How to Join New Thread Midway Through Sewing a Text Block Without the Knot Slipping

Stop while the remaining thread is still comfortable to manipulate. Book-repair.com recommends adding a length when approximately 6 inches remain on the needle. Treat that as a useful planning point rather than a reason to squeeze in another stitch: you need enough thread to form the join, position it, and test it. Its instructions place the knot inside the signature, between sewing holes and close to the last sewing station. Tying knots

Before removing the needle, note where it would go next. Open the section at its center fold and identify the thread emerging from the last hole. Set out a fresh length of your existing sewing thread, the needle, and scissors. Using the same thread keeps this first attempt straightforward; changing materials introduces another variable when you are trying to understand a slipping join.

If the remaining end is too short to hold through the knotting steps, a practical recovery is to undo the most recent stitch or stitches until you regain a manageable end. Record their route before undoing them. This is a workflow recommendation: recover enough thread to make a controlled join, then restore those stitches in order.

For the method here, put the join inside the center fold, immediately beside the last hole but clear of its opening. The knot should remain on that side of the paper when sewing resumes. Book-repair.com explains that a join does not readily pass through a sewing hole, so its recommended position is between the stations. Tying knots

Deal with loose sewing before locking the new thread in position. In his original long-stitch instructions, Douglas W. Jones advises taking up slack before adding thread and locating the knot so later tension adjustments will not require pulling it through a hole. Although his tutorial describes a particular binding structure, that placement check is useful here too. Sewing the Sections to the Cover

Trace the next stitch with your finger before tying. Ask: when I pull the new thread through the next hole, will this knot stay where it is? If the planned route would drag it through the paper, reposition the join first. This simple rehearsal separates a placement problem from a knotting problem.

For clarity, the old thread is the end attached to your sewing. The new working length is the long portion you will continue sewing with. Each also has a short end, or tail. Leave those tails available until the join passes its test.

1. Make a loop near the end of the new thread.
2. Bring a bight—a folded portion of thread—from behind and through that loop. Tighten the first loop around it to form an adjustable slip loop.
3. Feed the old thread’s free end through the adjustable loop.
4. Position the join beside the last sewing hole.
5. Pull the two ends of the new thread apart to close the loop around the old thread. Continue until the knot seats and you feel the locking click described in Brighton’s instructions. The Weaver’s Knot

Work slowly enough to distinguish positioning from tightening. First bring the loose join to its intended location; then seat it there. Keep track of the new working length throughout, so you can test the part that will actually carry the sewing tension.

Gently pull the new working thread while observing the join. Brighton’s instructions explicitly require this test and say to retie the knot if it slips off the old thread. Feeling a click is part of forming the knot; checking whether it holds is a separate step. The Weaver’s Knot

Use this practical inspection sequence before reaching for the scissors:

• Watch the old tail: does it withdraw into the knot when you pull?
• Watch the join: does it remain compact, or does a loop reopen?
• Watch the sewing: is apparent movement actually slack arriving from the preceding stitch?
• Check the route: will the next stitch leave the join inside the fold?

These observations help identify what needs correcting. A tail withdrawing suggests the connection is moving. A stationary knot accompanied by a shrinking loose stitch points to tension elsewhere. Do not trim while you are still deciding which movement you are seeing.

Treat the following table as a diagnostic sequence derived from the knotting, placement, and tension instructions above. Change one thing at a time, then repeat the gentle pull test.

What you observe	What to check	Next action
The new thread comes away from the old end	Whether the adjustable loop locked during tightening	Open or remake the join and repeat the full sequence
The old tail steadily disappears	Whether the join holds under working-thread tension	Retie before shortening either tail
The knot holds, but the preceding stitch becomes loose	Slack in the existing sewing	Redistribute that slack before continuing
The knot moves toward a sewing hole	Join placement and the next stitch’s route	Reposition it so it stays between holes
You cannot manipulate the remaining end	Available old-thread length	Undo enough recent sewing to recover a usable end

If the same attempt fails repeatedly, practice the sequence with two spare pieces of the actual sewing thread. That removes the text block from the handling problem and lets you watch the knot form. Once the practice join holds under a gentle pull, repeat it in the book. This is a suggested troubleshooting exercise, not evidence that every thread behaves identically.

A square knot is a documented alternative: Jones specifically uses one when adding thread in his long-stitch binding. To form it, cross the right end over the left and pass it through; then cross the now-left end over the right and pass it through. Book-repair.com gives the same alternating sequence for its square knot. Seat and test the join before trimming. Sewing the Sections to the Cover, Tying knots

There are also joins intended for a different stopping point. The Guild of Book Workers’ published Ascona-knot instructions specify joining at the end of a section, using the preceding sections and kettle-stitch area. That makes it an option to study when you can plan a section-end change; it does not provide the same mid-section procedure described here. Tips & Techniques

Once the connection holds, trim only the surplus tails, keeping your scissors away from the new working length. The cited instructions do not establish one universal tail measurement for every thread, so avoid treating an arbitrary close cut as part of the knot’s success. Rethread the needle if needed and follow the next stitch you identified before stopping.

As you continue, avoid piercing existing thread when reusing a hole. Jones explains that sewing through the thread makes subsequent tightening difficult. After the next stitch, inspect the join again while it remains accessible and check that the surrounding sewing is evenly snug. Sewing the Sections to the Cover

A successful thread change leaves you ready to continue the same sewing pattern, with a compact join that stays in its intended place under a gentle pull. Establish that result before trimming and moving on; it is much easier to correct the connection while both ends remain accessible.

• University of Brighton, Visual Communication Technical Resource: The Weaver’s Knot.
• Book-repair.com: Tying knots.
• Douglas W. Jones: 6. Sewing the Sections to the Cover.
• Guild of Book Workers Newsletter, Number 112: Tips & Techniques.