The Bandeau Bikini Top
What Are Stretch Textiles Made of?
For what appears to be a simple strip of fabric, this strapless design is a favourite and timeless classic.
The photo on the left below is from 2002, and was beaded to match the necklace. This one was darted under the bust for a D cup .... you really only need to consider adding darting to a bandeau if you are making for a C+ cup bust. If you do insert underbust darting or gathering at the side seam, then you will also need to bone the side seam (as in this example) to keep it from collapsing vertically.
The middle photo is a dart-less bandeau without side boning. I also curved the top and bottom lines of the bandeau and made it narrower overall. I'll demonstrate how to make this style first. The last photo is actually a variation of the bandeau in which its cut down the center and a draw-string added. I'll also show how to adapt the bandeau pattern to make this style at the end.
All photos by Chris Huzzard, All swimsuits by me.
Draft a rectangle half the bust measurement x 0.88 minus 4cm (extra reduction due to the decreased height of the panel) by 12cm high (between 10cm and 14cm - simple design preference). Mark in a horizontal line halfway up the rectangle, representing the bust line. Mark in the bust point at half BP to BP x 0.88 from the right hand side of the rectangle (centre front). At the left hand side of the rectangle (centre back) mark a point 3cm above and below the bust line.
Draft in the top of the bandeau as a gradual curve from centre front down to the centre back guide. There shouldn't be any significant reduction in height until you begin to pass the bust point. You could initially contour the top and bottom lines a little toward the bust line at centre front as in my middle photo, at the beginning of this demonstration (not done here). Place the side seam in the middle of the rectangle or up to 1cm toward the centre back of the middle if you want to balance things a little better on the body. The exact middle sits better on the retail shelf.
Separate the front from the back. Remove unnecessary guidelines. If necessary retrace the front and back panels.
Make a mirrored copy of both front and back pieces. Place the two front pieces together at the center front and do the same with the back pieces. Remove unnecessary guide lines. Add seam allowance to the pattern based on how you intend to assemble it. I've shown this pattern with 10mm allowance for overlocked seams (8mm to blade plus 2mm off cut) and 10mm allowance for folding over 9mm elastic. Finally, be sure to clearly label your pattern pieces with a title, panel name, garment size, cutting instructions, author’s name, date and revision number.
To modify the pattern for the draw string bandeau we go back to the end of step 2.
Narrow the height at the centre back to 2cm so we can put one of those little bikini clips into. Draft a vertical guide through the bust point. Draft a second vertical guide 2cm in from the centre front. This represents a gap at the centre front of 4cm ... you could make this gap wider on smaller busts for a sexier look. Divide the space between the vertical guides into quarters as illustrated.
Draft in the top and bottom bandeau lines allowing for the width of the bikini clip (1cm for 2cm wide miniclip - yes there's varying widths so pay attention). While the side seam is shown here, I wouldn't bother with it, instead making the pattern a single panel. This way it can be turned 90 degrees and worn as a halter by some people .... yes people really do that!
Slash and open the panel out to as much as you like to see in the gathers. I am not big on gathers in swimwear as I don't like how they mess up tension lines so I would only open it up until it formed a nice line with the rest of the panel as shown. Also don't forget to take a further 2cm out of the centre back because the strap is narrowed.
Remove unnecessary guidelines. If necessary retrace the front and back panels. Add seam allowance to the pattern based on how you intend to assemble it. I've shown this pattern with 10mm allowance for folding over 9mm elastic, with 20mm allowance for a fold over casing with overlocked edge, and 20mm at CB for the fold over into the bikini clip. Most industry would simply straight stitch the casing down from the inside assuming it doesn't need to stretch. I prefer to chain stitch from the outside because I'm not in such a hurry.
If you were to use a binder attachment to apply the elastic and casing fabric to the edge, then you wouldn’t need any seam allowance on those particular seams. Finally, be sure to clearly label your pattern pieces with a title, panel name, garment size, cutting instructions, author’s name, date and revision number.