Zips - Invisible zips
These special zips only come in three lengths: 22 cm (9 inches), 40 cm (16 inches) and 60 cm (24 inches). The zip should be at least 2 cm (1/4 inch) longer than the zip opening. It is stitched in before joining the seam below the zip. A special presser foot is required to sew in this type of zip.
Sewing in an invisible zip:
Open the zip and push the coil back with your thumbnail to reveal the seam between the band and the coil. Place the open zip face down on the right side of one opening edge. So that the zip can be stitched in place exactly along the marked seam line, calculate the distance between the zip tape and the fabric edge as follows: seam allowance width minus 1 cm (3/8 inch) = distance from the fabric edge. Pin the top end of the zip tape in place at the calculated distance from the edge of the fabric. The bottom end of the zip will overhang the marked end of the. Place the presser foot on the zip so that the coil is in the notch to the right of the needle. Stitch the zip in place from the top to the marked end of the opening. Close the zip. Place the other zip tape face down on the other opening edge and pin in place at the top. Open the zip again. Place the presser foot on the top end of the zip so that the coil is in the notch to the left of the needle. Stitch the zip in place from the top end down to the end of the opening. Close the zip. Now stitch the seam below the zip, from bottom to top. Turn back the loose lower end of the zip to the seam allowances, ending as close as possible to the last stitch of the zip seams. Cut off surplus zip and bind the end with a scrap of fabric.