Basics

Binding edges with bias tape: edges, curves, corners

Bias tape gives you neatly bound edges without a hem. How to do it on straight edges, curves and corners, and how to join the start and end.

Three steps: the seam stops just before the corner, the tape is folded up at 45°, then down along the next edge, and the seam continues

When binding, you wrap bias tape around the raw edge. The cut edge disappears inside it, and you need neither a hem nor a finish. That's handy on necklines and armholes and anywhere several layers come together.

On our wallet Kirsche, for example, all outer edges are bound. With a little practice it looks really neat.

You can buy the tape or make it yourself, even from scraps: Make your own bias binding.

What you need

Double-fold bias tape, bought or homemade
Pins or fabric clips
Thread to match the tape
A new sewing machine needle
Iron
Sharp scissors

Step 1

Prepare the edge

Two fabric layers basted together close to the edge, scissors trimming the seam allowance straight, next to it a piece of tape of the same width

The tape only covers as much as it is wide. If the seam allowance is wider, it peeks out or the tape bulges.

Trim the seam allowance to the width of the finished tape, unless the instructions say otherwise. For 1 cm tape, that's 1 cm.
The edge must be even. Trim frayed or wavy spots straight.
Baste several layers, such as fabric with interfacing and lining, together close to the edge first. Then nothing shifts while binding. Which interfacing suits what is explained in Fusible interfacing: which one for what?.

Wrap the tape around the edge once as a test. That shows you whether everything disappears inside.

Step 2

Method 1: sew in the fold, wrap, stitch down

The opened tape lies with its raw edge along the fabric edge, the seam runs in the first fold line. A cross-section above shows with an arrow how the tape wraps around the edge

This method takes a little longer, but it's the most accurate.

Open the tape and place it right sides together along the edge, raw edge to raw edge.
Sew exactly in the first fold line.
Wrap the tape around the edge to the other side. There, the folded edge sits one or two millimetres past the seam.
Pin it and sew from the right side in the ditch, exactly in the seam. That catches the back as well.

If you prefer a visible topstitch: sew the tape to the back first, wrap it to the front and edgestitch the folded edge from the right side.

Step 3

Method 2: wrap in one go and edgestitch

Folded tape encloses the fabric edge and is held with clips, the presser foot edgestitches. The cross-section shows the seam catching both sides of the tape

It's faster if you slide the folded tape straight over the edge and stitch both sides down in one pass.

Push the edge all the way into the fold of the tape. If your tape has a slightly wider half, that one goes underneath.
Pin or clip it every few centimetres.
Edgestitch from the top along the folded edge and check now and then that the underside is caught.

It's quick, but less accurate: if the underside slips away, you get a gap. For a start and for thick layers, method 1 is safer.

Step 4

Curves: ease slightly on the outside, stretch slightly on the inside

Left: a piece with an outward curve, arrows push the tape together (ease). Right: an inward curve, arrows pull the tape apart (stretch)

Curves show why the tape is cut on the bias. Still, it needs a little help.

Outward curve, where the edge bulges outwards, such as rounded corners: ease the tape slightly, feeding it loosely without pulling. Otherwise it draws the edge in and the piece cups.
Inward curve, where the edge goes inwards, such as a neckline or armhole: stretch the tape slightly. Otherwise it wrinkles once it's wrapped.

It's easiest if you press the tape into shape first: lay it on the ironing board in the right curve and steam it until it holds the curve on its own.

Step 5

Outer corners with a mitre

At an outer corner you fold the tape into a mitre, a diagonal fold. That keeps the corner sharp and flat.

Sew towards the corner and stop as far before it as your seam is from the edge. For 1 cm, that's 1 cm before the corner. Backstitch and cut the threads.
Fold the tape up at a 45° angle so it lines up with the next edge.
Then fold it down along the next edge. The new fold sits exactly on the top edge.
Continue sewing from the edge.

When you wrap the tape, the corner on the other side also folds diagonally. Lay it neatly and pin it.

Step 6

Start, end and finishing

Left: the end of the tape overlaps the start folded back by 1 cm. Right: a round opening with continuous tape and a diagonal joining seam

Don't start at a corner, but at an inconspicuous, straight spot.

Simple: fold the start of the tape 1 cm to the wrong side and start sewing from there. At the end, let the tape run about 1 cm past the folded start. That way only the clean fold shows on the outside.
Completely smooth: for a closed ring, sew the two ends together on the diagonal, just like when joining strips, then sew on the last bit.

Finally, press everything. Set the iron down instead of sliding it. The topstitching sits close to the edge, the tape is the same width everywhere and has no puckers.