Adding a zipper fly to pants/overalls

If you make the Penny overalls for a boy, it will be essential for you to insert a zip in the front fly but you can also decide to add a zip fly because that’s what you will find on a vintage pair. It’s these little details that makes our hand made garments looking very professional. Either way, follow the tutorial above. This method of sewing a zipper fly will suit any sewing pattern for pants or overalls, it is not just about the Penny overalls.

First you need to draw a fly shield because this pattern piece is not included in the Penny overalls but it's pretty much a rectangle.

Draw a rectangle 9.5 cm wide, for the length of the rectangle, measure on the pattern piece (A) from the waist line to the circle mark and add 2 cm to this measurement. Cut into the fabric. Serge the long edges of the rectangle.

Fold the rectangle in half and cut the end diagonally.

Stitch the end 1 cm from the raw edge. 

Turn right side out and press.

Wrong side of the right leg facing you, draw the center front line (from the notch to the circle) then draw a line 15mm from the center front.

Cut the fabric following this second line.

Pin the front legs right side together and sew the crotch from the end to the circle marking, backtack.

Then baste from the circle marking to the waistline.

Clip the fabric near at the circle marking.

Serge the crotch seams together.

Press the fly seam allowances open and then press the crotch seam allowance to the left front.

Right side facing you, topstitch the left rise 2mm from the center seam.

To sew the zipper, flip the fronts over to the side because you just want to sew on the right extension.

Put your zipper face down on the right front extension. Line up the zipper tape to the bottom of the extension. Sew close to the zipper teeth.

Install the fly shield on the right front under the zip.

Flip the fronts to the side ans stitch the left side of the zipper to the fly shield.

Open up the fronts, flip the zipper to the left, wrong side of the zipper facing you and pin the zipper to the left fly extension (only pin the zipper to the extension not the left leg).

Flip the fronts to the side. Sew the zipper to the left extension. Voilà, c'est terminé !

Now be a good time to do any topstitching and bartacking. You can follow the instruction booklet to do so. If you are unsure of your zipper fly you can unpick the basting stitches and double check to see if everything is looking good before doing all the topstitching and bartacking ;-)