Hey mates, today I'll be showing you how I would do a FBA on the Carey Bustier
Do you need a Full Bust Adjustment?
There are a few ways to tell if you need to do an FBA. If your full bust measurement is larger than the full bust measurement that corresponds to your high bust measurement in the size chart. Also, if you've sewn a toile and there is tightness in the bust, the fabric is pulling forward at the front armhole, or there are drags lines radiating out from the bust.
The combined C/D cup has a 3.5in (9cm) difference between the high bust measurement and full bust measurement.
If you have determined you definitely need the FBA, you'll also need to calculate how much to add to your FBA.
First things first, find your size in the size chart using your high bust measurement.
Check the corresponding full bust measurements of that size. Calculate the difference between the largest full bust size available in your size and your actual full bust size.
Because the front pattern piece is based on half your body, you will need to divide the number by two – that’s how much you'll be adding to the pattern piece.
For example: These measurements below put the wearer in a size D, except for the full bust, which is an F. There is an extra 4in (10cm) between the full bust measurement for size D and size F. Half that is 2in (5cm). So they'd be cutting out size D and doing a FBA of 2in (5cm).
Before we start: If you're sewing View B
I'm going to show you how to do the FBA on View A. View A and View B have the same pattern pieces, except that View B has an extra seam line in the side front panels.
If you cut the seam allowance away on side front panel 1 and 2 (cut to the grey line), and place the panels together, they will be the same shape as the View A side front panel. Complete the FBA steps below, then at the end, cut the panels apart along the original line and add the seam allowance back.
Prepping the pattern pieces.
You will need your side front panel, centre front panel and top front pattern pieces.
Cut away your 1cm (3/8in) seam allowance from the pattern pieces. (This is already marked in a light grey line on your pattern.)
(For better visibility, the following diagrams will be illustrated using a black line instead of the pale grey line).
Flip the top front piece over and line up the seamlines and edges of the top front and side panel, as shown. Tape together. Draw on a continuation of the princess seam (green dashed line). Cut along this line.
Now we can do the full bust adjustment on these amended pieces.
Doing the bust adjustment:
Draw three lines on the side front panel.
Line 1 is a horizontal line across the pattern piece at the bust apex (the widest part of the bust).
Line 2 goes from the bust apex to the waist seam
Line 3 goes from the bust apex into the armhole.
Cut along lines 2 and 3. Try to leave a tiny hinge of paper at the bust point to keep these pieces together for now.
Starting from the side, cut through line 1 to the apex, leaving a hinge at the apex.
Tape segment (b) to a piece of paper. Swing the segments (a) and (d) out, keeping the hinge points together (blue arrows). Adjust segments (a), (c) and (d) until the gap (marked with red lines) is parallel and is the width you need for your FBA.
Once adjusted how you need, tape (a) and (c) down, and the top of (d).
6. Draw a horizontal line through the bottom of segment (d) (shown in green) and cut through it. Move the bottom of the piece down so that it is in line with the bottom of (c) and keeping the same parallel width as your FBA amount. Measure the length of the created vertical gap (gap 1) and write it down. Tape everything down.
Trace around the new pattern shape (shown in pink) and cut this out. Draw a line extending from the dart (shown in green) and cut along this line.
Close the dart, using the point (marked with a blue dot) as the hinge. Tape it down. This will create a small gap (gap 2) at the front. Measure this gap and write it down.
Place a small piece of paper under gap 2, tape it down and draw a smooth line connecting the edges of the gap (shown in green).
You will also notice that the waist measurement is now bigger than the original. You can leave that as is, if you prefer a less fitted bustier - or you can shave off the amount that was added as your FBA, from the side seams to bring it back to the original waist measurement. I've shaved off equal amounts from each side (shown in red).
Now we need to remove the top front section from the pattern piece. Draw a line to join this seam together smoothly (shown in blue). Cut along this line. Re-attach this section of the top front to the previously cut away centre portion of the top front piece.
Onto the centre front panel. We need to add the same amount of length to this piece, that was added to the side front panel. Draw lines on the centre front panel that correspond to where the side front panel was slashed and spread open. Cut along these lines.
Place a piece of paper behind the centre front panel and open the segments up, the same amount that the side front panel was opened up. Tape in place and draw on a new seamline, blending between the segments (green line). Measure the new seamlines on both pieces to make sure they are the same!
We now have three new pattern pieces that are looking pretty choppy with all the cuts and taped bits. Get a fresh piece of paper and draw around the outline of all three pieces, transferring the notches and grainlines. From this, we need to add the 1cm (3/8in) seam allowance back on (remember that you don't need to add seam allowance at the centre front fold).
If you're making View B, don't forget to cut the extra seamline in the side panel!
Cut these out and you're good to go! As always, I recommend making a toile before cutting into your good fabric, to check that these new mods fit the way you want.
Hope this helps
x Lauren