An Illustrated Guide to Butterfly Stitch

By Maia Balint, Graduate Diploma Conservation Studies, specialising in Books and Library Materials

Learning bookbinding techniques is an important aspect of training as a book conservator. Knowing how different structures and decorative techniques were achieved helps a conservator to understand the object they are looking at and to make decisions about how best to conserve it. Sewing techniques are one of my favourite things to learn, so I was very excited when a visiting instructor, John Mumford, introduced us to Butterfly Stitch.

Butterfly Stitch is a modification of all-along sewing - one of the most basic patterns for sewing multi-sectional textblocks - in which the stitches are gathered together every three to four sections. This results in little bundles of stitches, resembling butterflies, along the spine. Textblock sewing can be supported or unsupported. In supported sewing, the thread is secured to another material (such as lengths of cord or tapes) that connects the sections; in unsupported sewing, only the thread connects the sections. Butterfly Stitch is typically supported on flat, textile tapes and each tape corresponds to a sewing position.

Finally, a note on changeover positions: there are a variety of different techniques for moving from one section to the next. In a sense, changeover techniques are independent from sewing styles as they can be used interchangeably with many different sewing patterns. For Butterfly Stitch, John taught us to use a full-loop changeover stitch. In this guide, I have included close-up diagrams for few different changeover techniques, including John’s full-loop changeover stitch. However, for the sake of clarity, I have used the simplest changeover technique - the span stitch - in larger illustrations.

Let’s go!

Step 1: Making the holes - the hole positions for Butterfly Stitch are the same as those for all-along sewing.

Step 2: Sew first two or three sections all along: start from outside of the section and weave the thread through the holes and around the tapes. Don’t forget to leave a tail of thread at the beginning for tying-off later.

Span Stitch (Unlinked) - Go directly from one section into the next. There will be alternating gaps in the sewing resulting in a lot of movement.

Kettle Stitch (Knotted Link) - Loop the thread around the previous stitch (below the previous section) and pull the needle through the centre of the loop before entering the next section. This results in a knot, which restricts movement.

Half Loop Changeover Stitch (Linked) - Loop the thread through the previous stitch (below the previous section) before entering the next section. This forms a chain of half loops on the spine.

Full Loop Changeover Stitch (Linked) - Loop the thread through the stitch two sections below the current section before entering the next section. This forms a chain of full loops on the spine. John recommends this technique.

Step 3: When sewing the third or fourth section, at each sewing position, link loop the thread around the stitches on the previous two to three sections. The thread exits the section on one side of the tape, comes down over top of the previous stitches, back up underneath the previous stitches, loops around itself and is pulled tight, then re-enters the section on the other side of the tape.

Note: You need to tension the sewing as you go because this linkage locks the thread and you may need to manoeuvre the knot in order to centre it.

Step 4: Repeat this pattern - sewing two or three sections all-along followed by one section linking the previous ones - until the textblock is complete. Tie off the threads with each end with a double kettle stitch and admire your butterflies!