I have produced the first half decent exposed zip I’ve ever managed!
I can really recommend the exposed zip technique at http://aces.nmsu.edu/pubs/_c/C-221.pdf (it’s a PDF so you’ll need Acrobat Reader or Foxit or similar to view). This is for the kind of exposed zip where the zip is installed under the fashion fabric, like an ordinary centred zip, but you fold back the seam allowances of the seam you’re sewing it under to make a slot. The fashion fabric edges don’t meet over the zip and the zip tape shows. A picture probably makes more sense than a description so here’s my finished zip:
Here are a few extra notes on how I did it because I didn’t quite follow the tutorial.
I was using a separating zip so I zigzagged over the bottom end with a zero-length stitch to hold it together. The zip’s tape stopped at the bottom of the zip stopper, so I sewed a scrap of fashion fabric to the end to give me a longer ‘tape’ to sew onto the dress. This was a big help and I’ll definitely do it another time. I finished the edges of the scrap before sewing it on. It was cut to the same width as the closed zip and straight-stitched to the zip tape for about the last 1cm of tape.
I marked the ‘slot’ by laying the zip onto the fabric to determine the length of the slot. The tutorial has you just measure the length of the zip plus an inch, but anything involving measuring and zips doesn’t work for me. If I put the zip onto the fabric and mark exactly where I want the thing to go I find the end result’s more accurate.
I used strips of fusible interfacing to keep the edges of the slot stable. I applied it outside the stay stitching lines on the wrong side of the fabric. It really helps.
The clever bit in the method I used is that you sew the end of the zip to the little triangle of fabric at the end of the slot before sewing the sides of the zip into the slot. This seems to keep the end of the slot in good shape. My first attempt at sewing the end wasn’t very accurate, but I discovered it’s a bit like an invisible zip – you just keep sewing over it until it looks OK from the outside. The less said about the state of the inside, the better, though. And I am very glad I didn’t sew the side seams before doing the zip. This bit would have been really tricky if I hadn’t been able to lay everything out flat. Oh and I should have sewed the back seam a little bit further than I did. You can see the triangle is coming apart in the picture.
Here’s the end of the slot. I’m really pleased I got the white stripe in the fabric to line up with the plastic bit on the end of the zip tape. You can just see the scrap of fabric extending the zip tape below the stopper – the original zip tape stops where the plastic stops.
So I’m very nearly done. I haven’t actually tried it on yet, but as the side seams are still open I have a bit of wiggle room for fitting!