would take 160 hours (divided by however many people would help).

Since the ad that would go on the belly-band could not be priced at a level that would recapture the expense of printing and affixing the belly-band (and since no local vendor could do the job on their equipment), alternatives were sought.

One alternative was a cover wrap that would cover the back of the magazine and then cross the front of the magazine as a diagonal sheet (basically a triangle adorning half the front cover of the magazine). This, I was told, would be “machineable” and therefore far less expensive ($.06 per unit).

This is an object lesson in the difference between a machineable process and hand-work. Ask your printer early in the process whether what you want to do is machineable (can be done on press or finishing equipment) or whether it is hand-work. You will avoid an unpleasant surprise when the bill arrives.

What is the Difference Between Embossing, Debossing, and Blind Embossing?

First of all, embossing is a finishing technique whereby an image (logo, type, etc.) is pressed into the printing paper using a die. The resulting image is embossed if it rises above the paper level and debossed if it sinks below the paper level.

Often ink is printed on the sheet, or foil is attached to the sheet with heat and pressure, prior to the embossing. Therefore, the embossed image or type sticks out slightly from the printing or foil on the sheet. Blind embossing, on the other hand, uses no ink or foil. The image is merely pressed into the paper. An example of this technique totally unrelated to printing is the raised Notary Public stamp pressed into a legal document.

What is Scoring?

Scoring is not related to baseball or dating when it refers to the printing operation whereby a steel rule is pressed into the paper stock to “get the fold started,” if you will. Attempting to fold a sheet, particularly a sheet of cover stock printing paper, and especially when folding against the grain (counter the direction in which the fibers in a sheet of paper run), will result in cracking and an uneven fold. When the paper is scored with a steel rule, it will fold evenly without cracking. It is also prudent to score a sheet when the fold will cross a heavily inked portion of the printed piece.

A litho score is done on press during the printing process using a rule attached to the impression cylinder. Another way to score a sheet is on a letterpress (a relief--rather than offset--press). Either way, this adds cost to your job (a few hundred dollars per multiple of several thousand copies). But it is money worth spending. Usually you can get away without scoring a text sheet, but a folded cover sheet really does need to be scored.


[Steven Waxman is a printing consultant. He teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.]