Did you know that most sewing patterns are drafted for a B or C cup size bust (with a few exceptions like Cashmerette Patterns which go up to an H!) , but the average woman is a DD? But don’t worry – it’s possible to adjust any sewing pattern to make the bust size bigger, in a few steps, using a Full Bust Adjustment.
This tutorial is specifically for dresses or tops that don’t already have a dart in them, so it adds the space you need as well as a new dart. It works for patterns like the Sewaholic Belcarra Blouse, the Megan Nielsen Eucalypt top/dress, or the Grainline Scout.
1. Calculate how much additional width you need through the bust.
The quickest way to do this is to measure your bust, and work out how much bigger it is than the pattern. Then, divide that by two (because you’ll be adjusting both sides!). An alternative way is to measure your high bust and use the pattern from that size, and then add the difference between your full bust and high bust.
2. Mark your apex on the pattern.
Yeah, your apex is your nipple (cue my Google searches going mental). Place the pattern against yourself, making sure the shoulder and side seams are in the right place, and mark it on the pattern.
3. Mark three lines coming out of the apex The first one should go from the apex up to the armhole, about 1/3 of the way up. The second should go vertically straight down the pattern from the apex. And the third goes at a gentle angle toward the side seam (you can just judge the angle by eye).
4. Start cutting and spreading!
– Cut up the vertical line, angling at the apex to the line that goes to the armhole. However, make sure you stop just before the seam allowance (usually 5/8 inch in). Then make a little snip on the other side of the seam allowance, forming a hinge
– Then, cut the line from the side seam to the apex, and again stop just before the apex to form a little hinge
– Either pin or tape down the right hand side bit of the pattern
– Now “spread” the other pieces to the left, keeping the vertical pieces parallel. Separate the vertical pieces to the additional width that you need to add. As you do this, a dart will start forming magically at the side seam!
5. True up the length
You’ll notice that the pattern is no longer lined up at the bottom. To address this, make a horizontal cut in the right hand side piece (it doesn’t matter where), and slide that piece down so that the bottom is parallel again.
6. Trace that baby!
Put some tracing paper over the chopped up pattern and trace the new outline. The triangle at the side seam is your new dart. Depending on how much you added, you may also need to re-draw the armhole using a French curve to get it back to the right shape.
7. And here we are! The adjusted piece. Sew up the dart before you sew up the rest of the dress, and the Tank Dress will suit you oh so much better!
I hope you found this helpful – I have to FBA almost all my patterns, so I can tell you it only takes a few minutes when you have some practice!