Halter Tank Top

I'm a sucker for patterns that match my measurements, and I’m always on the lookout for tank top patterns that use minimal fabric. If this one is made with a contrasting border (an opportunity both to slit the side seams and to use less main fabric) and even a contrasting back, it won’t use much of the main fabric at all. The contrasting border reduces the chance that the wrong side of the fabric will be seen, and the shelf bra does extra duty as a front facing and modesty lining. But rather than wing it entirely, I notice that it's similar to Belle Epoch Whimsy's tie tank top tutorial (I too would make it with buttonhole in front to tie there not at shoulders) which has excellent directions for a measure-then-draft pattern. The difference is that this has a lower back that's elasticized and sewn to (elasticized) shelf bra in front.

From Belle Epoch pattern drafting (except cut 1 for the front, not 2; use b-w-d-line trapezoid as pattern for the back and a-c-b-curve curved-side trapezoid as the shelf bra facing pattern -- BUT add seam allowance to back (upward) and facing (downward) on the 'b' edge so you may need to make three pattern pieces if you don't want to wing it too much), first measure yourself (in inches).

x = high bust

y = full bust

z = vertical distance between x and y

w = vertical distance between y and where you'd like the tank top to end

v = your (horizontal) body width at measurement point w

Then do some simple math:

a = THE SMALLER OF ( (x ÷ 4) + 1.5 ) AND ( b - 1 )

b = (y ÷ 4) + 3

c = z + 2

d = (v ÷ 4) + 4

Look at the pattern drafting directions from Belle Epoch for pattern drafting pictures -- a picture is worth a thousand words (or more in this case!).

Now armed with a pattern, make a strap (you can cut a skinny rectangle without a pattern, right? or use ribbon) and continue sewing from the Sewing Dork directions.

The pattern has IIRC 4 inches of ease, so it will be loose. But it's also a fitted-to-you pattern!