A Web Press is Not Always Perfecting
A Quick Tips reader in Belgium
recently brought to my attention an interesting bit of information
on perfecting presses. I stated in a previous article
that all web presses were perfecting. My reader pointed
out that there were exceptions to the rule, which included
such form-presses as the Didde, Drent, Muller Martini, and
others. If a pressman were to print both sides of the web
roll using these presses, he would use “turnbars”
to turn the ribbon of paper over so the opposite side could
be printed. This seems to be an amazing feat when you consider
that the paper runs through the press at between 300 feet/minute
and 3,000 feet/minute. So even though the ribbon of paper
only goes through the press once, unlike some presses that
print both sides of a roll of paper as it travels in a flat
path through the press, these presses print both sides of
the paper at once by actually turning the paper over during
the printing process.
Saddle-Stitch vs. Perfect Binding
When do you decide to perfect
bind a book rather than saddle-stitch it? At what page count
should you switch?
I was told recently that the rule of
thumb is 96 pages plus cover. Like most rules, this one
has many exceptions. Why? Because there are several variables
in any printed piece. A 120-page magazine printed on a heatset
web, for instance, on 45# text stock might be just fine.
The same book printed sheetfed on 60# white offset would
be bulky and not lie flat when closed or open. Worse yet,
the stitches might not hold, and the pages in the center
could fall out.
In making this decision, consider the
weight of the paper and its surface texture (a 60# gloss
sheet would be thinner than a 60# uncoated offset sheet,
so more pages would comprise the same thickness, caliper,
Other mitigating factors include time.
Higher page counts will slow the stitching equipment down
and or may require multiple passes on the stitcher. For
example, if your publication is 96 pages plus cover plus
a cover wrap (six 16-page signatures, a cover, and a cover
wrap), you will have just enough elements for a seven-pocket
stitcher with an extra cover pocket. Add an 8-page signature,
and you will need a double-pass on the stitcher (there are
only seven stations on the stitcher so you will need to
pre-collate some signatures). Does your publication schedule
have time for this, or will it cause your job to miss the
delivery or mail deadline?
Higher page counts may also put a nick
in the top and bottom of the pages at the bind edge, and
the pages in the center of the book might not be adequately
held in by the staples. Pages could fall out when your reader
least expects it.
Ask an expert. Your printer can suggest
the proper point at which to shift from saddle-stitching
to perfect binding, based on your paper stock, and he can
even provide a paper dummy of both options. This way you
can see what the final product will look like before you
commit to saddle-stitching or perfect binding.
A few years ago I wrote a Quick Tips
article that included a description of various coating options,
such as varnish and lamination. I even mentioned lay-flat
lamination. But I think this bears repeating and describing
in more detail.
Lamination can be a liquid that dries
to a tough gloss or dull surface, or it can be a film. Both
adhere to the cover of a book, for instance, to protect
it and give a sheen or a muted effect (gloss or dull, or
even satin, an “in-between” look).
But over time moisture in the air will
seep into the paper fibers on the inside front and inside
back covers of this book, causing the paper to expand. The
laminated side, unfortunately, is not porous and will not
absorb the water and air, so the uncoated side will bow
outward, and the coated side will not, making the paper
cover curl. This is unsightly.
How can you avoid this? You can use
lay-flat laminate. Lay-flat laminate either has grooves
that allow the coating to expand and contract to prevent
curling, or it is made of a porous material such as nylon,
which is permeable by water and air. Such a porous coating
allows the outside covers and inside covers to maintain
an equilibrium. This avoids curling.
A Fine Point of Style
What is the difference between the
words “register” and “registration”?
When you say two (or four or however many) colors are “in
register” on a press sheet, you mean that they are
properly aligned relative to one another. When the color
is “out of register,” the images and type look
blurry. When the colors are “in register,” the
images and type look crisp and in focus.
on the other hand, refers to signing up for something, like
a university class. It is a fine point of wording, but as
with any language, when you speak with a printer and use
his language correctly, it will make communication easier.
So instead of referring to “good registration,”
say, “The colors are in register.”
[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.]