Step by step

Hemming jersey: twin needle, coverstitch and zigzag

Why a straight stitch snaps on a jersey hem, how to sew a shop-bought-looking hem with a twin needle, what stops tunnelling and which alternatives there are.

On the left a hem from the right side with two parallel lines of stitching and a strip of tape as a guide, an arrow shows the sewing direction. On the right the same spot from the inside: the folded hem with the bobbin-thread zigzag

The hem decides whether a jersey garment looks homemade or shop-bought. It has to stretch, lie flat and not ripple.

Merl, the sleeves of Pulo, Han and Wleg all include a 2 cm hem. Here we show you the twin needle, which works well on any ordinary sewing machine, and what to do if it still ripples. The most common problems with jersey in general are in 5 jersey traps.

What you need

Stretch twin needle, needle spacing 2.5 to 4 mm
Two spools of thread in the same colour and a bobbin
Iron
Sewing clips instead of pins
Optional: narrow fusible hem tape for thin jersey
A scrap of the fabric for testing

Step 1

Why the hem has to stretch

On the left a stretched jersey hem with a snapped straight stitch (wrong). On the right a stretched hem with two parallel twin-needle lines that hold (right)

Jersey stretches, a straight stitch doesn't. Pull a top over your head or sit down in leggings and the thread snaps. So a jersey hem needs a stitch that moves with it:

Twin needle: two parallel lines of stitching on the outside, a zigzag from the bobbin thread inside. Looks shop-bought.
Coverstitch: the same look, even stretchier, but needs its own machine.
Narrow zigzag: always works, but looks homemade.

Step 2

Preparing the hem

On the left a piece of jersey with the hem pressed under and an iron, the hem width marked. On the right a pressed hem with hem tape inside, held with three clips

Press: press the hem allowance to the inside, 2 cm on our patterns. Lift and lower the iron rather than sliding it, or the jersey will distort.
For thin jersey: lay a narrow fusible hem tape into the fold and press it in place. That prevents rippling.
Clips instead of pins: pins distort the edge and get in the way when sewing from the right side.

Step 3

Threading the twin needle

Two spools whose threads run separately to a twin needle with two points; the needle spacing is marked. Next to it a bobbin

Needle: a stretch twin needle with 2.5 to 4 mm spacing. Ordinary twin needles skip stitches on jersey.
Top threads: two spools, thread both together but separate them at the tension discs if your machine allows. Just before the needle, each thread goes into its own eye.
Bobbin: as normal.
Stitch: straight stitch, length 3 to 3.5 mm. Never zigzag with a twin needle, or it will hit the needle plate and break.

Step 4

Sewing from the right side

A twin needle always sews from the right side. The zigzag forms on the inside and has to catch the folded edge.

Mark a chalk line on the inside just below the hem edge, or stick a strip of masking tape on the needle plate as a guide. You can't see the edge from the right side.
Sew at a steady pace without pulling or pushing the fabric. Let the machine feed it.
On tubular hems (sleeves, legs) don't push over the seam; turn slowly. At the end, pull the threads to the inside and knot them.

Step 5

Avoiding tunnelling

On the left a cross-section of a hem where the fabric bulges into a ridge between two lines of stitching (wrong). On the right a flat hem and a tension dial being turned lower (right)

If the fabric between the two lines of stitching bulges into a little ridge, that's tunnelling. The bobbin thread pulls the two lines together. What helps:

Loosen the top tension a little, e.g. from 4 to 3, and test on a scrap.
Use longer stitches, 3.5 instead of 2.5 mm.
Add hem tape to stabilise the fabric.
Choose narrower spacing, 2.5 instead of 4 mm.

A slight ridge often presses flat with steam.

Step 6

The alternatives

Three jersey strips one below the other: at the top coverstitch with two lines and loops between them, in the middle a narrow zigzag, at the bottom a triple zigzag

Coverstitch: if you sew a lot of jersey, the neatest and stretchiest solution. Two or three lines on top, a chain stitch underneath.
Narrow zigzag: width 1 to 1.5 mm, length 2.5 mm. Works on any machine and holds well. Ideal for test garments.
Triple zigzag (stretch zigzag): very stretchy, good for leggings hems that have to go over the heel.

And sometimes the best solution is no hem at all: a cuff or a pretty edge like the lace on Pulo saves you hemming altogether.