Don McCunn's Blog

Changing One Dart to Two

July 3, 2010 on 12:02 am | In Fitting Issues, Pattern Design Guides, pattern making | No Comments

I am working on a design concept for custom-fit bras based on the Bust Sling from my eBook How to Make Custom-Fit Bras. This design lends itself quite naturally to a bra for nursing mothers. A neighbor of mine is about to give birth to her second child. She has graciously agreed to test this concept for a bra. She has indicated that she prefers nursing bras that have foam in the covering portion of the cup.

As I was developing the pattern for the foam for this design I found it was going to have a rather large dart. In the past we have discussed in my group How to Make Sewing Patterns the problems of darts for women with larger cup sizes. They can become quite pointy.

I decided to tackle the problem of changing one dart to two for this particular design. I wasn’t sure how to best approach keeping the shape while changing the dart. I like to advocate the use of poster board to test out pattern shapes. Particularly for the complex curves of bra patterns. The photo below shows the evolution of changing a single dart to two darts.

Here are the steps I followed:

1. The first photo shows the shape of the pattern for foam with a single dart.
2. I wanted to spread the distance between the two darts based on the Bust Circle which I describe on page 58 of my book How to Make Sewing Patterns. I opted to spread the darts by 5/8″ to either side of the existing dart. Those are the two pencil lines in the second pattern that are parallel to the sides of the dart.
3. I taped the single dart in the poster board closed, then cut along the two lines from the step above. I flattened the poster board.
4. When I made this pattern I discovered that the bottom curve of the pattern needed to be adjusted slightly when the poster board was flattened. Both the body and fabric have give. This minor change in the shape of the pattern does not concern me. I show this adjustment to the pattern with the red line in the fourth pattern above.

The last two images compare the poster board shapes of the one dart and two dart shapes. I was pleased enough with the results that I decided to make them up using the swimsuit techniques I describe in my eBook How to Make Bikinis and Bandeaux.

The final test will be to see which of these two styles looks best on my neighbor with her input being crucial to the final decision. I am intrigued by the process of exploring pattern shapes as a collaborative process with the person who will wear the final garment. I recommend that if you follow this procedure, you take it in the kind of small steps I have indicated here. I would be very hesitant to change my concept if this was the final product. But it isn’t. It is just one small step in a larger process.

If you are interested in learning more about the evolution of this particular design, I am sharing the process with my Yahoo group How to Make Custom-Fit Bras.