Please watch the YouTube video made by "iheartstitching" - I followed her instructions to make this tutorial but I cut out the top stitching and use of interfacing.
To determine how big you want each piece, make the width the same as your entire zipper piece and the height however deep you want your bag to be (plus an inch or so).
I eyeballed my measurements but made all 4 pieces exactly the same size - as long as you do the same you'll be fine.
You'll want to place one piece of the exterior fabric (face up) followed by the zipper. Although I placed the zipper facing up in the picture you will actually want to place it upside down!!!
On top of the zipper place one piece of your liner fabric (face down). Line up all the edges.
I designed my bag to have different sides so be careful to follow written directions over image to ensure accuracy.
Pin the edges.
You can open the sandwich up after you pin the pieces to double check that everything is the way you want it.
You'll want to change out the presser foot on your sewing machine. Use the zipper foot instead as it will allow for the extra width of the metal zipper.
Attached zipper foot, ready to go!
Open the zipper a bit (while it's still pinned) so that you can start the seam.
Don't forget to backstitch when starting and ending seam to lock stitch.
Once you've sewn up to the zipper head open the fabric up and pull the zipper pull back up. This will keep your edges lined up and easier to sew.
When done you can check to see if everything looks good. I didn't sew my fabric very close to the metal because I wanted it to show on outside. There are plenty of tutorials online about other ways.
The whole thing should look like this at this point...
Next lay your other exterior fabric piece (face up) and the lay the untouched edge of the zipper down on top of it. The exterior fabric that's sewn to the zipper should be face down.
You can double check the accuracy once it's pinned.
Next lay your second liner fabric piece down (face down).
You've now created another fabric sandwich that should look pretty familiar now.
When done you can open things up and check it out. Remember that I want a double-sided bag so I can create a print on one side.
Iron and trim up edges. This is when I measured a bit, especially the length from the sewn edge of fabric where it meets zipper to the bottom edge of fabric. This part should be equal on each side.
You can open up your layers now... Both liner fabrics on one side and both exterior fabrics on the other... (Remember that I'm alternating pieces, normally the sides would match).
Unzip your zipper about 2/3 of the way down.
Make sure that the raw inside edges of your zippers are together on the same side (facing inward away from top of zipper) before pinning together.
You can check which side the top of the zipper is on by opening it up a little.
Pin all the edges and start sewing about 1/4-1/2 seam all the way around starting on the liner side. You have to leave an opening on the bottom of your liner fabric. Now you'll want to test this.
You will reach into the hole at the bottom of the liner all the way through (over the open zipper) to the bottom edge of the bottom of the outside of the bag. You'll be able to check that it's all ok.
When you know it's cool you can push everything wrong-side-out again so you can trim the corners and excess fabric from edges.
Then pull everything back the right way again and push out all the corners.
You'll now have the hole in the lining to deal with. Press everything with iron including the folded under edges in the hole. Pin this and run it through machine.
You'll notice my bobbin thread is light and my top thread is dark / this is intentional.
Then tuck the liner in and push out corners again.
And there you have it. Iron the sucker and marvel at your mad skills.
Sweet. You rock!
And this is my bag after the print is completed. You can learn how to make a similar print using fabric paint and freezer paper in my next tutorial! (Shameless plug...)