Q&A

PLUS-SIZE SEWING
By Barbara Deckert

I'm a GG cup. The Sept. '06 column said to purchase a pattern according to the upper chest measurement, and then adjust the cup size if you're larger than a B cup. How do you make that adjustment for my size?
Katie M.,
e-mail

Depending on individual styles and sizes, there are many ways to enlarge cup size on patterns, but the theory behind these adjustments is the same–it's all geometry. The shape of a breast is basically half a sphere, and the fabric that covers it is basically a circle. A girl with no development could wear two flat circles on her chest and they would "fit." To fit a breast, you have to cut a sector out of the circle, just like cutting out a slice of pie. If you bring the cut edges together, it makes a cone shape. The bigger the cut sector, the more the cone will protrude, and the bigger the circle, the greater volume the cone will hold (1). As cup size increases, the width and the length of the area that covers the breast must increase, as well as the dart.

For a basic bodice with side seams and waist darts drafted for a B cup, draw a vertical line from the waist-dart center through the apex mark up to, but not through, the shoulder seam. Draw a horizontal line through the side-seam dart and through the apex from side seam to center front. Slash and spread both horizontally and vertically about one inch per cup size larger than a B. For a GG cup, also known as an H cup, spread six inches horizontally and vertically. Tape the adjustments to a tissue underlay, and redraw the darts (2).



The additional-inch-per-cup size rule is a basic guideline; any excess width and length can generally be pinned out at the seams during fitting. The circle diameter is much bigger for a size 32 than for a size four, so the actual dimensions of the drafting of an H cup and the way it looks on a paper pattern for a small-framed woman is different from that of a large-framed woman. All bust adjustments need to be fitted on the figure, and radical adjustments should be tested in muslin.

Very large cup size adjustments result in very large darts. To reduce bulk, divide the darts as if you're taking two or more small pieces out of the pie instead of one big one. Or, hide darts in design features, such as princess seams, gathers, tucks and yokes. Adjust hidden darts for cup size by drafting additional darts into the pattern pieces. For example, a side-seam dart drafted into the side front of a princess-seamed garment accommodates bust fullness but is hardly noticeable when your arms are down.

Large-Bust Style Basics:

• Always wear a supportive bra.
• Avoid chest pockets at all costs.
• Choose dark, solid colors–no stripes or patterns!
• Select patterns with open collars or V-necks.
• Avoid closefitting fabrics like stretch knit or spandex.
• Choose a singlebreasted blazer that comes in at the waist.

Barbara Deckert writes more about dart adjustments in Sewing for Plus Sizes: Design, Fit and Construction for Ample Apparel. She's also authored Sewing 911: Practical and Creative Rescues for Sewing Emergencies, both from The Taunton Press. Barbara is a custom dressmaker in Elkridge, MD.

From the January 2007 issue of Sew News magazine.