What is Shingling?
What is "shingling," also
referred to as "creep" or "feathering,"
and why should you care? Mastering the concept behind these
arcane terms will infinitely improve your saddle-stitched
books.
Shingling, or creep, refers to the
fact that the trim margin of inner pages of inner signatures
of saddle-stitched books are actually narrower than pages
in outer signatures.
Keep in mind that each inner signature
is nested (or inserted) in each successively outer signature.
In effect, this means that each signature wraps around a
slightly narrower signature. Said differently, each sheet
is nested into a larger bundle (or wraps around a smaller
bundle).
Be aware also that heavier paper stocks
increase the difference between the width of inner and outer
sheets (and signatures). And, the more signatures you nest
one into the other (the longer the book), the more pronounced
is the effect of shingling.
So what? Well, if you have positioned
folios, for instance (or any other repeating visual element)
near the face margin, and you haven't adjusted for creep,
the folios in the center of the book, after the book has
been trimmed, will be closer to the margin than the folios
at the beginning or end of the book. If your margins are
too tight as well, copy can actually be trimmed off completely.
This could be catastrophic.
So what can you do to avoid this? Subtract
1/32" from the face margin (move everything this far
toward the gutter margin) within each successive, interior
signature. Keep each signature internally consistent, but
make this change from signature to signature.
Another little trick for compensating
accurately for creep starts with your obtaining a blank
paper dummy from your printer. Request that this paper dummy
be created with the exact weight and finish of paper you
will use and at the exact page count with the signature
breakdown you will actually print (i.e., the combinations
of 8-page and 16-page signatures). Now, drill a hole in
each corner of the live image area and then disassemble
the paper dummy to see how these holes shift from signature
to signature (and then account for this shift in the electronic
files for the book). As an alternative, use a razor blade
to make a 1/2" cut vertically into the folded paper
dummy about an inch from the saddle-stitched bind-edge.
Again, when you open the pages anddisassemble the paper
dummy, you will see the exact amount you must shift the
margins to account for creep.
Since signature page counts may fluctuate
within a book (from 4- to 8- to 16-page signatures, for
instance), and since paper thickness and finish affect shingling,
ask your printer to check your work if you feel unsure of
the accuracy of your compensation.
For those of you designing perfect-bound
books, there's good news. The pages of a perfect-bound book,
unlike those of a saddle-stitched book, are all the same
width. Therefore, you needn't compensate for shingling when
designing this kind of book.
Watch for Flopped Photos
Most of you will scan your own photos
for most jobs. Scanners are cheap enough and of sufficient
quality for most people to scan their own images for most
applications. However, if you are producing a publication
with large, high-quality photos that must be true to color
(with no variance), you may choose to have your printer
scan and perhaps even color correct your images.
This is the time to check the printer's
proof closely to make sure the image was not inadvertantly
flopped. If your image isprinted--essentially--backwards,
in some cases this may cause no problems. However, if there
is a logo printed backwards in the image, or if there is
a sign in the background with words printed backwards, your
final printed piece will embarrass you. It happens. Printers
make mistakes. So check specifically for this potential
flaw to make sure you avoid it.
For that matter, if you're scanning
a transparency yourself, you may inadvertantly load the
slide backwards and do the same thing. So make one final
check to ensure accuracy.
[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.]