How to thread elastic
An elastic waist is the easiest waistband there is: fold the top edge into a channel, thread elastic through, join the ends. The three things that go wrong are losing the end inside, cutting it the wrong length and twisting. All three are avoidable.
1. Make the casing
The channel the elastic runs in. Make it at least 5 mm wider than the elastic — cut to the exact width, the elastic will not feed through.
- Fold the top edge over by 1 cm, then again by the width of the casing, and press.
- Stitch close to the lower fold, leaving a 3 cm gap for threading.
- Backstitch at both sides of the gap. This is where the strain lands when you pull the elastic through.
2. Thread the elastic
A bodkin is the tool for it, but a large safety pin does the same job.
- Pin the bodkin (or safety pin) to one end of the elastic.
- Pin the other end to the outside of the fabric before you start. Skip this and the free end disappears into the channel — the single most common way this goes wrong.
- Work the bodkin round the channel, gathering the fabric along and pushing it back as you go.
- Bring both ends out, overlap them by 2 cm and stitch a box with a cross through it.
- Feed the join back inside and close the gap in the casing.
3. How long to cut it
Measure the body, not the garment. As a starting point:
- Waist: your actual waist measurement minus 2–4 cm, plus 2 cm to overlap.
- Cuffs and hems: about 85% of the actual opening.
- Children: elastic that is too tight leaves marks. Take less off than you would for an adult.
- Pin the ends before you sew them and try the garment on. Until they are stitched you can change your mind as often as you like.
4. Twisting and other trouble
- It twists inside the channel: stitch through the casing and the elastic at the side seams, once on each side. It cannot roll after that.
- The channel is too tight: make it 5 mm wider than the elastic. Wide elastic in a narrow channel folds over on itself.
- It has gone slack after washing: elastic tires. Leave the gap in the casing closed with a few hand stitches and you can replace it later without unpicking a seam.
Frequently asked questions
- The end disappeared into the casing.
- Pin the free end to the outside of the fabric before you start threading. If it has already gone, pull it back out with a crochet hook or feed a safety pin in from the other side.
- How wide should the elastic be?
- 2.5 cm for an adult waist and 1.5–2 cm for children is a good default. Wider elastic is more comfortable but needs a wider channel.
- Can I use elastic on a knit?
- Yes, and it works well. Just do not stretch the fabric as you stitch the casing, or the seam will ripple.
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