Sewing a jeans zipper the professional way is not difficult, but it requires a methodical approach. In this tutorial, I’ll show you all the steps to make proper jeans fly with shield, inspired by garment industry techniques and in particular how Lee jeans sew their zippers.
Tools for sewing a jeans zipper
- Metal jeans zipper
- Topstitching thread
- Zipper presser foot
- Jeans or topstitching needles
- Tracing pen (optional)
1. Mark the crotch seam
Using an awl or any other sharp object, punch a hole where the crotch seam should end. Punch just outside the seam allowance. This method is much quicker than a pen or tracing paper.
2. Sew the front crotch
Sew the front crotch seams together, ending where the little hole is (blue thread)
Baste the remaining crotch seam (white thread). This is where the clipping and the second hole comes in handy.
3. Trim away the right flap
Then trim away the right flap so that only around 1/2 inches/1.25 cm remains. Overcast the edge.
4. Topstitch the crotch seam (optional)
Clip the crotch seam just below the flap. The flaps should be open and the crotch folded to the left.
Stitch close to edge from the right side. The seam should be on the right side from the crotch
This is how the stitched seam looks on the inside. Notice who the seam is folded to the left and flaps are opened.
5. Attach the zipper on the trimmed flap
Place the zipper face down on the right (and trimmed) flap and stitch it to the flap, fairly close to the zipper teeth. Fold away the jeans front pieces so that you will only stitch on the flop.
6. Sew the zipper shield
Interface one side for added stability and overcast the edges,
Then sew the bottom seam of the shield.
Turn and press. There is no need to close the side seam if you want to create a shield the way it’s done by denim manufacturers.
7. Attach the fly shield
Slide in the shield underneath the trimmed flap and zipper.
Topstitch the on the left side of the zipper to attach the shield.
The finished shield, attached to the crotch seam.
8. Prepare for topstitching the zip fly
Option 1: Mark the seam on the fabric using a template.
Fold the fly shield to the right and pin it in place.
Topstitch the seam using (option B) a paper template. This a professional technique that is better than marking or tracing.
The first row of stitches is finished. You will secure the lower edge of the stitch from the other direction once the topstitching is done.
9. Topstitch the second row
Use an edge of the presser foot as your guide.
10. Remove the basting to open the crotch sam
10. Fold the fly shield to the left
This will prepare for the bar tacking seams that will keep the lower part of the shield in place
11. Stitch bar tacks
This will both secure the crotch seam and keep the fly shield from flipping back and forth. Now the jeans zipper is finished!