March 27, 2014

Yellow Polka Dot Bikini - Binding the Edges

The yellow polka dot bikini is almost done! In this post, join me as I share how I bind the edges of a foam cup (the triangle cups from Bra-makers Supply to be exact) without using any special machines, just an ordinary ol' straight stitch.

Cut some strips of spandex fabric at least 4 times the width of the finished binding you wish to have. It doesn't matter if the strip is wider, because we will trim it off later. But don't make it too narrow or it will cause you grief.

Stitch the binding strip to the front edge of the foam cup. Let the edge of the binding strip extend beyond the edge of the foam cup about 1/8" (3 mm). (You will see why in a moment) Stitch with a 1/4" seam from the foam side as shown here.

You can see the little edge better here. That happy face pattern weight belongs to Erin in our Swim Masters class! 

What's the reason for the little edge? Sometimes when you zig-zag the fabric to the foam, the fabric for the binding will show every lump and bump caused by the zig-zag. By having that extra fabric roll over the foam cup edge, it makes for a much nicer and smoother looking edge.

Roll the binding strip over to the inside of the foam cup and smooth it out over the edge of the foam cup. Pin it in place. Stitch-in-the-ditch in the well of the seam. That's a bit tricky but you can do it! There are special stitch-in-the-ditch feet you can get which makes a neater job of this but I find that sometimes they can "drag" spandex fabric and cause bias wrinkling. Not good. 

This is what it looks like from the outside

And from the inside.

Trim away the excess fabric with applique scissors or trimming scissors. Don't worry, spandex fabric won't fray. Here's the front edges of both cups finished.

Apply the binding to the other side edges in the same way. (The bottom edge will be treated differently). Let some fabric extend over the top. That's where we will fasten the rings that hold the straps.

Thread the fabric tail through a small ring and stitch it down to secure it. I have to admit, I did not like the look of machine stitching on this cup, so I hand stitched it securely. (well, I hope it will be secure!) 

You can see how close you can trim the binding to the stitching. Tomorrow, I'll share how I do the bottom band and our bikini will be able to go to the beach!


  1. I found this very helpful! I am making another bikini for someone (yellow too!) and I was looking for a better way to attach the binding.( I don't have a binding attachment to my cover stitcher). Thank you!

    1. Thank you! I am happy knowing I have helped in some small way. I love using the cover hem (with or without attachments) to do edges and straps