Folding Bookbinder Supplied Folio with Bone Folder

This entry is part 4 of 20 in the series The Art of Bookbinding (Joseph W. Zaehnsdorf, 3rd Edt, 1897)


It is generally the first thing the binder has to do with a book. The sheets are either supplied by the binders or printer (mostly the printer); should the amateur wish to have his books in sheets, he may generally get them by asking his bookseller for them. It is necessary that they be carefully folded, for unless they are perfectly even, it is impossible that the margins (the blank space round the print) can be uniform when the book is cut. Where the margin is small, as in very small prayer books, a very great risk of cutting in the print in incurred; besides, it is rather annoying to see a book which has the folio or paging on one leaf nearly at the top, and on the next, the print touching the bottom; to remedy such an evil, the printer having done his duty by placing his margins quite true, it remains with the binder to perfect and bring the sheet into proper form by folding. The best bound book may be spoilt by having the sheets badly folded, and the binders is perfectly justified in rejecting any sheets that may be badly printed, that is, not in register. The sheets are laid upon a table with the signatures (the letters or numbers that are at the foot of the first page of each sheet when folded) facing downwards on the left hand side. A folding-stick / bone folder is held in the right hand, and the sheet is brought over from right to left, the folios being carefully placed together; if the paper is held up to the light, and is not too thick, it can be easily seen through. Holding the two together and laying them on the table the folder is drawn across e sheet, creasing the centre; then, holding the sheet down with the folder on the line to be creased, the top part is brought over and downwards till the folios or the bottom of the letterpress or print is again even. The folder is then drawn across, and so by bringing each folio together the sheet is completed. The process is extremely simple. The octavo sheet is generally folded into 4 folds, thus giving 8 leaves or 16 pages; a quarto, into 2, giving 4 leaves or 8 pages, and the sheets properly folded, will have their signatures outside at the foot of the first page. If the signature is not on the outside, one may be certain that the sheet has been wrongly folded. I say generally; at one time the water or wire mark on the paper and the number of folds gave the size of the book. There are numerous other sizes, but it is not necessary to give them all; the process of folding is in nearly all cases the same; here are however, a few of the sizes given in inches.

Follscap 8vo.6 5/8 x 4 1/8
Demy 12mo.7 3/8 x 4 3/8
Crown 8vo.7 ½ x 5
Post 8vo.8 x 5
Demy 8vo.9 x 5 ½
Medium 8vo.9 5/8 x 5 ¾
Small Royal 8vo.10 ½ x 6 ¼
Large Royal 8vo.10 ½ x 6 ¾
Imperial 8vo.11 x 7 ½
Demy 4to.11 x 9
Medium 4to.11 ¾ x 9 5/8
Royal 4to.12 ½ x 10
Imperial 4to.15 x 11
Crown Folio.15 x 10
Demy Folio.18 x 11

As a final caution, the first and last sheets must be carefully examined; very often the sheet has to be cut up or divided, and the leaf or leaves placed in various positions in the book. It is also advisable to cut the head of the sheets, using the folding-stick, cutting just beyond the back or middle old; this prevents the sheet running into a side crease when pressing or rolling. Should such a crease occur the leaf or sheet must be damped by placing it between wet paper and subjecting it to pressure; no other method is likely to erase the break.


With regard to books that have been issued in numbers, they must be pulled to pieces or divided. The parts being arranged in consecutive order, so that not so much difficulty will be felt in collating the sheets, the outside wrapper is torn away, and each sheet pulled singly from its neighbor, care being taken to see if an thread used in sewing is in the centre of the sheet at the back; if so, it must be cut with a knife or it will tear the paper. As the sheets are pulled they must be laid on the left hand side, each sheet being placed face downwards; should they be placed face upwards the first sheet will be the last and the whole will require rearranging. All advertisements may be placed away from the sheets into a pile; these will be found very handy for lining boards, pasting on, or as waste. The title and contents will generally be found in the last part; place them in their proper places. The sheets must now be refolded, if improperly folded in the first instance. Turn the whole pile (or book now) over, and again go through each sheet; alter by refolding any sheet that may require it. Very often the sheets are already cut, and in this case the section must be dissected and each leaf refolded and reinserted in proper sequence, and placed carefully head-line to head-line. Great care must be exercised, as the previous creasings render the paper liable to be torn in the process. Books that have been bound and cut would b rendered often worse by refolding, and as a general rule they are left alone. Bound books are pulled to pieces in the same manner, always taking care that the thread is cut or loose before tearing the sheet away; should trouble arise through the glue, etc., not coming away easily.

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