English case binding revisited
A style of hardback binding less ordinary
The concept of case binding, meaning that the cover is made off the text-block and attached to it at a later stage, is known world wide, but the details of construction can vary from one country to another. In most European countries the cover consists of a spine stiffener and two boards placed at least 5 mm away from the spine, resulting in a so-called French groove.
In England a case binding is essentially the same thing as a traditional structure: the text-block is rounded and backed at a 90 degree angle and the cover consists of two boards and a spine stiffener, with small gaps in between as no French groove is required. Industrial bookbinding has accustomed us to French grooves, so much so that the absence of the latter makes a book look less ordinary.
Continental and English style case bindings
A frequent drawback
Having spent 3 years at the bench of Shepherds Bookbinders in London, I have made a great deal of English style case bindings. I noticed that, if they usually open very well in the middle, the opening of the board alone often pulls the flyleaf and first leaves of the book with it, which is not only annoying but also makes it feel like something is not quite right and could break sooner or later. I also noticed different styles of backing practiced among the team members, and always thought there might be a link between the latter and the opening qualities of the board, but never actually studied it in depth. I finally found the time to do this and here is what I discovered.
Three styles of backing
As a starting point I identified three styles of backing, based on my observations at Shepherds - flush with the board, higher than the board, and backed to below 90 degrees - which I applied to 3 identical book blocks. Next to this I was also curious about the influence that the hollow may have on the mechanics of the bindings, so for each style of backing I made a version with hollow as well.
NB: for the non-initiated, a hollow is a kind of flat tube made out of paper and applied to the spine of a book to strengthen it. Upon opening one half adheres to the back of the text-block and the other half (usually thicker) sticks to the inside of the cover spine.
1. In all styles there is a certain degree of pulling on the first leaves on opening, but it happens far less with the backing style nr. 2 (shoulder higher than board): the board swings open without tensions and the book block doesn't move at all.
2. Backing at an angle less than 90 degrees doesn't present any advantage - I decide to leave this out of the research altogether.
3. A hollow doesn't seem to have a substantial influence on the board opening - in the above first two scenarios it makes the stress a little worse, whereas in the last it seems to improve it slightly. However in all cases the cover spines are much firmer which makes them more apt to take the weight of the book when opened, so I decide to include a hollow in all further trials.
4. Even though some degree of irregularity due to the gap between the hollow/spine stiffener and board edge is visible on all 3 styles, the first and last variations produce better results. With the second style where the shoulder is higher than the boards, a very pronounced 'mountain' can be seen and felt on either side of the spine, which I would not expect customers to find 'normal'. This is another typical drawback of this structure.
How does it actually work?
Here is a diagram by Arthur Johnson (The Thames and Hudson Manual of Bookbinding, 1978) explaining the reason for higher shoulders:
While this doesn't give much clue about why the pulling is happening, we can guess that the portion of the endleaves proud of the boards provides extra material for the rotation to take place, rather than being forced to happen on one line only as it is the case with a shoulder flush with the boards. To confirm this, I cut my books 20 mm from the bottom edge in order to take a closer look.
What I discovered wasn't as clear as in Johnson's diagrams, but one detail, seemingly unrelated, caught my attention: notice in the image below the slight difference in the endpapers shape (you might need to zoom in):
A minuscule detail indeed! Sometimes that is where the devil lies...So I went back to work to make two new models. My next text blocks were identical to the previous ones, with 16 page signatures, unsupported link-stitched. On one volume I tipped the endpapers about 1 mm further than the signature folds, so that they would hook around the signature folds slightly. The book block was backed flush with the boards, fraynot was applied over the whole thing but headbands and hollow were applied short of the shoulders so they wouldn't raise the shoulder level and also wouldn't be in the way of the hooked part of the endpapers.
On the second volume I tipped the board papers and flyleaves around a folio of white paper, and tipped this end in the conventional way.
In both scenarios the books have a smooth appearance and feel, shoulders level with the boards, and open exceptionally well, both text block and boards.
After many years of letting chance control the final results, I feel that I finally have found a system that allows me to eliminate the two main drawbacks of this structure: the protruding shoulder, and the tension on the endpapers. Unlike my initial guess, the key lies not in the backing style but in the endpaper construction.Whether this way of making English case bindings presents any drawback, time will tell. For the moment, they look and work beautifully and I can't wait to get back to the bench!
Thanks for your attention,
Benjamin Elbel, 22nd of March 2016, Amsterdam
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