Some pattern drafting….

We’ve been talking about taking a basic, really well-fitting t-shirt pattern and turning it into some sleeveless garments. This week we’ll talk about a racerback tank top with a shelf bra.

So, to make a racerback tank top, with a built in shelf bra no less, I took my basic t-shirt pattern and redrew the armholes and shoulder straps…

For the front bodice piece I knew I wanted my shoulder straps to be fairly slim and that I wanted the neck opening to be a wide scoop in the front. So I brought the shoulder straps in from both the neck opening and the armhole. Leaving me with about a 2 1/4 inch strap (including the seam allowances) I wanted the bottom of the armhole to be more open than in my regular tank top and so I scooped that area out as well about 3/4 of an inch or so, effectively lowering the armhole. And I brought the side seam in about 3/8 of an inch at the armhole only. For the back bodice piece I matched the shoulder seam with the front bodice piece and redrew the back neck opening to be a bit deeper than the original t-shirt pattern. I matched the bottom of the armhole with the new armhole I drafted for the front. I then determined how wide I wanted the fabric to be at the center back of the racerback. I marked that width (considering the seam allowance) and drew my curving sides from the new shoulder seam to the new armhole bottom.
** in my next version I will make the racerback more narrow.

For the shelf bra I traced out pattern pieces that matched the top portions of my front and back bodice pieces. I then measured down on my body to determine how much fabric I needed to go over my bust and marked that on my pattern and drew a line on my pattern pieces to indicate that. I wanted to finish the bottom edge of my shelf bra with a 5/8″ plush-backed elastic (found in bra making supplies) and so I added 5/8″ to that length and cut out my shelf bra pieces. Creating the shelf bra as a facing or lining, essentially, meant that I could cleanly finish both my armhole and neck opening with that fabric. Eliminating the need for any bands or binding.

I sewed the shoulder seams and the side seams on both my tank top and the lining/shelf bra, independently. I sewed my elastic, sized to fit snugly around my body below my bust, along the bottom edge of my lining/bra, easing it in as I went. Then I flipped the elastic up, towards the inside of the lining and top stitched it down, plush side towards my body.

Then I placed the right sides of the outer tank and the lining together and I sewed around my neck opening.

Finishing the armholes is sort of magical and somewhat hard to wrap your head around, but if you follow the steps, it works like a charm. With the shirt right side out, I reached inside, between the outer shirt and the lining/shelf bra, and pinched both seam allowances (folding them in) for the front armhole on one side (the armhole is sewn in two steps…front of the armhole and back of the armhole) in my fingers. I pulled my hand (and the seam allowances) back out through the shirt and sewed from the shoulder seam to the bottom of the armhole. Being very careful to only sew the seams. Then with the shirt still right side out, I repeated this for the back of the armhole. – I reached inside between outer shirt and the lining/shelf bra and pinched both seam allowances for the back armhole (folding them in) on that same side with my fingers. I pulled my hand (and the seam allowances) back out through the shirt and sewed from the shoulder seam to the bottom of the armhole. And did the same for the other arm. And “poof” I had finished armholes
…and a perfectly fitting racerback tank that I love!