P2031465 The Construction of Bras

I’m going depart from my usual routine of writing about various sewing and pattern making topics and focus on one topic for the next two weeks. Recently, I’ve seen and read a lot, both in magazines and on blogs, about bras, lingerie, trousseaus, foundations or whatever those pieces worn underneath clothing are called. I was never interested in sewing a bra or a panty (I hate those words, do you?) until I realized that a good fitting outfit starts with good fitting lingerie. I spent 3 months perfecting the fit of my sloper yet never thought to perfect to the fit of what I wore underneath. Yes, I wore the same bra during each muslin, which is super important, but who knew if that bra fit me correctly. I never thought to check.

Lingerie is also an interesting and fun category. Interesting in that lingerie is sewn quite differently than “normal” clothing and fun because lingerie can be sewn in a day, not weeks or months. Also, there’s no rolling up the rugs and bending over on floor to cut pattern pieces. Because the pattern requires so little fabric, the pieces can be cut on even the smallest table, which is a huge plus.

So for the next two weeks, I will be writing about all things bras – the construction of bras and sports bras (I’ve been meaning to do a follow-up post on sports bras since I wrote about the construction of “normal” bras), how and what constitutes a good fitting bra, how the shape of bras have changed over the decades (this is really cool), as well as my favorite bras (for eye candy). I’ll start today with the construction of “normal” bras. I admit that this is a repost from a couple of months ago but since posting it, I have done more research on the topic and have added a few tidbits here and there. So without further adieu, let me get started…

P20314831 The Construction of Bras

1. Bras can be sewn with many types of fabrics. Tricot (a warp knit), lace (stretch and non stretch), satin (stretch and non stretch), cotton (knit and woven), and Lycra are the most popular choices. If you are using a bra pattern you haven’t sewn before and are unsure if the fit is correct, I suggest to use a stretchy fabric. Because of the give in the fabric, the bra will more likely fit you, regardless if the fit is correct. If you are using a bra pattern you have used before and I’m assuming you have altered if the fit was incorrect, it is okay to use a woven fabric. Because a bra is so close fitting, even an 1/8″ off throws off the fit. This is why I’m against using woven for lingerie unless you know the fit is perfect.

2. Bras are sewn just as “normal” clothing except that the seams holding them together are zigzag stitches (or coverstitches in some cases), not straight stitches. This is because as we move about our day, we move, twist, and stretch. The bras we wear need to be able to withstand this movement. Straight stitches have no stretch and would pop under such stress. But zigzag stitches have give and stretch to them and, therefore, are the reason the seams are sewn with this stitch.

Also, the top and bottom edges of a bra usually (about 95% of the time) have elastic sewn to it. The elastic is cut shorter and stretched slightly during sewing to provide give. Its purpose is twofold. Its first purpose is the same as the zigzag stitch – to help the fabric stretch as we move. Its second purpose is to help the fabric recover from the stretching it undergoes.

elastic The Construction of Bras

3. There are four main components to a bra- band, cup, strap, and closure.

The Band. The band may be single ply (layer) or lined. There are different types of bands depending on the amount of support desired. A full band wraps around the entire circumference of the body, including between the bra cups at center front, and provides the most support. A partial band is attached to the sides of bra cups (there is no band between cups at center front; instead, a hook or center front piece connects the cups) and provides less support than a full band.

I also recently learned, thanks to Novita, that bands can be cut on the bias to provide more give. Neat little trick, right?

The Cups. The cups can also be single ply (layer) or lined. Although cups made from a single piece provide a good fit, cups that are made up of 2 or 3 vertical or horizontal pieces provide the best fit. The benefit of having more pieces is that the cup will contour to the shape of the breast. Although two woman may wear the same cup size, the shape of their breast are different. Having 2 or 3 pieces will help the cups fit the the different shapes of the two women’s breast (it’s the same principle as using princess seams).

Just a few tips when sewing cups…

Sew cups first, then attach band, elastic, straps, and closure. It’s the best order of operations.

Also when sewing cups, sew with lower cup against breast plate.

There are many ways to press open cup seam allowances. The first way is to press open seam allowance and top stitch each seam allowance on either side of the seam. The second way is to press open seam allowances and then press seam allowances either up or down and top stitch on one side of seam. The third way, and my favorite way, is to press open seam allowances and then top apply a straight piece of lace or organza. All methods of pressing are best done with a tailor’s ham.

straps The Construction of Bras

The Straps. The straps can be made of elastic or self.

If you have made your own bra pattern, it is okay to have self straps. Self straps do not give like elastic straps and therefore should only be used it the fit is correct (you don’t need the stretch if the pattern fits correctly). If you’re using a pre-made bra pattern and don’t know if the fit is correct, it is best to use elastic straps that will provide give in case the bra does’t fit 100% correctly.

The  construction of straps used to confused me. They wrap this way, then wrap that way, then loop through this and then loop through that. Confusing right? But once I broke it down (as I did in sketch), it was actually quite simple to understand.

The Closure. The closure of a bra can either be at the front or the back. If the closure is at the back, it is usually has 3 hook and eye closures for to accommodate different widths (see second image).

4. Lastly, and this is a little tidbit but an important one, all major stress points are tacked with a zigzag stitch. Again, this has to do with withstanding our movement. It’s simply a reinforcement to prevent the straps from ripping.