True Bias Tape
A full bias tape is an anti-stretch tape cut at approximately 45 degrees to the fabric grain, giving it stretch that conforms to curves.
Contents5 sections
Definition and Overview
A full bias tape is a tape cut diagonally to the warp and weft of woven fabric, generally at about 45 degrees. Although it is woven fabric, it stretches easily on the bias and conforms well to curves.
When used as an anti-stretch tape, it uses the stretch of the bias direction to shape curved areas while preventing seam allowances and edges from stretching more than necessary. Depending on the tape material, weave, and whether or not it has adhesive, its stretch and holding power will vary.
Areas of Use and Function
It is mainly used on curved seam allowances and facing sides, such as necklines, armholes, arm openings, and front edges. It follows curves smoothly while preventing stretching and distortion during sewing, helping stabilize the finished seam.
It is especially effective as partial reinforcement for cut edges that tend to stretch on the bias, or for thin fabrics and fabrics that are difficult to control. However, because it is designed to use the tape's stretch, it may not be suitable for areas where you want to firmly fix a straight section.
- Stabilizing curves such as necklines and armholes
- Controlling stretching and waviness at front edges and facings
- Maintaining seam allowance shape during curved sewing
Types and Differences in Cutting
Types without adhesive are used by sewing them on. They are less affected by pressing conditions and can be fixed by sewing while checking compatibility with the material, but care is needed to avoid shifting during sewing or overstretching.
Adhesive types are used by temporarily fixing them with an iron or press, or by bonding them in place. While they make it easier to stabilize position before sewing, if the bonding temperature, pressure, or time is not matched to the outer fabric, they can cause peeling or fading.
Straight tape is cut parallel to the grain and stretches very little, so it is suitable for anti-stretch use on straight sections. A half bias tape is cut at a smaller angle than full bias, and is used for applications that require less stretch than full bias while still accommodating some curves.
Selection and Sewing Precautions
Choose the width according to the seam allowance width, the area to be reinforced, and the sewing position. If it is too narrow, it will not support the required area well; if it is too wide, it may become excess on curves, so trial samples matched to the sewing specification are important.
Select the stretch according to the properties of the outer fabric and the area. When following curves is the priority, a stretchy tape is suitable; when shape retention is the priority, a less stretchy tape is better. Pulling the tape while attaching it can cause shrinkage or puckering, so let it settle naturally.
For adhesive types, check the adhesion to the outer fabric, appearance, and condition after washing before mass production. With heat-sensitive fabrics or napped fabrics, attention is also needed for changes caused by temperature and pressure, as well as any adhesive seepage.
Frequently Asked Questions
Are full bias tape and regular bias tape the same?
Regular bias tape is a broad term that also includes use for binding fabric edges and for decoration. Full bias tape refers to material cut at about 45 degrees to the grain. For anti-stretch applications, also check whether it is folded and whether it has adhesive.
What kinds of areas are full bias tape suitable for?
It is suitable for areas such as necklines and armholes where you want to control stretch while following curves. On the other hand, for areas such as shoulder seams where you want to firmly fix a straight line, a less stretchy straight tape may be more suitable.
Does adhesive full bias tape not need to be sewn?
Whether adhesive alone is sufficient depends on the outer fabric, the area of use, and the load during washing and wearing. Since many specifications also sew after bonding, check the required holding power and process, and confirm peeling and appearance effects through trial samples.
