How do you adjust bra cups to achieve a better fit? Today, we’re showing you how to adjust the cups of a bra.
Jump to another post in this series:
- Bra fitting guide overview
- How to choose your bra size
- How to make a test bra
- How to adjust the back band
- How to adjust the gore/bridge
- How to adjust the cups
- How to adjust the side seam angle
- How to adjust the straps
- How to adjust the underwires
- How to make an asymmetrical bra
- Additional bra making resources
The Cashmerette Willowdale Bra is a full frame underwire bra sewing pattern for large busts in sizes 28C-54J with a 4-piece cup design for vital support and lift in a beautifully rounded shape—the perfect bra if you have big boobs.
Start your bra fitting journey with the Cashmerette Bra Fitting Guide
To help you sew and fit your dream Willowdale, we’ve put together the Cashmerette Bra Fitting Guide! This post is one of the many tutorials you’ll find there, and if you haven’t yet checked out the main guide page, we recommend starting there. So much of bra fitting is interconnected, and the guide provides a checklist and order to work through the adjustments.
In this post, we’re covering how to adjust the cups of a bra to achieve a better fit. Let’s get started!
How to tell if you need to adjust the bra cups
For many sewists, the cup size recommended in the Willowdale Bra pattern will be a good match. (Find out how to choose your size here.) However, if you’ve made a muslin (test version) and the cup size doesn’t fit, you may see some of these issues:
A too-small cup size may be indicated by:
- Underwires sitting below the breast root (due to extra flesh in the cups pushing it down and out of place)
- Underwires digging in at the side
- Gaping underneath your breasts
- Extra flesh spilling out over the top of the cup
- Folds of flesh at the side of your breasts
A too-large cup size may be indicated by:
- Wrinkling in the cup fabric
- Gaping at the neckline
- Underwire sitting away from the breast root
If the overall bra is not fitting properly, you may need a different size. (Head to the Bra Fitting Guide for a fitting checklist.)
Important note: how cups fit depends greatly on the fabrics you are using, so make sure you test using the fabric and elastic you want on your final bra or make sure that the amount of stretch in the fabrics/elastic is exactly the same.
How to adjust the bra cups
If the bra cup on your muslin is too small, try going up a cup size. (If you’re already at the top of the cup range, use a sister size based on our instructions here.)
If the bra cup on your muslin is too big, try going down a cup size. (If you’re already at the bottom of the cup range, use a sister size based on our instructions here.)
Keep in mind that when you change a cup size, you’ll need to reprint the entire pattern since the band is also different, and you’ll be using a different wire size.
What if you don’t need an entirely different cup size, but just a few tweaks to make the cup fit you better? Here are a few adjustments you can make:
Remove excess fabric in the upper cup
Excess room in the upper cup usually shows up as wrinkles in the top half of the cup and gaping of the upper cup. To eliminate this excess fabric, pinch out the excess in line with the seam between the inner and lower cup and measure how much fabric needs to be removed at the top of the cup edge, at the upper cup seam and how far down the seam you need to go.
This example requires a ½” dart at the top of the upper cup (for a total of 1”removed), tapering to ¼” dart at the seam between the upper and lower cup, then further tapering to nothing at the bust point.
To apply this to the pattern, we will start with the upper cup piece. Draw a line from the notch on the lower edge of the upper cup, to the edge of the upper cup (dashed red line). Then draw in your darts lines symmetrically around this line. For this modification, we’re doing ½” on either side of the line at the top edge, tapering to ¼”on either side of the line at the bottom.
Cut along each of the solid red lines then join the two pattern pieces together
Smooth the curve at the join to get your new upper cup piece. Remember, in order to use the decorative edge of the lace along the top edge of the cup, that line needs to be straight.
After trying this on, you may find you have too much width in this piece now, which you can eliminate by bringing up the lower curve by the same amount at you did the top.
Next we need to modify the lower and inner cup pattern pieces. At the seam between the two pieces, trim away the corresponding edges, tapering from ¼” at the top of the seam to nothing at the bust notch (or as far down as you feel you need to go for a good fit).
Remove excess fabric in the lower cup
Excess room in the lower cup usually shows up as wrinkles in the bottom half of the cup.
To eliminate this excess fabric, pinch out the excess in line with the seam between the inner and lower cup, or the seam between the outer power bar and lower cup and transfer that to your pattern pieces:
Add or remove length in the lower cup
If the cup is too long or too short under the bust, determine the amount you need to add or remove by either slashing your existing bra cup and seeing how far it spreads or pinning out the excess fabric.
Then, mark your cup pieces as shown below and either spread the pattern by the required amount or overlap the pattern by the required amount.
Making up a new muslin
- Take out the stitches securing the underarm elastic at the seam between the band and the cup. You do not need to remove the underarm elastic fully—about 1/2″ on either side of the seam.
- Remove the underwire channeling
- Remove the cup from the band
- Cut the underarm elastic at the seam between the band and the cup—you want to try and keep as much elastic attached to the band as possible.
- Detach the strap from the top of the cup.
- Make up a cup in your new size.
- Apply underarm elastic to the underarm seam of the powerbar, stretching the elastic just slightly to fit
- Sew the new cup into the original band. Make sure that the two ends of the underarm elastic from the band and from the cup are sewn together so that there is still a continuous piece of elastic from the strap at the back to the top of the cup.
- Reattach the strap to the top of the new cup.