Last night we saw the contestants of the Great British Sewing Bee inserting invisible zips into the Palazzo trousers. This is my favourite type of zip insertion because there is no visible stitching on the right side of the fabric and actually I think it is the easiest to do – if you have an invisible zip foot!
An invisible or concealed zip differs from a regular zip as the coils are on the underside of the zip and it is inserted before the seam is sewn. It is more easily sewn in ‘invisibly’ with a concealed zipper foot.
Steps for perfect invisible zips
- First neaten the seam allowances of the zip seam and then if working with lightweight fabric, fuse strips of interfacing in the seam allowance of the zip area (this helps give support and body to the zip).
- Press seam allowances to the wrong side to create a crease along the seam line.
- To ensure you fit the zip the right way up, pin the fabric pieces, right sides together and working on the wrong side of the fabric, lay the zip on the seam allowances with the coils uppermost centred over the seam line.
- Pin one side of the zip tape to the seam allowance only, then unpin the fabric pieces and remove the second section. Open the zip and continue pinning the zip tape to the seam allowance, baste in place down the centre of the tape if desired – remember you are only sewing it to the seam allowance and NOT the main fabric piece.
- Keeping the zip open and using a concealed zipper foot, place under the foot so that the coil of the zip feeds through one of the grooves on the underside of the foot and the needle will drop into the zipper tape.
- As you machine stitch the zipper in place, the coils continue to feed through the groove in the foot and the needle stitches as close to/virtually under the coils as they are pushed open by the foot. Stop when the machine foot touches the puller on the zip and lock off/fix the machine stitch. NB: You cannot sew to the very end with this type of zip.
- Close the zipper and check that the fabric virtually covers the teeth on the right (you shouldn’t be able to see the zip tape on that side at all). If you can – simply re-stitch, but move the needle one click over to be closer to the coil of the zip. Then put the fabric pieces together again to check to repeat for the other side of the zip.
- To complete the seam below the zip, close the zipper and pin the remainder of the seam together. Using a regular zip foot, stitch the seam, positioning the needle about 2mm to the left and above the zip stitching. Stitch to end of the seam (pull the end of the zip tape away from the seam at the start). Press seam allowance open.
- To finish, stitch the last bit of the zip tape to the seam allowance only so it doesn’t flap about. Finish by pressing carefully from the right side where you should only be able to see the zip pull peaking out the top. (Dress Image: Vogue pattern 9369 by Claire Shaeffer)