Including Zipper in Pattern

[BoonesDaddy]

Ha all. So every time I make a pattern and sew in the sipper, the panel I am working on shrinks. I finally realized that I was not including the doubling of the seam allowance when I top stitch. However, how do I include the width of the zipper in my pattern...Do I just add 1/2" for the zipper exposure and tack that on to the matching panel? Is there a better way of doing all this?

Thanks for your help! There's a lot more to sewing than I realized...

Edit: I should add that this is really only giving me trouble if one side is a diagonal...Pretty straightforward on a square, but adding in the different allowances on the diagonal is hard to get my head around.

[glenndandy]

Coincidentally chatted with a buddy today that has made many...sew the zipper by the yard across the back of the pattern...it should be too long, you'll stitch across it later without issue. Then cut the fabric from the front side of the pattern, along the centerline of the zipper,fold each side under  and run it through again....(I think) Uuuh, Joey?

[DesertDog]

What I do is different than what most folks do, but you could start with the way I do my zippers.  Then, just add on a storm flap to keep out the elements.  

All I do is use my utility knife to cut an opening like this:

\                                   /
 -------------------------
/                                  \


From the pictures, and all three bags were made by just making an opening in a single piece of fabric, the inside stitching is to fold and hold the initial opening.  The outside stitching is to attach the zipper to the outer and inner layers of the opening.

I should have used a bar tack (and will on future projects) on the ends of the zipper openings.  But even though there is a little fraying on the corners of my zipper openings, I know it will be years until there is any real issue with it.

But, most folks should and would bar tack those ends to prevent future issues.

Just my way of doing it.  Have a dual-compartment frame bag I'll be making for my hardtail that I'll do the same way.  

[Eric]

bones - the allowance varies depending on how you are sewing in the zipper and the width of the foot on your machine. So to test: Take a piece of fabric, say 5" wide. Cut it in half, install the zipper then measure the width again. The difference will give you the proper allowance with whatever method you're using for the zip. FYI - it might also not be anything...

[Smo]

Coincidentally chatted with a buddy today that has made many...sew the zipper by the yard across the back of the pattern...it should be too long, you'll stitch across it later without issue. Then cut the fabric from the front side of the pattern, along the centerline of the zipper,fold each side under  and run it through again....(I think) Uuuh, Joey?

Win.  I just used this method on my framebag and I think it came out pretty good!