Measuring to Find your Sewing Bust Cup Size
Before you begin making a full bust adjustment, you’ll want to learn how to measure your bust to determine your sewing cup size.
The two measurements used to determine your sewing cup size are your full bust and high bust. Your full bust is the fullest part of your bust. To take this measurement, your tape measure should be parallel to the floor, try doing in front of a mirror. The high bust is the area of your chest right below your underarms.
A simple subtraction of your high bust from the full bust will give you the answer to your sewing cup size.
Just remember this is your sewing cup size and has nothing to do with bra fitting.
To find your sewing cup size you simply subtract your high bust measurement from your full bust measurement.
So a high bust of 36 and a full bust of 39 = 3 inch difference
The general rules for sewing cup sizes are as follows.
These are basic rules Not the law!
1 inch (2.5cm) difference = A cup
2 inch (5cm) difference = B cup
3 inch (7.5cm) difference = C cup
4 inch (10cm) difference = D cup
5 inch (12.5cm) = DD cup
6 inch (15cm) = E/F cup
7 inch (17.5cm) = G/H cup
If your full bust measures more than 3 inches (7.5cm) larger than your high bust, consider buying the dress pattern that closest fits your high bust measurement and then make the Full bust adjustment on your chosen pattern. This way the pattern will fit your neck, shoulders, back width and arm holes much better and you can make the bust adjustment on the pattern.
These diagrams show how the front body length increases or decreases when you have a larger or smaller bust than the pattern is graded for.
Remember the front body length also changes when the bust size increases. Most original vintage patterns are set for a B – C cup maximum.
The full bust adjustment tutorials will help you get the perfect fit by adding fullness just where you need it without distorting the other parts of your pattern.
Knowing that your dress sewing cup size can be different than your bra cup size will stop confusion. Dress sizing has over the years become more about marketing so dress sizes have changed to appeal to vanity and increase sales. Just as a shop size 20 in 1950 may now be a shop size 14 the same goes for bra sizing,. As such a DD cup bra from one brand can be a H cup in another. Sewing cup sizes are easier than bra sizes and will be more uniform across different pattern publishers as they are actual real human about body proportions so once you know your size it will be a constant to work with.
Its not complicated at all so don’t panic or be intimidated. But its worth making a few bodice templates in some basic designs so you can compare easily with new patterns you buy.
The most important thing is to get the best fit for your body shape and be proud and love your own creations.
Vintage or modern, daywear or evening glamour, a better fit will make you feel soooo good.
Bust position and shape can and will have a direct effect on your dress cup size. Uplift bras, or a 1950’s pointed bullet bra can give two very different shapes and measurements to the full bust line. So take your measurements wearing the undergarment you will wear with the project.
Note: Most vintage sewing patterns will be drafted for a b cup – small c up at most and will need full bust adjustments for larger cup sizes. Don’t let this put you off.