Invisible Zipper Tutorial - Matching Horizontal Seams

Matching horizontal seams is one of the tricky things about inserting an invisible zipper. This often ruins the look of a garment in which much time and money has been invested, or is a dead give away that the garment was made by loving hands at home. How do you get those horizontal seams to line up? Here's how I get those seams match up.

Note: I prefer to insert the zipper before stitching the seam that the zipper is in. Just my preference. If you prefer to stitch the seam before inserting the zipper or would like to try it, please use El's tutorial found on the Sewing Divas blog - excellent tutorial and you're guaranteed to take away something useful even if you don't use the method exactly.

Preparation: Before you begin to insert the zipper, make sure you finish and/or grade the horizontal seam that you'll be crossing and clip the seam allowances diagonally at the corners. Reinforce the seam allowances with strips of fusible interfacing (5/8" wide and as long as the zipper).
Make sure that you have pressed the zipper, opening up the coil for easier and closer stitching.

If you are crossing a contrast band or two horizontal seams, make very, very certain that both sides are exactly the same width. If they are not, you will *never* get the seams to align and will be extremely frustrated. Careful planning, cutting and construction are important, as always.

Step 1: With the zipper open, hand baste, machine baste or pin the first side of zipper to the garment, aligning top edge of zipper with the top of garment. Stitch this side in place. You can see the machine basting and then regular stitching in the photo below. (BTW, isn't this zipper a terrible color match for the fabric? This is the best match I could find locally without ordering from NYC!)

Step 2: Close the zipper and find that horizontal seam. Using a pencil/fabric marker mark the position of the seam horizontally across both zipper tapes.

Step 3: Unzip the zipper and pin it to the other side, aligning the *horizontal seam first*, not the top. You can always trim the neck or top edge so that everything is even, if you need to.

Baste the zipper in place.

Now, zip the zipper closed and see if the seam matches. Looks good so far:

If it does not - remove the basting, reposition the zipper up or down and baste again. This may seem tedious but is the key to the whole process - *baste and check* before you sew it in permanently. It is better to remove basting now, than to be ripping out real stitches later! If it matches, go to step 4.

Step 4: Once the zipper is basted in place, with a long stitch machine baste the zipper in place, closer to the coils, but not where you would put the final stitching.

I find that once in a while, the zipper will shift a little bit between hand basting and final stitch, thus putting the seam out of a alignment by 1/16" to 1/8" - for many people this isn't a problem. I can't deal with it, so the second basting for me is necessary - might seem a little OCD to you, but it helps me. See what I mean about the shifting:

The seams don't match, so you know the drill: remove the basting and try again! It if matches, go to step 5.

Step 5: Sew the second side of the zipper in for real this time. Your seam should match or be really, really close to matching. After a second try, this is what I got, which is acceptable:

The remaining seam and zipper can be finished in the usual manner at this point.

That's it, really. There is nothing magical about the whole process. The whole process really relies on good old fashioned hand basting and patience to getting it right.

Parting Shot: Garden. Well, almost a garden. We still need to finish busting the sod in that last quadrant, rake, pick rocks and then think about plants. This is one of my son's summer projects, but for the moment, the three of us are working together to get it started.