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Subject: Excel binding

Excel binding

From: Pete Jermann <pjermann>
Date: Friday, April 5, 1991
I would like to offer several reflections concerning the problems Jan
Merrill-Oldham encountered with Excel bindings.  Since I have no
experience with Excel bindings (is this the product of a specific
bindery or a generic type of binding?)  but much experience with a
variety of bindings, including double fan adhesive bindings, these are
general reflections applicable to a variety of bindings.

A text block falls forward in its case not because of inadequate spine
lining but because it has some place to fall.  Tradition insists that
hardbound, cased books have a square (the part of the case extending
beyond the edges of the textblock) at the bottom of the book. This
square puts distance between the textblock and the shelf on which the
book sits. Gravity pulls the textblock toward the shelf thereby causing
a deformation of the spine and the hinges.  The addition of spine
linings stiffens the spine and the hinge area by creating a laminated
structure which resists this deformation.  However, the same structure
also resists the movement we expect in the spine when we use the book.

There are two answers to this problem.  We can modify the structure on
the spine to give us the best compromise between shelf durability and
useability or we can eliminate the squares at the bottom of the case,
thereby eliminating the stress that caused the problem to begin with.
Elimination of the squares is the easier of the two and produces a book
whose condition on the shelf is relaxed rather than perpetually
stressed. Such is already the normal state of our everyday paperback
book.  Though paperbacks have their own problems they do not fall out of
their cases on the shelf nor does proper shelving lead to deformation of
the spine and hinge areas.

The "problem" Jan encountered with the book's opening so that the two
parts of the block actually touch rather than the spine opening into an
arc may or may not be a problem.   Whether this creates an area of
stress depends on the construction of the spine and the quality of the
materials used.  Traditional lining (super and kraft paper) creates a
laminate on the spine that leverages the tension on the super when the
book is opened.  The more heavily the spine is lined the greater this
tension.  Should the spine of such a book be forced open into a severe
inverted "V" either the super, the paper liner or the leaf attachment
will be damaged.  Usually the paper liner delaminates at the point of
stress.

On the other hand, if we use a single, strong, thin cloth liner with no
additional layers we greatly reduce or eliminate the stress usually
associated with an inverted "V" opening.  What we have is a single cloth
folded back on itself.  The stress question becomes one of the cloth's
fold endurance rather than its tensile strength.  The primary tension on
the joint would then be the unleveraged weight of the part of the
textblock which hangs in suspension from the opposite part.  This
tension would be much less then the leveraged tension caused by a
laminated spine.  Such a thinly lined spine can produce a highly usable
and durable book if it is properly cased.  A proper case would provide
for increased movement of the spine and allow the text block to rest on
the shelf rather than hang from its case.

The reflections above derive from experience and research in progress
concerning book structures.  I am currently examining book structures,
the assumptions underlying these structures, and whether these
assumptions should be re-evaluated in light of modern materials and
methods. Hopefully, this research will achieve some sort of formal
presentation in the future.  Any suggestions, knowledge of similar or
related research, ideas or questions would be appreciated.

On the lighter side I close with the following tale illustrating my
assumption that life as a book is a pain:


                          The Agony and the Agony
                                     or
                            Misery in the Stacks

                              by Pete Jermann

It was uncomfortable sitting on the shelf all day, day in and day out,
year in and year out.  Libra's shoulders tensed and her back ached. Oh,
if she could just put her whole foot down she could relax.  Rather she
hung between her boards, reaching out with her foredge toe, hoping to
take the tension from her shoulders, only to pull her back out of shape.
How she longed to lie down and rest.

Then one day a patron came for her services.  Libra looked forward to a
brief moment of comfort away from her prison. Instead the patron rudely
grabbed her headcap and yanked her from the shelf.  Her scream echoed in
the silence, but did not penetrate it.  The patron heard nothing. Her
pain subsided, replaced by the assuring warmth of his hand embracing her
spine, couching it and supporting it.  Libra laid back and took joy in
the experience. Her shoulders relaxed, her back eased back into its
normal shape.

The patron laid her on a table, where, at last, she found total repose.
"This must be heaven," mused Libra.  "My life should be like this."

Ecstasy, however, is usually shortlived and Libra was no exception. The
patron opened one board, exposing her endsheets to the air and the
light. Her shoulder tightened and pulled on her flyleaf and title page.
After searching her table of contents, the patron turned to chapter ten.
Libra felt a searing pain in her spine as her paper liner compressed and
her super pulled taut.   Again she cried into the unhearing silence. The
pain was relentless.  The spine liner on her cloth case pushed out on
her shoulders as her pages tried to lay flat.  Her super, wanting
nothing more than to go with her pages, was pulled tight by her case and
pushed into high tension by her paper spine liner.  The paper liner
fought its own battle against creasing and delamination as it resisted
the compression forced on it by Libra's super and pages.  Her pages,
wanting nothing more than to lie flat, pulled at her super, which fought
her paper liner. Together they all pulled on her shoulders.

Heaven became hell.  Libra wished she was back on the shelf.

    Future installments:
        Libra Visits the Xerox Machine
        Libra Meets the Tape Mender
        Libra Becomes a Discard

                                  ***
                  Conservation DistList Instance 4:54
                  Distributed: Friday, April 12, 1991
                        Message Id: cdl-4-54-004
                                  ***
Received on Friday, 5 April, 1991

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