Sewing Techniques

Zips - centred and invisible zips

Zips are easily inserted if a proper zip foot is used, allowing the stitching to get as close to zip teeth as possible. Most machines have a zipper foot as one of the basic feet supplied. Unfortunately they do not all look alike, so do check your sewing machine users manual to identify your zipper foot.

To start our collection of zip insertion methods we look at centred zips – the most common method used and invisible zips, probably the easiest to insert.

General zip tips

• Always stitch each side of the zip in the same direction – ie: from bottom to top (or for invisible zip, from top to bottom).
• Always use a zip foot.
• If seam is to be basted before zip is attached, use long machine basting stitches and then clip through the stitches every 5 cm (2”) and at bottom of zip placement – this will make basting easier to remove later.
• If the zip is going to cross a seam (ie at waist of dress), reduce bulk in seam allowance of seam by clipping it 2.5 cm(1”) from opening, trim seam allowance to 1 cm (3/8”) and press open.
• Keep pull tab flicked up at all times – this makes it easier to raise or lower tab and slider as you stitch.

HANDY HINT: If correct length of zip is not available, buy a longer zip then mark from top to length required. Using thread double, hand stitch across the zip teeth a few times, approximately 13 mm (1/2”) below mark, to produce a new end stop for zip. Cut off below the stitching.

CENTRED ZIPS
Probably the most common zip insertion, also known as edge to edge insertion, this type has even rows of stitching showing on the right side, with the zip placed centrally and the teeth in line with seam line. Centred zips are used in the back or front seams of skirts, dresses, cushion covers etc.

To insert a centre zip use a REGULAR zip foot and thread to match the fabric as closely as possible.

HANDY HINT: If possible, take a wider seam allowance which makes it easier to handle and neaten the seam allowance of seam into which zip is to be placed prior to stitching any of the seam.

To insert centred zip
1. Mark zip placement on fabric, with mark at base of zip teeth.

2. Machine baste seam at zip position down to the mark, then change to regular stitch length to stitch remainder of seam down to hem. Press seam allowance open.

3. Working with wrong side of fabric uppermost, place closed zip face down over basted seam allowance, with teeth centred over seam line. Baste zip tape to seam allowance only.  

4. Turn work to right side and place on flat surface. Pin through all layers, pinning zip to garment.

HANDY HINT: If unsure about stitching a straight line, use a fade-away pencil or chalk pencil to draw a stitching line to follow an even distance from seam line on both sides.

5. Starting at the seam at bottom of the zip, stitch a few stitches, then with needle down, raise presser foot and turn work in line with marked stitching line or pin line. Lower presser foot and continue stitching towards top of zip. Stop before reaching zip pull, again with needle down, raise presser foot and gently push zip tab below presser foot so it is out of the way. Continue stitching to top, back stitching to secure firmly. Repeat for other side of zip.

HANDY HINT: It may be necessary to remove some of the basting stitches in order to push zipper tab below stitching and out of the way.

6. Remove all basting stitches and press carefully.

INVISIBLE ZIPS
The key to perfecting invisible zip insertion is to use an invisible zip foot – this really is essential. Once you have that, the invisible zip insertion method is probably the easiest of all zip insertions.

The invisible zip foot
An invisible or concealed zip foot has grooves underneath it, through which the teeth of the zip slide so that the needle stitches extremely close to the teeth if not under them! This closeness is essential for a perfectly stitched invisible zip.  The zip has the teeth on the underside of the zip, so that from the right side all that is seen is the zip pull. Plus the zip tape is sewn to the seam allowance only – hence no stitching on the right side of the garment.

HANDY HINT: Buy a zip at least 2.5 cm (1”) longer than required as you cannot stitch right to the bottom invisibly, so will effectively lose the last inch of the zip’s opening.

To insert invisible zip
1. Fold seam allowances to wrong side along seam line and press to form crease at fold. Do NOT stitch any of seam into which zip is being placed.

2. Open out seam allowance and with fabric RIGHT side up, place opened zip, face down on the seam allowance, with teeth along the crease. Pin in place.

3. With INVISIBLE zip foot stitch from top, with zip teeth in groove under the foot. As you stitch, gently uncurl zip teeth so that stitching is actually under the teeth which will curl back after being stitched. Go as far to bottom as possible. Back stitch a little to secure.

HANDY HINT: If preferred anchor zip tape in place first by stitching tape to seam allowance only, down middle of tape, using a REGULAR zip foot.

4. Repeat for other side of zip, stitching it to other seam allowance, again from top to bottom with teeth in line with crease of seam line.

5. Change foot back to REGULAR zip foot. Pin remainder of seam together and then start stitching from base of zip stitching to end of seam. Back stitch a little at start to strengthen stitching at base of zip.

This article has been written by Wendy Gardiner
Illustrations by Jane Bennett, tel: 023 92 412687