How to Attach Elastic to a Bikini Bottom – No serger needed!

HOW TO SEW WLASTICS TO A BIKINI

If you are reading this post, chances are you would like to learn how to make your own swimsuit.  Imagine yourself being able to choose the colors and silhouette, unleashing your creativity!  If you are different sizes in the top and the bottom, that wouldn’t be a problem either, you would just cut the corresponding sizes.  But in order to make a swimsuit that looks store bought, you will need to attach elastic properly.  You could do that using an industrial sewing machine, like an overlock/serger, but that means investing a few thousand dollars.  For those of you that would just like to be able to sew your own swimsuit, good news: you can do it, no overlock/serger, or fancy equipment needed!

 

When I started sewing swimwear 17 years ago, I struggled to find the right swimwear elastic.  I tried a variety of types and sizes, and wasted time and money.  If the elastic is too stiff, the final appearance will not be appealing, if the elastic is to wide or thin, it won’t do the job of holding the garment together without puckering or pinching. I recommend using 3/8 inch (1 cm) braided elastic (shown).  It is soft, easy to attach and the size and width are the ideal ones, trust me.  Click below for details:

 

You will only need a domestic sewing machine with zig-zag stitching with ball point needles.  To get a good fit, the elastic should be a bit smaller than the opening you will be sewing it in.  If you are using a sewing pattern, follow the instructions for the elastic length.  My pattern shop has three styles of swimwear patterns, ideal for beginners.  They come with step-by-step pictures and instructions in English and Spanish.  I also have elastics, cord ends and pattern kit that include everything needed to make a swimsuit just for you!

 

If you are not using a pattern, this is my suggestion: Measure the size of the opening where you will sew the elastic (waist area, leg openings, etc.).  Subtract 1” to that amount and presto!   With this reduction and the overlap when you attach it, the elastic will fit properly, without too much gathering.

Cut the elastics in the corresponding lengths. Lap ends of elastic 1/2” (1.25 cm) and stitch securely.  Divide elastic into quarters and mark.  Do the same with the waist and leg openings. (FIG. 2)

 FIG. 2

FIG. 2

On waist and legs, pin elastic to WRONG SIDE, matching quarter marks and stretching elastic to fit.  With elastic on top, sew using a short, wide zig-zag (you want this stitch really wide, but short, so it resembles an overlock/serger stitch). Stitch as close as possible to the outer border of the elastic.  Make sure to pin the beginning and end of the elastic to the beginning and end of the sides, stretch elastic as needed. (FIG. 3)

 FIG. 3

FIG. 3

Turn elastic to INSIDE (where you stitched the elastic).  Top stitch elastic with a medium zig-zag ¼” (6mm) from fold, stretching as you stitch.  This zig-zag stitch is different from the previous one, you want it to be medium width and medium length.  Keep fabric pulled taut over edge of elastic, making sure to stitch as close as possible to the inner corner of the elastic. (FIG. 4)

 FIG. 4

FIG. 4

The final result should look something like this (FIG.5).  Remember that practice makes perfect and enjoy the process!

 FIG. 5

FIG. 5

I sewed this bottom using the Stella Bikini Pattern, available here:

To make this swimsuit, I used the Janome 8077 Computerized Sewing Machine (click on the image below).  I really liked this machine, for a few things: You can select a specific width and length for the zigzag stitch.  This is great because I used different length and widths to attach the elastic, to join pieces and and to topstitch.  You can adjust the speed so if you are sewing difficult curves or you are just a beginner, setting it in the slowest speed will help.  Also, it has several automatic buttonholes, automatic needle threader and lots of decorative stitches.  Finally, you can operate the machine using the pedal or with the touch of a button!

Ready to make your first swimsuit? Try this free PDF Instant Download Sewing Pattern.  It comes with printing and sewing instructions in English and Spanish. Click here to get it!

Please comment below and let me know what you think about my post. I would really appreciate if you share this post with a friend that might find it helpful.
xoxo,
- Tommie