Bespoke Bras, Lingerie and Supplies

Tutorial - How to Alter the Bottom Cup Depth of the Labellum


We are very excited to about our latest bra pattern - the Labellum - with its longline option and modification instructions!

That said, we wanted to cover ONE method of increasing/decreasing the bottom cup depth (BCD) of the cups in detail and utilizing the “Layers” option in Adobe Reader. For those who are not aware, Adobe Reader is a FREE PDF Reader that is a bit more robust. The ability to turn on/off different sizes and/or seam allowance can make grading and customizing easier. While this tutorial was written for the Labellum specifically, the methods can be applied to any multi-pieced bra cup.


Here’s what it looks like as is. You will notice there are ALOT of lines. On the far left hand side, you will see an icon that looks like a stack of papers. Click on it and it will open up the layers.

If you click on the box before each size, it will turn on/off that size. Each size has 2 entries - one for the pattern piece and one for the seam allowance.


Simply turn on the size(s) you need and print. You can also turn off the seam allowance to make adjustments and grading easier.


In our previous sample [HERE], Heidi’s best fitting underwire fits 13.3cm/5.2” while her Horizontal Hemisphere (HH) is 14.9cm/5.9” and BCD is 12.5cm/4.9”. This means she needs the volume of the larger HH but a shorter BCD. We can accomodate that by reducing the BCD of the 14.9cm/5.9” to 12.5cm/4.9”.


Start with the Lower Center Cup (if using) as its the easiest. Simply draw a new slightly curved line at the smallest size.


For the other cup pieces, it is important to remember we are ONLY shortening the BCD and NOT the horizontal hemisphere. In essence, only the bottom cups of wireline. The left seam of the Lower Inner Cup is part of the horizontal measurement therefore, it DOES NOT change. Likewise, the lower right corner of the power bar is part of the horizontal measurement and also DOES NOT change.

You will notice there is no diagram for the upper cup - that’s because it doesn’t change!

In Heidi’s case, her underwire fits the 13.3cm/5.2” cradle the best. Its also a few sizes smaller than the 14.9cm/5.9” cup we just altered. Therefore, it is unlikely our altered 14.9cm/5.9” cup’s wireline will fit the wireline of the 13.3cm/5.2” cradle. There are 2 common methods to for fitting a larger cup into a smaller cradle: gathering or adding darts.

Depending on your situation, one maybe preferable to the other. I prefer incorporating darts into the seamlines. This method lends itself to dart incorporation quite nicely as you will see below.


All that is left is to “walk” the altered seamlines to make sure they all match up and add the seam allowance back on!


***If you need to reduce the BCD, below is ONE method of doing so. This happens to be my preferred method - flat drafting - simply because it suits how my brain functions. If this method doesn’t work well for your learning modality, you can try sewing up a size as-is and pinning/clipping the excess wrinkles then transfer to the pattern after.***