Here are a couple more questions I've received about swimsuits that I'm answering for everyone. These happen to be about making straps.
1. Do you ever make separate straps and then sew them on, or do you always just make the suits where the straps are a continuation of the suit?
Usually, I don't add separate straps. I prefer the contrasting binding to flow into a continuous strap. The only time I've made a separate strap and attached it to a suit is when I've done the One-Shoulder swimsuit for my daughter.
However, with that being said, here are the basics to making a strap that you attach separately to a swimsuit top.
double or Twin needle then use something like a multi-zigzag stitch as your topstitch. It may also be called a Three-Step zigzag.
2. Do you put elastic around the top edges of swimsuits when attaching separate straps? I.E. like the suits shown on pattern McCalls 4818
Yes, you would put elastic around the entire upper edge of the tankini (or swimsuit). You cut and position an elastic piece for the front edge. And then another elastic piece for the back and armholes section. Then flip it over to the inside just like you would do on any other elastic edge.
And then if you are making a shorter tankini you would also put elastic around the lower edge as well to keep it in place. When I make the longer tankinis I don't put elastic around the bottom edge. My girls like their tankini tops to hit a couple inches below their waistline--I usually cut the pattern piece so that the hem is even with the top edge of the leg opening. Always cut longer if you are able--you can always shorten it up if the girl prefers it. Not so easy to add onto if they want it longer.