How to sew bias tape accurately?

Bias binding is a key element in sewing, used to add a clean and aesthetic finish to the edges of a fabric. Whether for a garment or an accessory, it protects the fabric while adding an elegant touch.

In this article, we will detail the steps involved in making bias binding, the different methods of applying it, and the techniques for achieving a perfect finish .

How to make bias?

If you want a bias binding that perfectly matches your fabric, it's best to make it yourself . This allows you to adapt its color, width and flexibility to suit your project.

Cut the bias strips

To obtain a flexible and easy-to-apply bias, cut the strips at a 45° angle to the edge of the fabric.

• Place a set square on the edge of the fabric and draw a first diagonal line.
• Draw a series of stripes parallel to the first drawn line of the desired width (usually 4 cm).
• Continue cutting several strips until you get the length you need.

Bias cutting allows the fabric to better fit rounded shapes , because the bias is the part of the fabric that stretches the most. It is therefore easier to "shape".

Forming the bias with a bias maker

Once the strips are cut, they must be folded in half to obtain a bias tape ready to be applied.

• Pass the strip of fabric through a bias tape maker (or mouse).
• Slide slowly while ironing immediately to set the creases.

If you don't have a bias tape maker, you can manually press the folds with an iron.

Join bias strips to lengthen it.

If one strip is not enough for your project, you will need to assemble several pieces of bias tape .

• Place the strips right side to right side , forming a right angle (leave the corners sticking out).
• Draw a diagonal from the top left corner to the bottom right corner and machine stitch.
• Open the seam , iron and cut off the excess fabric, leaving a 5 mm margin (to avoid thickness).

How to put a saddle bias?

It involves wrapping the edge of the fabric with the bias to obtain a clean finish.

Attach the bias to the wrong side of the fabric

• Open the bias and place it right side against the wrong side of the fabric , leaving 1 mm overhang .
• Stitch in the fold of the bias tape following the edge of the fabric.

This first seam helps hold the bias in place before folding it over.

Fold down and fix the bias on the right side

• Fold the bias tape over to the right side , completely covering the edge of the fabric and the previous stitching. If you have trouble hiding the previous stitching, trim the seam allowances.
• Pin carefully and stitch 1 mm from the edge to secure permanently.

To avoid creases and ensure a good fit, it is advisable to flatten the seam with your fingernail before stitching.

How to get a clean finish on the edge of a bias tape?

Classic method: straight and reverse seam

For a clean finish:

• Fold the bias tape in half lengthwise and mark a line where it protrudes from the fabric.
• Sew across the width of the bias , starting from the fold made to the first fold of the bias.
• Cut off the excess and turn it over with a sharp tool to form the angle.

This technique is ideal for clean, structured angles .

Hollow out an angle to avoid thickness

If the fabric is thick, it may be necessary to hollow out the corner to reduce the thickness:

• Remove a portion of the fabric in the center of the corner , without touching the seams.
• Tuck the ends inside , then iron to secure the fold.

This technique is particularly useful for bias binding on thick fabrics such as denim or wool.

How to apply bias to a curve?

On rounded edges, the bias binding is more flexible .

• Pin the bias tape along the curve , making sure it fits the shape of the fabric.
• Sew slowly , maintaining light tension to avoid creases.
• Turn over and iron carefully to secure the bias tape.

If the curve is very tight, it may be helpful to make small cuts (notches) in the seam allowance to allow the bias tape to fit better.

How to sew a bias tape flat?

Flat bias binding is a finish where only the reverse side is visible .

• Place the bias right sides together with the fabric and stitch in the fold.
• Turn the bias tape inward so that it is only visible on the wrong side.
• Stitch 1 or 2 mm from the edge to fix permanently.

This technique is ideal for hems and lining finishes .

Conclusion

Whether it's to reinforce a seam, structure a garment or add an aesthetic touch, bias binding is an essential technique in sewing .

To remember:

• Cut the bias at 45° for more flexibility.
• Join several strips together with a diagonal seam.
• Place a bias tape on a saddle or flat depending on the desired effect.
• Adapt the seam to the curves for a smooth finish.
• Iron after sewing for a clean and lasting result.

A well-placed bias adds real value to creations and guarantees a neat and professional finish .