How to Transform Your Vertical Princess Seam

If you’re tired of the same old look, try out this method for transforming your vertical princess seams into diagonal seams across your molded bra cup. Sometimes, different style lines are all you need to embellish your design portfolio.

This method is a direct application of a wonderful bra tutorial from Amy Chapman of Cloth Habit for transforming a diagonal seam line into a vertical one.

The method that I’ll be showing here uses the MIKO Beginner molded bra cup pattern, which is a vertical princess seam pattern, and transforms it into a diagonal seam.

Let the Transformation Begin:

1/ Identify and mark the apex on the Front Cup and Side Cup. The apex is at the center of the notches.

2/ The seam allowance (SA) along the princess seam is 1/4″. Measure the SA and cut it off of each piece.

3/ Slide the Front Cup and Side Cup together (along the same alignment as the DoGS) until the apices meet. I recommend doing this step over a large piece of drafting paper. After sliding your pieces together, tape down your Side Cup.

4/ Starting approximately one inch above the bottom left corner of the front cup, draw a line through the apex and roughly to the middle of the Side Cup’s right edge. Then, using a ruler and X-Acto knife, cut your pieces through that line.

5/ Pivot the top Front Cup piece to the top Side Cup piece, essentially closing the dart. Tape the top pieces together, then repeat for the bottom pieces.

6/ Re-establish the apices of the newly formed top and bottom pieces.

7/ Using a French curve or hip curve ruler, smooth out each piece through the apex.

8/ Trim away excess sharp points.

9/ Finally, re-draw your 1/4″ seam allowances, then mark the apex of each piece with a notch or slit.

Important Note

This alteration will not result in equivalent lengths between the upper and lower pieces. When you’re ready to sew your pieces together, pin your apices together. Then, allow the curve of the top piece to follow the curve of the bottom piece, pinning as you follow.

To apply your new fabric cup to your molded cup, simply align the apex of the fabric cup with that of the molded cup. Then, just like the original method, stretch the fabric over the cup and clip as you stretch. Check out this method below:

After attaching the fabric to the cup, the rest of the process is exactly the same as the original pattern.

Examples

I wanted to explore this method because a client requested a suit that represented her country’s colors. This was by far one of my most favorite challenges resulting in one of my most favorite suits.

This method will also serve as a great scrap buster. If you’re anything like me, parting with a piece of fabric scrap is irrationally difficult. So, I like finding ways of using up every last square inch.

The more you play around with this method, the more you’ll learn that you can manipulate the seams in any way you want!

If you’ve experimented with new style lines, please do share you makes in the DIY Bikini Facebook group! Your work will inspire the creativity in all of us!

I’ll talk to you soon.

xo,

Monica