I’m so excited to share with you a fun and easy t-shirt transformation project! As I am a huge lover of versatile garments, this tutorial can also be used to make a bikini, bralette, or a triangle cup crop top, like I did here.
Before we begin, be sure to tag me on Instagram @sew_zune or share your pictures on the Zune’s Sewing Therapy Facebook. I’d love to see your finished project!
Let’s get started…
For this triangle cup halter crop top, we will be making 2 simple pattern pieces, the cup and torso.
1a. Measure the width of the cup from the side seam to the center of chest. Also measure the length of the cup. Mine was 8” x 7”.
1b. Measure the underbust and the waist, and subtract about 1.5”~2” depending on how stretchy your t-shirt is. You want this torso piece to be snug or the back will sag so you may have to take it in more later. Then measure the desired length of your side seam.
2a. Let’s start drafting by making a simple triangle! Fold a piece of paper in half and draw a line that is HALF of your cup’s width. Then draw in the cup’s length measurement.
2b. Measure down 3/4” from the first line and draw a short line about 1/2” long. Then curve up to meet the end of the first line.
2c. Add your seam allowance and cut out 4 pieces.
3a. Make the torso pattern using the underbust, waist, and side seam measurements.
3b. If you’re using the original hem from the t-shirt, simply fold up your pattern’s hem allowance.
3c. Close the sides with a zig zag stitch or a serger. You may want to try it on and adjust if necessary before attaching the cups. Since it’s a backless top with nothing holding up the back, the torso needs to be snug or the back will be sagging.
4a. For the straps, cut 2 strips that are 2” wide and fold each strip in half lengthwise. Sew with a 1/4” seam allowance using a zig zag stitch.
4b. Turn the strap right side out by using a safety pin. Press with a warm iron making sure the seam line is in the center. Let’s call this the WRONG side of the strap.
4c. Fold one end of strap and stitch it down. Then clip close to the seam.
5a. Place the RIGHT side of the strap on the RIGHT side of the cup piece, extending the strap a little past the cup’s point.
5b. Place the RIGHT side of another cup on top of the first, sandwiching the strap. Stitch only the 2 straight sides with a zig zag stitch.
5c. Overlap the 2 cup pieces 1.5” and baste within the seam allowance.
6a. Fold the basted cups in half and mark the center. Also fold the torso piece in half and mark the center.
6b. Matching the midpoints of the cups and the torso, stitch with a zig zag stitch or serger. Be sure to have the cup’s end flushed to the torso’s side seam. The cup may be larger than the torso’s front, just stretch the torso piece as you stitch it to the cup.
6c. Fold the back seam allowance under and stitch with a narrow zig zag stitch.
Your DIY t-shirt transformation is now complete! And now that you have your own custom pattern, you can use it to make yourself a bralette or a bikini.
Also, if you have any gaping issues, be sure to check out this quick tutorial on how to fix it easily.
Sew long and be happy! 🙂