Recently a student who was in our Swim Week class brought in a swimsuit she had purchased from a website in England. She paid a pretty penny (or should I say pence?) for this suit, not to mention the shipping, customs duty and the HST to get it here as well!
It's interesting enough, and i quickly saw that the bottom part could be made easily from princess version of our Denise swimsuit pattern PB-2901. The top part from just under the bust to the shoulder could be made from the Denise regular version, then the two sections could then be joined with a seam under the bust. In this case the seam also included a band of royal blue fabric with elastic inside.
But it wasn't the outside that was my student wanted help with, but the inside. Let's peek inside to see the interior support system.
This suit had a seamless underwired bra inside the suit. The fullness to accommodate the bust was achieved by gathers at the bottom of the wire curve. So it is seamless and not made from foam.
Want to see how ready-to-wear did this? I am happy to oblige...
First, we compared the wire size to the one in the original suit. Of course, if you know your wire size already, you are ahead of the game here!
Lets look at our Denise pattern again. Trace off the lining pattern piece, as we won't need the darted front. Now mark the position of the wire line on the pattern. The best way to do this is to mark the wire line height when the suit is on the body.
To make the cup pattern, on a separate piece of paper, draw a horizontal balance line with another perpendicular to it.On one side of the centre line draw a vertical line half the width of the bridge away from the vertical balance line. i show two lines here...ignore that line to the right of the vertical line!
Place the wire down so it touches the bottom line and the centre bridge line, trying to keep the "bowl" of the wire as even as possible.
Draw a 1/4" seam allowance around the wire line. It will likely touch the centre line. I continued the seam allowance straight up as well. You'll see why in a minute!
Measure down on each side to where the vertical arms of the wire start to curve in on the bottom. These will be the areas where no gathering will happen. The gathering will happen between the two notches along the bottom curve.Place the cup drawing on top of the lining drawing, matching the marked line on the lining to the marked balance line on the cup paper
Trace the drawing of the wire up to the armhole, and around the strap area and back to the centre front line. Trace a second copy of this shape and set it aside for the frame.
The first tracing is the cup shape, but in a flat form. We will now add the fullness for the bust. Draw lines from the "gathering area" up to the centre bottom of the strap. How many lines? Draw 1 line for each cup size, so a B cup would need 2 lines, D cup would be 4 lines and G cup in this case needed 7 lines. Distribute the lines as evenly as you can between the gathering space.
Cut to the point from the bottom on all lines
To help spread the lines for the gathers, draw two short lines to each side of the strap
Spread the lines 1" part (2.5 cm) measuring at the wire line. You will see the short lines acting as a hinge to allow the pattern to be spread apart
Connect on the outermost point of the dotted seam allowance as shown. This is where art meets engineering to make that bottom curve flow smoothly. It will still look weird though! Continue tracing around the strap.
Here's the finished cup piece, which will be cut on the fold at the centre front. Mark the gathering and no gathering areas and any other marks you may need. The cup pattern is finished so you can set it aside.
Lets go back to that second tracing and make the frame. Trace off the solid line of the wire , not the dotted line as this was the seam allowance for the cup. We won't need that.
Draw a seam allowance on the inside of the wire line, all the way up to the underarm. Then, draw a horizontal line under the frame drawing 1" down (more or less).Connect the top of the wire line to the CF line. The frame could be made from sheer cup lining as it was in the original or duoplex. You need something stable that will stand up to chlorine and dry quickly. Mark the fold line at the centre front.
Here's the frame cut from sheer cup lining.
Here is the gathered cup in the frame, partly finished as you can see. It's not quite finished but our student had to leave us! We were able to try it on her in a partly finished state and it was going to be a perfect fit!
Here's another look at the interior swim bra.
I hope you give this method of making a gathered seamless swim cup a try and let me know how you do with it. I would love to see pictures which you can share to our Facebook page (Bra-makers Supply - Beverly Johnson)