Multi-piece cups provide opportunities for shaping and support. However, the prospect of moving the strap to prevent a bra from sliding off your shoulders might have you scratching your head a bit. Here’s how to move the strap on any multi-piece bra cup. In the Pin-up Girls line, that includes Shelley and Judy, Freja and Frieda, as well as Ingrid. I am assuming you will want to move the strap toward the centre front; however, the same method can be used to move the strap outward as well.
The first thing is to decide how much to move the strap. I will assume you have made other bras and can judge how much the strap needs to move over. It’s really easy to see if you have the bra on. Ideally, the strap should create a line between the dip on the shoulder and your seam on the lower cup. You might need to move the strap 1/2″ to 1″, depending on your size.
I am showing the process on Ingrid, since that is the most complex of the 5 patterns. Rest assured, if you can do Ingrid, the others will be a walk in the park. Drawing at left below: First, trace off the upper cup (blue), the side panel (turquoise), and the front panel (pink) of the pattern with the seam allowances drawn in lightly. I find it very helpful to trace the pattern pieces using a different colour for each piece. I show the pattern piece outline as a solid line and the seam line as a dotted line. My dotted lines are quite visible, but I want yours drawn in lightly so they can be erased later.
Drawing right below: Tape the three pieces together as if they were sewn. Use the invisible “magic tape” if you have it. I find the shiny tape does not remove from paper easily, but the magic tape is much more cooperative. Don’t make the mistake of overlapping the pieces 1/4″ (6 mm), which is the width of the seam allowance. These pieces are actually overlapped 1/2″ (12 mm), so the seam lines are aligned. The pieces will look a bit odd at the cut-out section of the upper cup.
You can see how confusing all these lines get if they are visible, as in the left drawing below. Once the pieces are together, we can erase the seam lines shown at centre below. That’s the reason you drew them in lightly. Another alternative would be to cut the seam allowances off altogether and add them back when the alteration is complete. Drawing at right below: Draw a line parallel with the DoGS line of the upper cup. Stay in the armhole curve of the strap tab, but be sure to include the front panel. The sweet spot is roughly 1-2″ (2.5-5 cm) down from the top of the upper cup.
Drawing at left below: Cut the two sections apart. You now have an upper section and a lower section with enough tape to hold them together.
Drawing at right below: Slide the upper section along the line the desired amount toward the centre front. I want to move the strap by 5/8″ (15 mm). The pattern was drafted as the right-hand side of the body, so that means I’ll be sliding the upper section to the right by 5/8″ (1.5 cm). Slide it over by that amount (A). Tape the two sections together again. At this point, it probably looks like a jumbled mess of lines.
Now to reconnect the pieces. I connect lines from what I call “known point” to “known point.” That means connect the points on either side of the sliced line (points that haven’t been altered). You will find that you are going to cut off some of the original pattern on one side of the line, but you will be adding to the other side of the line. That’s exactly what we want.
Start with the upper cup, as it is the easiest. The bold lines are the new lines I am drawing. Join from the L-shaped cut-out to the curve along the front. Then join from the other side of the L-shaped cut-out to the bottom of the upper cup. Trace the new upper cup piece off.
Next, the power bar or side panel. The seam that connects to the upper cup is easy because that seam is a straight line. However, the armhole curve can be a little tricky. Use a French curve to draw a nice, neat curve between the shoulder point and the curve at the bottom.
If you were moving the strap on Freja, Frieda, Shelley, or Judy, your work is done. On Ingrid, however, you still have the front panel to do. Join from the point at the top to the centre front seam. Join from the same point to the start of the curved area of the front panel.
Here are the new pattern pieces compared to the original. The modified piece is the bold line. You can see how the top of the pattern piece has shifted 5/8″ (15 mm) to the right, while the bottom of the piece did not move.
If you need to move the strap on any multi-piece cup, I hope you will find this information helpful.
