Bust Sling Bras & Garments

About the Bust Sling Bra

The Bust Sling Bra is a custom fit bespoke bra that can be made by anyone with minimal sewing experience. The instructions for creating the bra are in the book How to Make Custom-Fit Bras & Lingerie and the free online Patternmaking Classes. These bras and garments are made for the body of a specific individual. The are not ready-to-wear bras or garments you can purchase. Don McCunn designed this style of bra partly as a result of comments in his bespoke pattern design class when women said "I feel like I need sky hooks to hold my girls up."

Bra Comparison

In the images above all the bras are worn by the same model. The red lines indicate the full bust level relative to the natural waist for each of the bras. The one on the left is a ready-to-wear designed for a comfortable fit with no supporting underwire. The middle three ready-to-wear bras use a combination of underwire and foam cups. The one on the right is a bespoke Bust Sling Bra.

The Bust Sling Bra uses non-stretch fabric, no underwire, and only enough tension around the rib cage from elastic to accommodate breathing. Changes in day-to-day breast sizes are accomodated by the soft tissue rising and falling inside the bust sling without affecting the overall fit.

Bust Sling Garments

In addition to the bras a skirt can be added to the bottom of the bra to create dresses, gowns, and even wedding dresses that require no additional undergarment.

Red Dress Black and Gold Dress Blue Gown Wedding Dress

The Concept

The conventional bra is based on a cantilever concept where the weight of the breast is supported by the band around the rib cage. The Bust Sling Bra changes the support structure to a suspension style that follows the natural contours of the body.

This style bra has been developed in large part to provide support and comfort for women requiring larger cup sizes. The model in the photos below was instrumental in the development of this bra as an initial fitting model then as a field tester. She wears an "H" cup in an conventional bra. While the bra is designed to provide both coverage and support, this model's soft tissue is mostly self-supporting requiring minimal support as you can see in the nsfw image "The Conversation" from Don McCunn's Revisiting the Classics.

Bra Comparison

Back Support Structures

The back of the Bust Sling Bra can be styled to optimize the comfort and design aesthetic of the wearer. For example, the back support can be: a halter neck; "X" back; or racerback to mention a few.

Bust Sling Bra back variations.

What Women Are Saying About the Book & Bra

"I made one of the test bra slings. I am happy to report that it is the most comfortable bra I wear. I wear it every chance I get. My girls are on the large side and the bra sling gives me great support, and lift."

Becky Hess

"I bought this book with 4 others to learn how to sew bras, specifically for my daughter who is a 48F. She has had a lot of problems finding properly fitting bras since Covid-19. I figured we could figure it out. The instructions in "How to Make Custom-Fit Bras & Lingerie" are so easy to understand and are a method that I never would have thought of. We've been able to make a basic toile and slope within a week and are now moving on to the first fitting and adjustment for the final pattern. I feel that this book would be great for those that are just learning to sew, and for those that have been sewing for a long time and are maybe looking for some new methods. Really a great book."

Vanessa Hart

"As a DDD size, I found the bust sling to be so incredible in fit, support, & comfort. I may never go back to a regular bra again."

Amazon Review

" I went through his process of creating a sling bra and came up with a well fitting muslin. Life got busy and I was never able to redo the process into the finished product. But that has not stopped me from wearing my sad little blue cotton muslin sling bra often. When choosing a bra in the morning it is that incredible well fitting and comfortable bra that I grab more often than not."


Bra Issues

The design of the Bust Sling Bra address the following issues:

  1. The need for underwires, read more.
  2. Absence of separation between the breasts, read more.
  3. A front opening even with a separating zipper, read more.
  4. Bra strap width, read more.
  5. Options for support of the breasts from the back, read more.
  6. Control of East/West drift at the rib cage and the full bust level, read more.
  7. Options for preventing elastic from rolling under the bust, read more.
  8. Lack of tension, resulting in a longer life for the bra, read more.
  9. Containment of soft tissue, "fluff," around the rib cage, read more.
  10. Inclusion of a bra cup or prosthetic device, read more.
  11. Attractive designs for large breasts, read more.


The conventional bra uses an underwire to hold the bra cup close to the body, particularly at the breast bone. Bra underwires can be problematic because:

  • Incorrect lengths poke the underarm area.
  • The left and right breasts can be different sizes.
  • Some women need an underwire that is flat on the bottom and no commercial underwire is shaped like this.
  • Underwires ultimately poke through the channeling with time.

The Bust Sling Bra eliminates the need for an underwire by using a suspension structure that follows the natural contours of the body.

Separation between Breasts

Some women have no separation between the breasts at the full bust level. This means that the underwires of a conventional bra cannot go high enough to provide adequate control of the breast tissue. The Bust Sling bra only requires the thickness of the fabric to fit between the breasts to provide appropriate support. Moreover, fabric between the breasts absorbs perspiration.

Front Opening

The largest front closure clasp for a conventional bra is 1-3/8", which is inadequate for preventing East/West drift. The Bust Sling Bra removes the tension around the rib cage, allowing for a variety of front closure devices including separating zippers. This is especially convenient for women who find it difficult to manipulate a bra's back closure.

Bra Strap Width

The largest readily available width for bra straps for conventional bras is 3/4". A narrow bra strap can pinch nerves and result in other serious health issues. The width of the strap for Bust Sling Bras can be up to the full width of the shoulder-even wider than that found on back packs. For women whose breasts are smaller or self supporting, the straps on a Bust Sling can be as narrow as 1/8".

The width of the strap for Bust Sling Bras can be up to the full width of the shoulder--even wider than that found on back packs. For women whose breasts are smaller or self supporting, the straps on a Bust Sling can be as small as 1/8".

Support from the Back

Given that the Bust Sling relies on suspension, the support from the back up to the shoulders is important. Like the width of the strap, this will vary with the needs of the individual. For this reason, I show variations for the back that include a halter style around the neck, an "X" back, a racer back, and a hybrid that uses the same kind of band around the rib cage as a conventional bra.

East/West Drift

Large breasts tend to spread to the sides. The Bust Sling uses two means for controlling this East/West drift. The position of the Bust Slings can be adjusted at the rib cage. But additional support can be added to the full bust level using a bridge between the two Bust Slings. This bridge can incorporate a zipper. If desired, the bridge can even be carried above the full bust level.

Rib Cage Elastic

With conventional bras, the elastic band under the bust can roll up and become uncomfortable. For the Bust Sling Bra, you can use elastic of any width, including the wide non-roll elastic used in waistbands. I have even made a dress for my model that uses no elastic at all around the rib cage. This can be an important consideration for women who have scar tissue from surgery

Life Expectancy of the Bra

Many women find a bra only lasts three or four months before the elastic looses it's tension and is unusable. The structure of the Bust Sling is such that it does not depend on tension. As mentioned above, it may even be possible to make a Bust Sling garment with no elastic. This means a Bust Sling Bra should have long life expectancy.

Support for Fluff

Soft tissue around the rib cage is know as "fluff." This is uncomfortable when pinched by a tight band around the rib cage. With the Bust Sling Bra, the support comes over the shoulders, minimizing the tension around the rib cage. In addition, by offering different styles for the back such as the racer back and the hybrid there is an inherent ability to support this fluff in a comfortable way.

Profile Enhancement

The Bust Sling can include a pocket for either one side or both allowing the inclusion of a bra cup for profile enhancement or a prosthetic device.

Styling Concerns

Conventional bras for large breasts are often ugly and institutional looking. Bust Sling Bras can be made with any type of fabric and any type of elastic. The lines can be changed to create different designs as long as the underlying structure is maintained. Furthermore the structure of the Bust Sling can be used to create Empire style tops, dresses, and gowns that do not require an additional undergarment.

The Bust Sling as a Nursing Bra

Among the first women to create and use a Bust Sling Nursing Bra was Kenna who wears a "DDD" cup in a conventional bra, was new to sewing, and yet found this an easy garment to make. With her permission, I have included her comments below.

Bust Sling vs. Conventional Bra

"As for nursing, the bra works very well. I have quite a bit of experience with conventional nursing bras. Usually the part of the bra that falls away for nursing is the part of the bra that supports the breast. Therefore, when you nurse, the bra drops the breast. I love the fact that the bust sling does not do that. The breast is supported through the nursing, and that feels better to me. I do have to hold my baby a little further out from my body due to the projection, but that has not been a problem."

Fungal Growth

"It's not unusual for women with ample busts to struggle with fungal growth on the skin underneath the breast. This is a real problem. Your design prevents skin-on-skin contact, which prevents sweating, which prevents that fungal growth. A+ for the help in that department."


"The other day I started experiencing pain from a clogged milk duct. Guess what! The fact that the Bust Sling Bra has no underwire and is very gentle on the breast tissue made it the perfect bra to wear while trying to prevent the pain from turning into full-blown mastitis. Another A+."

Cost and Durability

Kenna is new to sewing. She found this an easy bra to create.

"It's nice to know that even a beginner's experiences can be useful. I plan to recommend this bra design, and your class, to anyone who asks me about nursing bras. I find your design very refreshing. Bras have been a constant source of angst for me for many many years.

"Another little tidbit about your approach that I love is the cost factor. When I buy conventional bras, they easily cost me $60.00 per bra, if not more. Then they last for no more than a year, and often times less than that. If I launder them adequately to prevent fungal growth, they will last no more than 3 months. With your approach, I can make a bra out of material that can be laundered, and I can do it very economically.

"All these things have me very excited! I get good fit, adequate support, ease of care, better skin health, and a great nursing bra for a very reasonable price."

Copyright © 2023 by Donald H. McCunn