Use this sewing pattern fitting tutorial to make a Fuller Bust Adjustment (FBA) to a raglan style top or jacket with a flat front, with no dart or other shaping, such as the Twig + Tale Loft Quilted Jacket.
This adjustment creates a dart for shaping and extra ease around the bust. Note that it is intended for those who need to increase the bust measurement by greater than two sizes. If you require a one to two size FBA (up to 4"/10cm), you may want to use this simplified tutorial for doing an FBA on a flat front, raglan-sleeved garment.
Materials
Gather some basic materials to adjust the pattern pieces:
- top/jacket Front pattern piece (we're using the Loft Quilted Jacket)
- measuring tape
- scrap paper
- tape
- ruler
- pen/pencil
- scissors
Measure
To determine the size of adjustment needed, measure your upper bust and full bust.
The upper bust measurement is taken around the body, with the tape snugged up to the underarms, above the breasts.
The full bust measurement is taken around the fullest part of the breasts.
Determine your base size from the Upper Bust measurement in the garment size chart. If your full bust measurement is two or more sizes larger than your upper bust measurement, use the Fuller Bust Adjustment (FBA) with a dart, as described in this tutorial.
Note: If your full bust is 1-2 sizes larger than your upper bust, refer to this tutorial instead: Fuller Bust Adjustment (FBA) for a Flat Front Raglan Garment - No Dart.
Calculate the difference between your actual full bust measurement and the full bust measurement in the size chart.
In our example, there is a 4" (10cm) difference.
We will divide the difference in half, since we will be working on half the front of the garment. So, in our example, we will add 2" (5cm) to the pattern piece. If you are doing a large adjustment, you may need to split the difference into two darts (described below).
Measure bust apex
Before adjusting your pattern pieces, compare your bust apex point with the bust apex point marked on the pattern. Everyone is different, so this will ensure you are adding the extra ease to the right place for your body.
To take the bust apex measurement, place the end of the measuring tape at your high shoulder point (about where your neck starts to curve away from the shoulder), then measure down to the fullest part of your bust. Note that the bust apex is not necessarily the same as your nipple position.
Be aware that the bust apex position depends on whether or not you wear supportive underwear (a bra). When taking your measurement, wear a similar undergarment to what you will wear with the finished garment.
To compare your measurement to the pattern, lay your measuring tape onto the pattern with the end of the tape 3/8" (1cm) from the neck point of the front and mark on the pattern where your bust apex falls. Mark this on the pattern and use this point as a reference for this adjustment. Here's an example:
Adjust pattern pieces
1. Draw a vertical line, parallel to the centre front, that runs from the raglan shoulder, through the bust apex point (as determined above), straight down to the hem. Draw a line, perpendicular to the first line, from the centre front to the bust apex. Then, draw a line from the bust apex to the side seam, angling it to a little bit below the armhole. Mark in the stitching line at the shoulder, 3/8" (1cm) from the edge.
Mark in the stitching line along the raglan seam, 3/8" (1cm) from the edge.
Cut along the vertical line from the hem, up to but not through the seam allowance at the shoulder, leaving a bit of paper intact to create a pivot point. Cut through the other lines.
Adding two darts
