Dover Publications: The Quintessential Trade Paperback

Dover Publications reprint of Edith Diehl’s “Bookbinding: Its Background and Technique. I’ve used it heavily since 1988.

A recent piece from the NY Times Magazine, “As Everything Else Changes, My Dover Paperbacks Hold Up”, reminded me how much I love my Dover books. From the perspective of a book conservator, Dover made the best paperbacks I know of, combining physical durability, pleasant tactility and legibility.

The Dover sales pitch, on the back cover of every book, is no lie. “A Dover Edition Designed for Years of Use!  We have made every effort to make this the best book possible. Our paper is opaque, with minimal show-through; it will not discolor or become brittle with age. Pages are sewn in signatures, in the method traditionally used for the best books, and will not drop out, as often happens with paperbacks held together with glue. Books open flat for easy reference. The binding will not crack or split. This is a permanent book.” In addition to being very well made, Dover books were always very reasonably priced. What’s not to like?

The textblock of my “Bookbinding” is in good physical condition, though the surface pH of the leaves is around 4.5. The spine is becoming concave, due to 32 years of very hard use, but the sewing is completely intact. The covering material, consisting of three layers, is also in good condition. There are only a few detached areas on the spine, some delamination, and tension/compression creasing. The spine glue is still surprisingly flexible. Dover books were always well printed, with nicely chosen paper for reproducing illustrations. The book has a pleasing solidity, reminiscent of a phone book. It is not a book that needs careful handling.

At the beginning of my career, this book was read, reread, abused, annotated, and weighted the book open with a bar of steel while I bound my own books following Diehl’s instructions. While the book repair section is quite dated, the binding information is still solid. My students always get a copy of her calm and detailed checklist of what to do in the flurry of covering a full leather book (pp. 208-209).  I like the Dover reprint so much, I’ve never been tempted to buy the original two volume first edition, or the Hacker Art Books reprint.

It is great the Times published a piece about book structure for the general public. As the author notes, the current worldwide instability may drive us to look for more permanent things in our lives, and re-appreciate them. A bit of hope found in a Dover paperback?

Edith Diehl. Bookbinding: Its Background and Technique. New York: Dover Publications, Inc., 1980.  Reprint, orig. 1946.

UPDATED 6 OCT 2020: Corrected title from “… Mass Market Paperback” to “… Trade Paperback” in the title. Thanks to Ann’s comment below!

What do the Sizes of Linen Thread Actually Mean? It’s Complicated.

Some common sizes of linen thread for bookbinding, ranging from 18/6 to 80/3.

Bookbinders likely know that linen thread is classified by a two number system, such as 35/3. And most know that the second number represents the number of threads plied together, and the first number how thick or thin the thread is.  But what does the first number actually refer to?

It turns out that two different systems, an English system and a Metric system that use a similar two part description of size separated by a forward slash. However, these two systems are not the same. Most thread sold by bookbinding supply companies uses the English System.

The English system (aka. Number English, Lea, NeL, Linen Count) is based on how many skeins (of 300 yards) make up one pound in weight. I *think* this means that twelve  12/1 skeins would weigh one pound, or thirty-five 35/1 skeins would weigh one pound. I’m still not sure how adding the plied threads results in the classification. Would a 35/3 thread weigh 3 pounds?

The Metric system (Nm, aka. the Japanese Gunze Count) is based on how many meters of thread weigh one gram.  So I think for a 60/1 thread, 60 meters weighs one gram. It is the same as the English system in that overall, thicker and stronger threads have lower numbers.

Other thread systems include:

Tex — How many grams 1,000 meters of a thread weighs. In this case, the larger the number, the thicker the thread.

Denier — How many grams 9,000 meters of a various thread weights. Again, the larger the number, the thicker the thread. This is useful for very thin threads and microfibers.

Grist — Yards per pound.  For example, a 20/1 linen is 3,000 yards long per pound. Different fibers have different weights.

I’m still not sure what system the Londonderry Linen Lacing Thread in the image above uses. It is labeled only a mysterious “#4”. I love sewing with this thread, though, since it is thick, soft, easy to untwist, tangle free without waxing, and remarkably compressible. It is possible to sew a book naturally packed with it. It consists of five plies, and is roughly equivalent to a 20/5.

If you are wondering what size thread you should use to sew a book, check out my Guide to Swell.

Finally, Colophon Book Arts is a reasonably priced, one stop shop to purchase a wide variety of sewing threads.

Wait, there are more systems  … AARGH!



Cor Knops, of Knops Boekrestauratie in the Netherlands,  kindly sent me these images of some antique thread he owns.


Great name!

These packages contain hanks of thread, and all weight about a pound.  I think the package on the left is 25/3, and on the right 12/3. So if my calculations are correct, the 12/3 should contain 1200 yards of thread, assuming a 12/1 would contain 12 – 300 yard skeins = 3600 yards.  Enough thread for a lot of books in any case!

Don’t Wash … Scour!

Last summer I recorded my investigations into replicating early 19th century book cloth  using XSL pigments. One difficulty was achieving an even coloring, and several commenters indicated I should scour the fabric, rather than just wash it. Finally, I had a little time to try this, and although I haven’t had a chance to do more dying, tests with wheat starch paste have been astounding.

Note all the yellowish junk that came out of the muslin: oils, waxes, and pectic substances.

I boiled 1.5 yards of Springs Creative 45″ unbleached muslin (133 x 72 thread count, .007″ thick, $4.00 a yard) for two hours in a stainless steel pot, using 1 tablespoon of soda ash per 6 cups of water. Since it smells a bit, it is advisable to have a externally vented exhaust hood.  A long stirring stick is necessary, as are rubber gloves.

Keep a close eye on the boiling muslin. I used large pieces of cloth, for future use as covering material. As the water boils, hot areas form bubbles under folded and wrinkled areas. Then when you stir, they get released and the pot bubbles over, or worse, spills on you. I stirred the pot every 15 minutes so that all cloth surfaces were exposed to the scouring, and adjusted the temperature as necessary to keep an even boil.

The scouring raised the pH of the cloth from around 5 to 7, though this was measured with testing strips and is likely not super accurate. Soda ash is around 10 or 11 pH. The scouring removed oils, waxes, and pectic substances. The cotton fibers swelled and softened during the process.

Muslin samples pasted onto Mohawk Superfine. Left: Scoured. Middle: Washed. Right: Untreated. Note the superior adhesion of the scoured sample, skinning the paper during a pull test.

The difference in adhesion between the scoured, washed, and untreated samples is remarkable. All were pasted with Aytex P wheat starch paste onto a piece of Mohawk Superfine, with the same weight during drying.  I testing the adhesive strength by pulling the fabric away from the paper at 180 degrees. The scoured sample delaminated the paper, while the washed sample (hot water, a tiny bit of Seventh Generation Free and Clear detergent, industrial washing machine) and untreated sample released without affecting the surface of the paper. I tried this two more times, and the results were the same. In a separate test using EVA all the samples delaminated the paper.  I’d like to get a push-pull gauge to quantify the adhesion a bit more rigorously. Of course, there may be circumstances where a weaker adhesion is desirable.

But for most book conservation applications — spine linings, board slotting flanges, hinges, sewn stuck-on endbands, covering material — strong adhesion is desirable.