Bias-cut garments will follow your curves beautifully and are comfortable to wear. But what does bias-cut really mean? Wendy Gardiner, Brand Ambassador for The McCall Pattern Company, shares her top useful tips.

The ‘true bias’ is at 45° to the selvedges of the fabric and is stretchiest, which means you can create a softly flowing garment, with lots of stretch – which in turn often means you don’t need any fastenings. A pattern designed for bias-cut garments will still have the grainline on the tissue pieces to be lined up parallel with the selvedge edge of the fabric, but you will notice the pattern piece will be positioned diagonally – so seams are on the bias.

Finding the True Bias

If you are cutting your own bias-cut garment without a pattern, you need to find the true bias. To do this, fold the cut edge of the fabric up so it is parallel with one selvedge – the diagonal fold is on the true bias. Note: If you pull it along the diagonal fold, it will stretch much more than if you pull the fabric down the straight length or across the width.

Preparation

Cutting out – the fabric has a tendency to stretch easily, so pin the tissue to the fabric with plenty of pins to prevent it shifting and moving as you try to cut out.

Support fabric pieces – particularly long dress sections. Don’t let them droop and hang over the table edge, which can cause them to stretch out of shape before you even sew them!

Top Tips for Sewing on the Bias

Stay-stitch bias edges. Bias edges are often meant to stretch, but there will be some biascut seams that you don’t want to stretch – such as necklines. To keep these areas stable, add stay stitching before you begin construction. Stay stitching is simply a row of straight stitching just inside the seam allowance, about 12mm from the raw edge. For necklines, sew from shoulder to centre neck and then the other shoulder to centre neck rather than continuing to sew from shoulder to shoulder, which can result in stretching the fabric as you sew!
Stabilise stretchy areas – other seams that you don’t want to stretch include shoulder seams, and sometimes waist seams. Stabilise these seams by stitching seam binding or twill tape into the seams or use a stay tape (such as Vlieseline Edge Tape) that works well on lightweight fabric, knits and curved edges.
Use plenty of pins. Pin seam edges together with plenty of pins to help prevent them stretching as you work. Place pins along the seam rather than at right angles, to hold the fabric layers together more securely.
Use a walking foot to help feed the layers evenly.
When sewing bias seams such as side seams, hold the fabric in front and in back of the presser foot and stretch it gently as you stitch. this will allow the seam to ‘give’ as you stitch, and it will also relax into a smooth seam when you are finished. Steam iron it after stitching to leave a lovely ripple-free seam.

Stabilise shoulder seams with tape

Finishing seams

If possible use an overlocker with two thread or three thread to neaten the seam edge. Alternatively, use the over-edge foot and an over-edge stitch on your sewing machine which closely resembles an overlocker. The fabric edge butts up against the guide on the right of the foot and the stitch has a straight stitch to the left with a zigzag that goes over the fabric edge to the right.

French Seam

French seams also work well on lightweight bias-cut fabric. This seam adds a couture look to the inside of a garment. The finished seam, which should be very narrow, completely encloses the raw edges of the seam allowances.

With the WRONG sides together, stitch a 1cm seam. Trim the seam allowance to a scant 3mm and press them open.

Fold the fabric right sides together so the stitching is on right on the fold and press again. Stitch 6mm from the fold.

Press to embed the stitches and then press the neatened seam allowance to one side.

Double stitched seam

Alternatively sew a double seam – stitch the seam as usual, then stitch again with a small zigzag stitch close to the seam. Trim down the excess seam allowance close to the stitching.

Hemming

Hang the garment for at least 24 hours before hemming to let the bias seams droop if they are going to. Then level up the bottom edge before hemming by your preferred method.

Use a piece of tissue paper placed under the fabric at the start of the hemming to prevent the fabric being pulled into the feed dogs.

Rolled Hem

A rolled hem is ideal for lightweight and sheer fabric as the hem allowance is minimal and thus doesn’t look unsightly from the right side.

If possible use a rolled hem presser foot which has a metal coil at the front through which the fabric is fed and rolled as it is stitched.

To start off, turn under 3mm and again 3mm, finger press. Attach rolled hem foot but do not try and guide fabric into it yet. Stitch the first 2cm sewing close to the inner fold (move needle across if needed). Stop with the needle down, raise the presser foot and hook unfolded fabric into the coil on the foot.

Lower the presser foot and start stitching again, as you sew the fabric is fed into the coil of the foot and folds under itself. Note: It is easier to work if you hold the fabric slightly raised and to the left with your right hand, while guiding the fabric straight with the left.

Rolled hem without specialist foot:

Mark hem length then hem allowance of just 6mm. Fold up hem and very lightly press.

Stitch as close to fold as possible then trim away any excess hem allowance.

Fold the hem again along stitching, rolling stitches just inside the hem and stitch again close to inner fold.

Lettuce edging

This is another great hem on a bias-cut dress or skirt as you purposely stretch the fabric as you sew. If possible, use an overlocker, set to rolled hem (removing the left needle. Refer to user’s manual) and with a slightly tightened needle tension, stretch the fabric as you sew in front and behind the needle.

Or, you can do this by sewing machine – set your machine to a zigzag. Reduce the width to 3 – 3.5. Reduce the length to 0.4. (Note: You can also use an overedge foot. Check that the needle goes into the fabric easily and doesn’t hit the side of the foot or throat plate). Holding the fabric taut stitch on the hem edge, with right swing of needle falling off fabric, pulling fabric tight in front and behind the needle as you go.

Curved hem

Curved hem – a full-skirted dress will have a curved hem. To prevent ripples and unsightly folds, first level up the hem after it has been hanging for at least 24 hours.

Neaten the raw edge with an overlocker or over edge stitch. Ease-stitch the hem allowance by stitching 6mm from the edge with a long stitch length. Gently pull gathers slightly as you turn up a single folded hem. The gathers should be in the hem allowance only and not show from the right side. Top-stitch in place.

Armed with these top tips for sewing bias-cut fabric, enjoy making up one of the most comfortable garments you will wear.

MASTERCLASS: Sewing On The Bias