Leather Reback - PC4 Paper

This particular book originally had laced on boards. The board were now detached, but were important to keep. Since the original leather was delaminating from the boards, I decided to remove it and attach it to new boards. 

 

The first step was to clean and line the spine. Then I sewed on end bands, constructed end papers, and cut new boards. I attached the boards and put the book in a finishing press, where I molded a damp strip PC4 paper over the spine. This dried over night.
I was able to remove the original leather from the boards gently with a spatula. I also removed and kept the turn-ins. I glued down and turned in the new PC4 spine piece, infilled the boards, and glued down the original leather and turn-ins. Where sections of the turn-ins were missing, I glued down PC4 strips. I lined the board edges and missing areas with Japanese tissue. Then glued down the end papers, and toned the tissue to match. This was then end result.

Rebinding

These are two batches of rebinds I worked on. I toned some PC4 paper lightly with acrylics and wanted to use it for quarter rebinds.

Missing Board

This particular book was leather bound and missing its back board.

Normally, my first response would be to rebind the book. If the book had any important book plates, I would soak that board in a warm water bath, until the book plates floated off. Then I would reattach them to the new board when dry. However, this book had a nice book plate that was painted with fugitive inks. A water bath would have destroyed it. I  had to find another way to replace the board.

Since the front board was not attached, I used it as a guide to cut a new piece of board (make sure to account for the added thickness of materials at the squares). I sanded and back cornered the new board so it would tight against the shoulder. Then I cut new endpapers for the back cover, and attached them to the text block with paste.
I toned a piece of PC4 paper using and acrylics/methyl cellulose mix, to match the original leather. While that dried, I built up the corners on the remaining board.
I took the new board and covered it with the PC4 paper and put it in the press, between blotters, to dry flat. Since this paper is relatively thick, I also infilled the board with a 10 pt card (after pressing).
Because the original spine was a tight back and was still intact, I couldn't bring the new material around the spine. Therefore, I attached the new board as I would the originals, with Japanese tissue at the hinge and joint.
I attached the boards at the inner hinge first, using a strip of Japanese tissue and wheat starch paste. (This has to be done one at a time. Make sure the paste has ample time to dry). I reinforced this by adding additional tissue to the joint with PVA. I also reconstructed the head caps. I glued out a piece of tissue, overlapping on to both boards, and wrapped it around a piece of cord, the width of the spine and the height of the squares.
Finally, I toned all the tissue to match. This is the end result. (Middle: original leather board, Bottom: new PC4 board).

Leather Reback

On a recent field trip to the book conservation lab at Cornell University, I saw a few leather bound books that were rebacked with new leather (calf). This was interesting for me because most of the leather rebacks were do at Syracuse are repaired with PC4 paper. I decided to go through the stacks and find a good candidate for this treatment. This was the book I found.

My first step was to dye some of the calf leather we had to match. I used J.Hewitt aniline dyes, which start as a powder. You mix the powder with wheat starch paste (powder) and a little water to make a paste, then dilute as needed with boiling water. Dampen the leather with a sponge, then apply the dye. This picture shows the leather before (left) and after (right) dying.

While the leather was drying, I removed the old spine piece (saving the label), and cleaned the spine with methyl cellulose. I had to watch it carefully to the original end bands did not come off with the gunk. I pasted out the spine and lined it with Japanese tissue, which came up on to the end bands for additional support. Then I cut strips of linen, to fit between the cords, and glued them down with PVA. While the spine dried, I lifted the leather and end papers at the spine and corners of the boards. I reattached the boards by gluing the linen spine lining down under the lifted leather.

I pared and pasted out the new leather (one thick coat, let sit for 10 min folded over itself, add another coat) and molded it over the corners and spine. I also made sure to leave enough leather at the head and tail (after turn ins) to construct head and tail caps. I left this to dry over night. 

The next day, I glued down the lifted materials with PVA. I glued out a strip of Mylar, and slid it under the lifted leather, tapped down on it gently, and slid the strip out. This ensures just enough glue gets underneath, and has less risk of the leather darkening. I also pasted out strips of Japanese tissue for the inner hinge. 

While this dried, I worked on the spine label. I found a Morike similar in color to the label, and glued two pieces together. Then I glued the original label to the Morike and toned it to a better match with acrylics. I measured the spine width, and the height between cords, and cut the Morike to size. Then glued it in place with PVA. These are pictures of the end result.

I am going to try the technique on other books in the lab. The biggest problem I faced was building up my corners, which is something I need to work on. Other than that, my color is a little light, so the next time I will add a few additional coats of dye and dab them on with a sponge, to give the leather an aged look. Aside form dying the leather, this process didn't take much longer than a PC4 reback, and I like the end result better. Obviously the materials for this type of repair are more expensive, but I think it is worth it for the right books.

Rebacking Full Leather Bindings

Rebacking is a treatment typically performed when the text block has broken at the joint in the following three ways: where the endpapers fold, where the boards are connected to the text block (linen or mull spine liner in cloth bindings and the cords that lace on boards in leather bindings), and the cover material. Rebacking consists of constructing a new spine piece out of durable/flexible paper, and using it to reattach the text block and boards so the book can function properly.
To illustrate the process with full leather bindings, I selected four dictionaries from the collection at Syracuse which needed rebacking. All front covers were detached from the text block, and about half of the back covers. Spines had split away from the covers and had several bits missing and all the endbands cracked and coming away from the text block. The following images depict this condition.

 

The first step is to clean and reline the spines. I removed the old covers, spines and broken endbands. Using silicon release paper lined boards, I cleaned each spine with methyl cellulose, being mindful of the raised cords. When the spine was clean, I lined the entire spine with Japanese tissue. Since it is necessary for the cords to remain uncovered, I wanted to practice with two main methods of attaching the linen lining. For two books, I cut the linen into strips the exact distance between the cords, and lined each section between cords and at the head/tail. This took much longer, but laid flatter. For the other, I cut one long strip of linen, and then cut out spaces for each cord, which was faster, but bunched and wrinkled by the shoulder. Once the linen was attached I began resewing the endbands. Due to the large size of these books (approximately 18" tall), I had to move from the bench to the board shear to get the right height for sewing.

When the endbands were completed I began preparing the spine pieces. For leather bindings, PC4 paper is used. It is a heavyweight paper, which is toned with methyl cellulose and acrylics. PC4 paper is relatively flexible when damp, but dries rather hard, functioning as the spine and the stiffener. The PC4 paper is cut into strips the length and width of the spine, accounting for turn-ins, and is parred at the edges. In order to fit tightly over the cords, the prepared spine piece must be molded. This is done using a finishing press (with screws along the sides) and cords. The PC4 paper must be dampened and placed in position. When this is done cords are wrapped around the raised cords of the spine, and secured at the screws like so:

While the spine pieces were drying, I worked on lifted the endpapers and leather on the covers. I then began re-attaching the boards to the text blocks via the linen. First I placed a sheet of waste paper and silicon release paper under the linen. Next, I glued out the linen (PVA) and removed the waste sheet. Then I  placed the covers on so the linen would stick to the board where the endpaper was lifted away, and kept the book closed to dry. Once it was dry, I began attaching the PC4 spines.
I began by putting the spine piece in position. I work with the book flat on the bench so the spine piece is weighted down by the text block. I glued out the board underneath the lifted leather (PVA) and continuously pressed down the PC4 paper until it stuck. Then I placed silicon release paper between the PC4 paper and the lifted leather (to prevent moisture from being introduced to the leather too soon), and flipped the book over to dry under the weight of the text block. I did this to all four books, then repeated the process with the other side. Then I glued down the lifted leather (PVA). Once all the spine pieces were attached to both covers, I glued down the head and tail turn-ins. When those had dried, I glued down the lifted endpapers (PVA), and then covered the hinge with a strip of Japanese tissue (paste).
After all the inside hinge repairs were done, I glued the remaining original spine pieces to the new PC4 spine (PVA) and consolidated the leather with Klucel G. Next I repaired the corners and put Japanese paper along the leather at the joint and along the edges of the original spine pieces. I used two different methods for this as well. On two books I used morike (top), which had to be cut to shape with a water pen, but was already a similar color and therefore easier to tone. On the other two I used dry tear strips (bottom), which allowed for fast and easy application, but proved more difficult to tone. Finally, I rubbed some SC 6000 over the joints to add some shine to the toned Japanese tissue and prevent the acrylic from cracking with use (Winter 2009).

 

Recasing

Occasionally in the library, I encounter books with covers so badly damaged it is easier (and cheaper) to recase the text block than to mend the original covers. Recasing is also a treatment option for damaged books that are not especially valuable.
This is an example of a book I recased. It was originally a quarter bound leather, tight backed (fastback), with marble paper covered boards. The paper was torn and faded with dirt and age. The spine had completely delaminated and split off the front board (Top). Delamination at the spine also caused the text block to split (Bottom).

I started by removing the cover. I pressed the sections of the text block together between boards, and cleaned the spine with methyl cellulose to removed the old liner and adhesive. The sewing was cut in several places, so I had to pull the text block apart. I washed and deacidified the sections in filtered water and magnesium bicarbonate [Mg2(CO3)2]. After the pages dried, I repaired damaged areas with heat set tissue, and guarded each section using wheat starch paste and Japanese tissue. I realigned the signatures, resewed the text block, adding dove gray endpapers and lined the spine with Japanese tissue. The addition of materials from guarding caused swell in the spine, so I rounded it to reduce this swell.

I decided to mimic the original case design with a quarter binding in PC4 paper. I cut the boards to fit, attached the PC4 spine and trimmed the PC4 to be even and straight on both covers. Next, I covered the remainder of the boards with book cloth. Then I trimmed the turn-ins, infilled the boards, and attached the text block. After pressing the book with jointing boards, I attached the labels, which were pre-coated with Klucel G to prevent the ink from smearing (Summer 2009).

The above image on the left shows the finished product and the right depicts the stability of the text block after treatment. The below images are additional before and after examples of recased books. These book were bound entirely in book cloth (2008).