I pulled a book off the "free books" cart at the library, with the intention of taking it apart to show you all how regular case bound hardcovers are made. It didn't quite turn out that way.
First, some terminology. I'll introduce a few more words as we go along.
Text Block - the content pages of a book are first made up into a text block by joining them on one edge, the spine, to create a sort of book but just of the pages of content. Normally pages are joined either purely by gluing the raw edges of paper together, essentially embedding the edges of the pages into a thin block of glue, or the sheets of content are folded, nested together to form quires, and the quires are sewn together along the fold. In this case a sheet may be thought of as a double-size page, which has to be folded to produce a book sized pamphlet-like thing.
Cover - Just what you'd guess it is. The decorative/protective covering for the text block. In a paperback, this is a piece of cardstock, more or less, that wraps around the book. A hardcover uses a more complex structure involving two boards, from and back, and another narrow piece of the board material at the spine the whole thing fasted together and hinged with leather, book cloth, decorative paper, or some combination.
Spine - Again, pretty much what you'd guess. This is the edge of the text block the pages are joined together at, and I will also use it to designate the portion of the cover that goes over that part of the text block.
Endpaper - just inside the front and back covers of a hardcover book, you will find a piece of decorative paper twice the size of a page, half of which is glued to the inside of the cover board, and the other hand of which acts a lot like the first or last page of the text block. It is, however, not part of the text block. Opening the book to that page and inspecting the spine will generally reveal that it is in fact glued to the first (or last) page of the text block, and is not connected to the spine of the text block.
Pastedown - the half of the endpaper which is glued down to the inside of the cover board.
Here's the book, ready for tearing apart. The tool is an Xacto knife, an essential tool and really the only one you need. You use it for cutting, gentle prying, and separating of glued layers of paper. There is a separate device made for the non-cutting jobs, but I haven't got one. Real book nerds have like 10 of them in different sizes.
Another view of the victim. Looks like an ordinary hardback. It's not, which surprised me.
The spine looks perfectly normal, but it's not. The sort of checked blue and white thing you see is a "headband" which used to be a sewn thing, but is now a simple thing you glue on at one point. We'll see it again. The point is, though, it's attached to the text block. The grey-covered board to the right of it is the spine of the cover, as you probably can easily guess. The first point of weirdness I noted is that when the book is opened, there is no sign that the headband is moving separately from the spine of the book. In a normal hardcover, these two move separately, although it may not be completely obvious.
Indeed, it looks very much as if the spine of the text block has somehow become fastened to the spine of the cover. I assumed that this was some sort of slight adhesion due to age or something.
This next picture is just a side note. We're looking at the endpaper here, the pastedown specifically. The text block is in the upper third of the frame, then the hinge is the diagonal crease, and then the pastedown fills the lower 2/3 of the frame.
Notice the slight lines, as if there was some sort of material underneath the pastedown? One at the hinge, and one along the edge. The material, the "mull", does indeed come off the spine of the text block to be glued onto the cover board. That's the excess thickness visible along the spine. Along the other three edges of the pastedown, we're seeing bookcloth folded around the cover board from the exterior. The pastedown covers all. So we know our book has a mull.
Endpapers are just tipped onto the first (and last) pages of the text block. A narrow stripe of glue on the face of the page, at the spine, attaches the end paper to the text block. This is generally step one of disassembling a book, you can just gently tug on the end paper and peel it off the text block.
Normally this is not structural, but occasionally you see very light, or very cheaply made, books with no mull which rely entirely on this tipping-in job to attach the text block to the cover. In a well made book, the mull, or the mull plus some tapes, do this structural job. In these cases, the endpaper is decorative only, and carries no loads.
Continuing to peel it off. We're actually lifting the pastedown a little as well here.
And now the endpaper is entirely free of the text block, here, and the pastedown is lifting off a little as well all the way down.
Here I have torn the endpaper away entirely, much of the pastedown got left behind. The hinge of the book is exposed here, that's the visible crease down the center of the frame.
In this next frame, I've run my Xacto knife gently down the hinge, cutting the text block away from the cover board. The text block, still attached to the other board (indeed, the endpaper at the other end of the book is completely intact in this picture), in on the left, the cover on the right.
I have discovered that the spine of the text block was glued to the spine of the cover, which is extremely weird. The exposed raw cardboard down the center of the frame is where the spine of the cover, a narrow strip of book board, actually delaminated under my knife. A layer or two of book board is still on the text block, which lies off on the left of the frame.
The spine of this book was completely inflexible, being glued down to a quite sturdy chunk of cardboard. Book board is merely a dense and sturdy grade of cardboard, hopefully acid free.
Another view of the same stage of things.
Repeated for the opposite side, the text block is now free of the cover. I cut the endpaper free on the other side, rather than lifting the pastedown, hence the cleaner edge visible right of the cover's spine, as compared with the ragged one left of the cover's spine.
Lifting off the half-endpaper still tipped onto the text block, since I cut it rather than peeling it up previously.
See that stuff in the next picture, that looks like cheesecloth, glued down to the book covers under the pastedowns on each side of the spine? That's the mull. Everyone uses this cheesecloth shit, and it is awful. In this book, it was not merely awful, but irrelevant, and I find its presence quite puzzling.
The loading on the mull involves a lot of shear, under which loading this cheesecloth shit is useless, which is why heavy modern books disintegrate under use. I rebuild them using book cloth, which is basically light canvas, for a mull.
Anyways, this is the stuff we noted underneath the pastedown some number of pictures above.
In the next photo, we see the other part of the mull, glued to to the spine of the text block. Before I got in there with my knife, this part was contiguous with the stuff we saw glued to the covers.
A wide strip of this stuff is glued to the text block, leaving "wings" on each side of the text block. Those wings are glued to the cover boards (as they were in this book). Normally the point of this is to attach the text block to the cover without having to glue the spine of the text block directly to the spine of the cover. Normally, these spine areas move independently, allowing the spine of the text block to flex.
Not for this book!
So how the hell does this book work at all?
It turns out that this book is "backed", which means that the spine of the text block has been formed into a mushroom shape. It's somewhat inelegantly backed, but here it is.
To be honest, I know that backing makes books function better, but I don't quite know why. I think it's because the pages are sort of pre-bent to permit them to open more easily and fully before they begin to ask the spine to flex. In this book the spine cannot flex at all, so backing is pretty much required.
Headband detail. It's just a thingy glued onto each end of the spine of the text block, to cover the exposed end of the spine.
You can see the mull here, again.
By now I am convinced that this thing isn't even a sewn binding. The page count was all wrong, a sewn binding is always a multiple of 4 pages in length. This thing is 208 pages, which is indeed 4 x 52. But what size are the quires? 52 is 13 * 2 * 2. So are we looking at 52 quires here? Or 4?
Neither makes any sense. I wondered if we had variable sized quires, or if I had just miscounted, and moved on. In hindsight, opening the book wide shows no sign of sewing, but then the spine is stiff as hell, so maybe we're just not looking deep enough.
Time to clean up the spine of the text block. I ground off the glue and crap on the spine with coarse sandpaper, and here we have the result.
Detail. No sewing.
This weird thing is perfect bound, like a paperback, but with a crippled spine. Who the hell even DOES that? Even a paperback's spine can flex, because it hasn't been glued to a damned piece of lumber.
Next up, I'll try to find a normal book to take part, to show you mull details, and then maybe I'll show you my interpretation of modern hard binding, which is I think better than any machine bindings available. Although, it's sort of moot, since a good machine binding is certainly good enough for normal use.