Shapes?! Lengths?! MM?! Style?! How do I actually choose my underwire??
Are you a home sewist? An indie designer? A new brand? How do you choose your wire? First things first, you might want to find out what shape you need. Doing a breast root trace will give you a clearer idea of your shape/client’s shape/fit model’s shape.
From the breast root trace, you can lay various underwires overtop to see if once sprung open (stretch the underarm part of the wire outwards) they match the shape of the trace. Wires are usually around 15mm in core sizes, upwards of 50mm in large cup sizes.
As for determining style of underwire, there are plunge wires, balcony wires, half cup/strapless wires…these all have a different wire profile suited for the bra that you will design. Shapes of wires are not interchangeable. Just because you want a shorter wire for your bra, does not mean that it may be the right shape. If you imagine an X-Y axis (a grid of sorts) the lowest point of the wire, we call it the balance point (BP), should be resting on X, and the centre front (CF) tip resting on Y. This shape then needs to be sympathetic to the shape of your cradle for a good and comfortable fit. You don't want to drastically 'rotate' the wire in order to fit it into your bra.
Wires come in a variety of lengths! Every size is different, every shape is different…but there is a theme to them. Wires grade up in size, just like our bra patterns. The ‘rules’ are different for each brand, and some ‘rules’ seem more common by region. I can only comment on what happens in the UK as that is where my training is from.
One thing that IS important to remember if you are building a brand for yourself - once you’ve chosen a ‘root shape’ for your wire, it’s probably a good idea to stick with it. Wires are designed as ‘families’ with shapes that are similar to each other, just different lengths and styles, like higher/lower centre fronts and underarms. As customers come back to purchase again from you, if you’ve switched to a wider or narrower underwire profile, they’re going to know, and your brand might not work for them anymore. Anyone that did try your brand, and the wires didn’t work for them, probably won’t be back to see what’s new.
In an earlier blog post I covered Core & Plus Size Grading, and just lightly touched on wire grading. In the UK, core size bras (usually A - D/DD cups) will grade their wires by 21mm. This means that each wire size is 21mm different from each other, so little bit longer and a little bit wider. I've included a photo in Underwires 102 of a graded nest of wires.
In what the UK calls plus size bras (DD+ cups) wires traditionally grade by 16mm. So not quite as much as core sizes, but from a 32F to a 38F, that wire is 48mm (4.8cm!) longer.
The above information is what is commonly found in the UK. Please note that the styles you buy, or the ‘rules’ in your region or company may use different or proprietary grading increments.
Lastly, when you’re selecting your underwires, it’s important to make sure that the wire is going to fit into your bra! You want to make sure that the wire fits, and that you have room for wire play, anywhere from 11 to 16mm is industry standard. This is room for the wire to move within the channeling. Too much or too little wire play may result in the wire popping out.
Looking for more information about underwires?
Educating women on the benefits of proper fitting bras is important to Kim. Designing lingerie that complements the fuller figure, and is comfortable, on-trend and beautifully constructed is her mission.
We are in charge of our bodies, and we make the decisions that are right for us, with no judgement. Kimtimates supports those who make their own choices about their own bodies. #yourbodyyourchoice #mybodymychoice