All About Power Bars (IV): Drafting and Sewing the Seamed Power Bar

Hi guys! Today I present you the last part of my powerbar series!! You can read here the first part (general information about the power bars), the second part (about internal power bars) and the third part (about external power bars). This fourth part is going to be about drafting and sewing the seamed power bar! It’s a very popular style that allows for lots of variations, so let’s begin!


Drafting the Seamed power bar

We’ll start drafting the same way as we did with the internal and external power bar: overlapping the cup pieces so the seamlines are on top of each other. We also need to mark the apex of the cup and the point halfway the underarm edge and the apex.

Now, you can start drawing your power bar from the strap attachment (or anywhere near it) but you can do different shapes: a straight line similar to what we did on the internal power bar, or a curved line with an S shape, a C shape or a D shape:

External Power bar drafting - C shaped power bar

All these lines should pass near the halfway point between the underarm and the apex, and they should end near the mark that is below the apex at the lower cup. Also, if you want to draft an S curve or a C curve, be careful and don’t bring the line too close to the underarm edge: remember that you’ll sew an elastic trim at the underarm, so if you got too close you won’t have enough space to sew it!

External Power bar drafting - S shaped power bar

Next, trace your pattern pieces on a different sheet of paper and add seam allowances to them. Mark a notch on your power bar to indicate the point where the cup seam would cross: it will help you to match the pieces when you’re sewing it to the rest of the cup. You have your new bra cup ready!

External Power bar drafting - D shaped power bar

Cutting the seamed power bar

Cut the new pattern pieces that you’ve drafted as usual, and remember that the DOGS (Direction of Greatest Stretch) at the power bar piece go parallel to the strap attachment line.

Seamed Power bar drafting - dogs

Sewing the seamed power bar

As with the internal and external power bars, you have to sew the lower cup to the upper cup first. Then match this seam to the notch you marked earlier on your power bar piece. After that you can sew the power bar to the rest of the cup and topstitch if you want to. The construction of the rest of the bra goes as usual. We’re finished here!

Seamed Power bar Sewing - C shaped power bar

I hope this whole power bar series had been useful to you! If you have any questions or comments, they’re more than welcome! 😉 Now, I leave you with some bra-inspiration with power bars. See you next time!

HEIDI KLUM – Opal Dream Contour Balconnet Bra – Image via Heidi Klum
ELSE – Signature Silk & Lace Underwire Balcony Cut Out Bra – Image via Else
PRIMADONNA – Deauville Bra – Image via Glamouse
PRIMADONNA – Madison Bra – Image via Glamuse
ELSE – Signature Giverny Underwire Longline Bra – Image via Journelle
BERLEI – Beauty Curve Full Cup Bra – Image via Journelle


  1. Hi
    I was wondering if the shape of the seamed power bra affected the fit or final shape of the bra?

  2. Hi Karen! That’s a really good question!
    I believe that the overall effect is more or less the same, wether you use a C power bar, an S power bar or a D power bar. Nevertheless, the width of the power bar does have an effect on the fit: if your power bar is too narrow, it will have less “power” to do its thing (e.g. push the breast tissue forward). I hope this could help to answer your question! 🙂

  3. Thanks Karen for asking that question. Thank you Silver Lining for the answer as it was just what I was looking for after just scanning all the lessons. I really appreciate this info as I made the normal bra from Beverly Johnson’s class and am not happy with it at all. I wanted my breast tissue to be away from my arm so it wouldn’t constantly be hitting it. I didn’t get clear understand and now I do. I so greatly appreciate this sight and I will be a constant member. Thank you again.
    God Bless you.

Leave a Reply to Janis Bowman Cancel reply