Patternmaking Tips for Bras




some patternmaking & sewing suggestions to help guide you through your first underwire experience

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Step 1: Breast Basics

before getting started, it is useful to review some basic breast physiology. you may have your own method for brushing up on this, but to aid in your research at home, here are one or two facts:
+each breast is 90% water, can weigh 200/800 gms, sits on the chest wall between the 2nd and 6th rib,

+statistically, left breasts are often slightly larger than right ones, (up to 2 cup sizes!) though i encourage anyone to challenge this by submitting your own research on the topic.

+breasts have no internal support structure and rely almost totally on skin tension for their shape. this is where the bra comes in.

Step 2: Making Your Pattern

you can do this however you like- above are some basic pattern shapes for a simple balcony bra (ive graded it for sizes 34 and 36B)

as with many things, the best way to learn is by taking a good bra apart. (its also possible just to reproduce the measurements of your current favorite bra . be exact; its deceptively easy shave off a few millimeters here and there and come out with a very odd looking bosom.)

Step 3: The Underband

here is a picture of an ineffective underband.
the underband of your bra is critical for fit, support and comfort; it cantilevers the weight of the breast into the lower back, making a secure platform for the weight of the breast.

(keep in mind the length of the bra underband is smaller than the natural rib cage measurement of the wearer-- a common underband length for a 34 band bra is 24.5". The formula fit for a 34 band size has a 29/30 rib cage measurement-- therefore the underband has to stretch from 24.5"-29" when worn.

Step 4: Underwire

your underwire should not sit straight in the x-y axis of the cradle, but should be offset by 5mm; when it is on it shifts back into place. basic wire length is 196mm, and when making your pattern, trace around the wire and extend the shape by 8mm at each end.

Step 5: Center Front Tape

the key to getting that angle and uplift, this tiny piece of fabric between the cups is what determines how much cleavage is produced. it took a team of designers 6 months to work out the magic of the wonderbra (still the most popular bra style in the world), and the secret is in the angle at which the centerfront tape is cut. will i tell you the angles? go measure for yourself!

Step 6: Fabric & Other Components

stretch fabric is preferable, obviously. even a silk that has 5% lycra works nicely. in general, you want the stretch in the cups to go horizontally so that the cup does not move up or down, or can be tilted a few degrees.

it can be tricky to find lycra lace in the color you like. dying fabric is, in my opinion, super fun. use hot water dye for anything with synthetics in it. i am particularly fond of dying lace in shades of cherry.

(i recommend the marche st pierre in the 18th arrondissement for the best european fabrics. its conveniently close to the moulin rouge, too, if you want additional inspiration. living next to that revered establishment resulted in a number of feathered bras and thongs.
or if you're in london, broadwick silks has a really spectacular taste and selection, and its just down the street from agent provocateur!)

in any case, you'll need your fabric, straps, clasp, additional elastic, and anything else you choose to add.

Step 7: Cutting & Sewing

trace your pattern onto selected fabric, and cut delicately. (alternatively, a laser cutter might work brilliantly, especially for slippery silks that you have to cut on the bias)

if using rare or expensive fabric, it is worth your time to make a toile (using a cheap but similar material) to work with the fit, before cutting and sewing the final.

once you're done, you can wear your new bra in a whole panoply of contexts. my favorite is lounging on a lazy and hot summer afternoon with a close friend, sharing secrets, sipping tea or a vodka tonic, and trying on underwear!

Step 8:



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    47 Discussions

    Kink Jarfold

    1 year ago on Step 8

    A fan of bras for al long as I can remember --nicely documented, my dear.


    8 years ago on Introduction

    Here is the page for the free bra pattern! It is on the Burda site...and you might have to read in the comments to figure out which pattern size you will need!

    I wear a 34GG and I had to get pattern #5. I will have to alter it a bit down from the 36....but is pretty darn close!

    I am excited to give it a try soon!

    I will probably start some personal sewing after my daughter gets back to school from holiday.

    Hope you all post great pics!

    Thursday Next

    8 years ago on Step 2

    go to amazon/books/ hobbies and crafts/sewing. and type in underwear. there are a lot of them. I tried to post a link but it didn't show up as a link.


    8 years ago on Step 3

    "here is a picture of an ineffective underband." LOL!! :D


    8 years ago on Step 8

    Looks like good information but I wish I could find a set of patterns that had various sizes. Reverse engineering every piece of clothing I want to make takes a lot of time.


    13 years ago

    Great information - thank you for sharing ! Now lets see if I can make a 36G.

    6 replies

    Reply 9 years ago on Introduction

    good morning fineline; If you goto: and check out the "free patterns" member fiefje has posted bra patterns and basic directions. There are, at last count, three styles, and I lost count of how many individual sizes. But, G was one of them. You do have to register to download patterns. It is still free, and not full of spam. Cordially, Nehmah


    Reply 9 years ago on Introduction

    hi I couldnt seem to find the pattern could you post a link? thanks Stephanie


    Reply 9 years ago on Introduction

    Hi Stephanie, I'll try but am lousy at linkage. There are two sites to cover. About both, you must be registered to download any pattern. It's free and the spam was minimal. Also, at the "old" site, the Sept.closing date is for real. If you want any of the free patterns best to download now. Many of these never made it to the new beta site. Here they are: and for the others, change number from 1 to 6. Now, let's see if I got it right. Cordially, Nehmah


    Reply 9 years ago on Introduction

    The second link to the new site may not work, due to registration restrictions. If you goto: you get there, (on my username(?) oh well, as long as you get there. I hope that you find the site(s) they are useful. Cordially, Nehmah


    Reply 9 years ago on Introduction

    NOTE: The "" will be unavailable after September 30, 2009. If you want to download any of these patterns, get them now. They may not all be transferred over to the beta site. There are some super patterns on there that are still free. Cordially, Nehmah


    10 years ago on Step 8

    Thank you so much for the information. I have had many years of unfit, overpriced bras...and now I will make me some.


    12 years ago on Step 1

    Actually the breasts do not rely on skin for support. Breasts are supported by Cooper's Ligaments. Ligaments stretch over time but do not rebound. Hence this will eventually lead to sagging if the breasts are not supported by some other means (i.e. a bra, corset, etc.)

    2 replies

    Reply 10 years ago on Step 1

    I remembered reading from many places though, that bras actually contribute to sagging...


    Reply 11 years ago on Step 1

    I'll also note It doesn't really matter if the breasts are supported. The ligaments weaken and stretch naturally, not because the breasts were unsupported, so they'll sag either way. Wearing a braw is more about keeping them shapely now, not so much preventing the sag later.