Whenever I teach bias binding and bias facing in class, the students get really confused. Here’s a pictorial demonstration of how to apply bias binding to curved edges. In this application, you will see topstitching on the bias.
STEP 1: PREPARE BIAS TAPE
For this demonstration, i’ve used a 2.5cm-wide bias tape. Press the tape into halves (wrong sides together), then into quarters, as shown above.
STEP 2: FIRST STITCH LINE
Align one of the edges of the bias tape to the curved edge (wrong side facing up) and stitch on the first creased line of the tape (see above).
This is what it looks like on the wrong side.
This is what it looks like on the right side.
STEP 3: FOLD BIAS OVER
Following the crease lines, fold the bias tape over the raw edges to the right side of the project, carefully tucking the raw edge of the bias under.
Above shows a closeup of what it looks like from the right side of the project. I like to make sure the bias tape covers the first stitch line.
STEP 4: SECOND & FINAL STITCH LINE
Top stitch the bias tape down, about 0.1-0.2cm (1/8″) away from the free edge.
This is what it looks like on the right side of the project. You can see a row of topstitching on the bias from the right side.
This is what it looks like on the wrong side of the project.
For other applications of bias, please see: