INCREASING A BUST DART SIZE
Patterns such as Cecily Dress by Sewgirl, are usually made for a bust size B, so if you need to increase the size, you will need to make an adjustment known as a full bust adjustment (FBA). You will need to add on the following according to your bust cup size:
AA cup= reduce by 1cm. A cup= reduce by 6mm. B cup= NO CHANGE.
C cup= add 1cm. D cup = add 1.9cm. DD cup= add 3.2cm.
1. Draw three lines as shown by the red in the picture A, B and C (below)
Line A extends from the Apex point* vertically to the lower edge.
Line B extends from the Apex point to a point a third of the way up on the lower armhole.
Line C extends from the Apex point to the side seam through the middle of the leg of the dart.
2. Cut the lines as follows:
Line A cut from the apex to the lower edge.
Line B cut from the apex to the armhole edge but stop a few millimetres before the edge.
Line C cut from the side seam to the apex but stop a few millimetres before the apex.
3. Spread the pieces apart adding on extra, according to your cup size shown above in the size guide.
Cut a line across perpendicular to the line A, move so the pattern is aligned at the lower edge. Place a piece of paper behind each open section and tape in position.
This is now an increased bust dart.
REDUCING A BUST DART SIZE
For cup sizes AA and A, you will need to reduce the size of the dart according to the measurements in the Size guide above. Instead of open the sections A, B and C you will need to close them, overlapping the pattern as shown below.