Sureau Sew-along: FBA (full bust adjustment) how-to

Today's post is for the ladies who wear a bra cup bigger than a C (although the Sureau dress might fit you if you are a D cup, you need to see for yourself by making a muslin).
The process is very similar to the SBA, and just as easy.

First off, determine how much you need to add to the pattern by subtracting the bust measurement corresponding to your size (that you can find on the size chart) to your actual bust measurement, and divide that by two.

1. Trace the pattern in a size that fits you in the shoulders and at the waist.
Trace a line going from the middle of the base of the dart to its point and extend it a few cm further. Measure 3 cm from the point of the dart and mark the spot. This is the center of the bust.

2. Draw a second line going from the center point you just marked to the middle of the shoulder.

3. Trace another line, joining the center of the bust and the center of the gathered area.

4. Draw one last horizontal line in any point of the area you see in the photo, as long as it is parallel to the horizontal line you traced earlier.

5. Cut along the lines you just traced, but not all the way. Leave some room to pivot the pieces at the shoulder and at the center of the bust.
Spread your pieces according to the measurement you got earlier. Keep the vertical pieces (where the dart was divided) as parallel as possible.
Use some tape to hold the pieces.

6. At this point, you can either put some paper under your pattern to fill the gaps you created, use some tape and cut around it, or, as I prefer, retrace your pattern piece using tracing paper.
Trace over the lines you spread at the side seam to obtain a bust dart.
Find the horizontal line you previously traced at the center of the bust and mark it on your new pattern piece.

Now measure 3 cm down the point you just marked, and you have your new dart point. Re-trace your dart using the old legs as reference.
And you're done!


The method I used is what I learnt from American books and blogs. If you're curious to see the slightly different French method, check out Eléonore's post. It's so interesting to see different approaches to pattern alteration!