Horizontal bust darts give your knitwear a little extra length in the bust area so that the hem doesn't lift up to cover all the curves. Those of us with smaller bust sizes, like an A-Cup or below that, may find the bust darts unnecessary. With a B-Cup or larger, it can be worthwhile to incorporate the technique into the shirt. Generally speaking, however, everyone can benefit from bust darts. Yes, even an AA-Cup!
It also allows you to customize knits to fit different body shapes - because no two bodies are exactly the same. For example, you may have a very narrow waist, but your bust measurement doesn't fall into the same size category. With the bust darts, this can be adjusted a little better to your personal body shape.
To find the correct cup size needed for the horizontal bust darts, you'll need to measure your full bust circumference as well as underbust circumference. Take your full bust measurement along the fullest part in the same condition as you would like to wear your garment later: with or without bra. Pull the measuring tape around your ribcage, just underneath your breasts for your underbust circumference. Make sure the tape is running straight and level around your body.
You will now follow the calculations below to find your cup-size. While keeping to the system (CM or Inches) you are more comfortable with procceed as follows:
Cup Size in CM = (Full Bust measurement - Underbust measurement) / 3.75
Cup Size in Inches = (Full Bust measurement - Underbust measurement) / 1.5
Please note: In case the resulting value is a decimal then it must be rounded up or down according to the decimal’s value.
Use your result to find the number in the chart below that is closest to your value. This determines your cup size.
EXAMPLE:
Full Bust measurement: 95 cm | 37 inches
Underbust measurement: 77 cm | 30 inches
Calculation CM:
(95 cm - 77 cm) / 3.75 =
18 cm / 3.75 = 4.8 = rounded up 5
Calculation Inches:
(37" . 30") / 1.5 =
7" / 1.5 = 4.6 = rounded up 5
E | DD Cup
If you end up with a decimal of .5, you are right in between two cup sizes and can choose to go either for the bigger or smaller size.
Please note that is a Yarn Me Up sizing system and is not to be confused or compared with other industry standard sizing systems, which is why it might not sound familiar to you.
The horizontal bust darts should start at or just below the apex of the bust. This means that you should try on your knit to check this measurement. If it is already at the necessary length over your chest, you should start the bust darts immediately. Otherwise, continue to work in rounds according to the instructions until this length is met, and then pause there to work the bust darts. After that return back to the point in the pattern you paused at.
There are different ways to incorporate bust darts. In my patterns they are formed by using German Short Rows with double stitches. This technique makes it possible to add length to a knitted piece exclusively over a desired space without increasing the side measurement of the entire piece. This is done by turning the work at specific points. When turning, always slip the first stitch purlwise and pull the working yarn firmly back over the stitch. This distorts the stitch and creates something that looks like a double stitch. Then continue to work to the previous double stitch and a certain number of stitches beyond. At this point, the work is turned again and proceeded as before.
The different cups get different number of rows to match the cup sizes for this pattern.
If you are not familiar with the technique of German Short Rows with double stitches, check out my illustrated tutorial for them.
Click on the button below for the instructions on how to incorporate the bust darts into your Mika Tee, Mira Sweater and Fjord Tee: