How to Hand-Sew a Book
A workbench reference for folding, sewing and casing a text block by hand, with the measurements each step depends on.
Not a bindery, a shop or a course: nothing here is sold, booked or made to order, and no binding services are offered.
Divide the page count by four — that is the sheet count — then group the sheets into signatures of five to ten.
One folded sheet carries four pages, two on each side. A 160-page text block is therefore forty folded sheets, and the standard groupings are eight signatures of five sheets or four signatures of ten. Both sew well; the choice is a trade-off, not a rule.
Signatures of five fold flatter and put less paper at each station, so the thread pulls up snug without tearing the fold. Signatures of ten halve the number of kettle stitches and speed the sewing, but each fold is thicker and the spine swells more per section.
Whatever the grouping, mark the stations the same way on every signature: kettle stitches 3–4 mm in from head and tail, and the tape stations spaced to match the supports — 30–40 mm apart on a block this size.
Waxed 18/3 linen thread on four linen tapes — or 2–3 mm cords — is the standard build for a block of this size.
Standard sewing thread for a hand-sewn block is 18/3 linen, about 0.6–0.7 mm thick. Run it through beeswax two or three times before the first stitch: waxing stiffens the twist, lets the thread lock against itself at the kettle, and keeps it from shredding on the paper.
A 160-page block uses roughly 15–20 m of thread. Measure and wax the full length before you start; joining mid-seam leaves a knot inside the fold, and knots are what make spines lumpy.
The supports give the thread something to climb around. Four linen tapes, or linen cords 2–3 mm in diameter, spaced 30–40 mm apart, carry a block of this weight; the thread passes out of each station, around the support, and back in.
| Material or step | Working figure | What it controls |
|---|---|---|
| Folded sheet | 1 sheet = 4 pages | Section count |
| 160-page block | 40 sheets = 8 signatures of 5 | Sewing time and swell |
| Sewing supports | 4 linen tapes, 30–40 mm apart | Spine strength |
| Thread | 18/3 linen, 0.6–0.7 mm, waxed 2–3 passes | Stitch tension and lock |
| Thread per block | 15–20 m | Knots and joins |
| Spine swell | +3–5% (3.5 → 3.6 mm per 10 sheets, 100 gsm) | Case fit |
| Boards | 2.0–3.2 mm greyboard | Cover stiffness |
| Case-in allowance | Cloth + 3 × board (≈7.7 mm at 2.4 mm) | Hinge and turn-in |
Fold, mark, pierce, then sew signature by signature, locking each kettle — about 10–20 minutes for 160 pages.
The kettle stitch is the lock that makes the seam a chain rather than a row: at each end the needle passes behind the stitch of the signature below before re-entering, so every section holds the previous one down. A kettle that is merely wrapped, not locked, is the failure called a loose kettle — the end signatures work free within a few openings.
Tension is the other failure point. Pull the thread snug, never strained: over-tightening puckers the spine and can tear the fold at the stations, while slack thread leaves the signatures sliding on the tapes. The named faults to inspect for as you go are puckering, loose kettles and torn stations.
Sewing adds measurable bulk. Ten sheets of 100 gsm paper measure about 3.5 mm closed and about 3.6 mm sewn — a swell of 3–5% across the block — so the spine you case is always wider than the pile you folded.
The measurements follow standard workshop practice for hand-sewn case bindings rather than any single manual or supplier.