Patternmaking Bust Cups vs Bra Bust Cups (Part 1: Bodice Block Essentials)

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Video Transcript

00:00:00:09 – 00:00:23:02

Hi, this is Maria from In this video, I’ll be explaining the difference between pattern making bust cups and bra bust cups. Some people may end up with the same bust size for both making and bras, but they are actually measuring different things.

00:00:23:02 – 00:00:51:00

They are not the same measurement. A lot of people will not end up with the same bust cup for patternmaking as for their bra. Therefore, it’s important to understand that they’re different and check and use your patternmaking cup when drafting your Bodice Block. This is Part 1 in a series of videos on Bodice Block Essentials. These videos are shorter theory based videos compared to the ones I’ve put up so far, which have been longer, step-by-step instructions.

00:00:51:08 – 00:01:14:16

If you’re planning on drafting a bodice block to your custom measurements, I would recommend you watch these 6 videos before starting to draft your Bodice Block, so you have a good basis, a good understanding of what you are doing. Part 2 will cover ease, what ease is and how much is included in the Bodice Block instructions. This video is particularly for those people have sent me queries about the amount of ease I add in my instructions. In this video

00:01:14:16 – 00:01:36:22

I will show or prove if you wish, that the amount I add is pretty standard and the only reason it appears to be a whole lot more is that my system is based on the Upper Bust rather than the Bust. In Part 3, I will go into detail about the patternmaking bust cups. My system allows for drafting the bust-cup within the block-making instructions rather than first drafting the block, then doing a Large Bust Adjustment.

00:01:37:14 – 00:01:58:19

I will show that my system does produce the exact same result is doing an LBA, except that you achieve it within the block making process. Part 4 will put together what was covered in parts 1 to 3, to show why the Upper Bust is so important. Because the Upper Bust is very neglected and why it makes sense to draft the bodice block based on the Upper Bust rather than the Bust.

00:01:59:16 – 00:02:22:07

In Part 5, I want to just briefly show you the adjustments that I am making or will be making to my Bodice Block System to improve it further. What this means is, after doing this six videos, I will be remaking my Bodice Block instructions videos. There’s two of them; Bodice Block Front and Bodice Block Back. I have refined my system to get a better result for more people.

00:02:22:20 – 00:02:48:06

And so in Part 5, I’ll be explaining the changes only. I won’t be actually doing the step-by-step instructions. I’ll just be covering how my system will be improved and the videos will be coming shortly after that. In Part 6 of the series I will be covering Measuring for the Bodice Block, and instead of using the small vector graphics I used in my previous videos, I will be showing those measurements on the dressmakers dummy shown on this slide.

00:02:48:06 – 00:03:08:07

There will be. I’ll also be adding a couple of measurements to my system. All of the measurements will be shown on the moulage that she is wearing and that toile will have all the measurements marked on it. It will show the measurements much more clearly, and I’ll go into detail about how to take those measurements. So let’s get started for Part 1.

00:03:08:07 – 00:03:26:07

Bra Bust Cups are determined by the difference between your Under Bust and your Full Bust. It should be obvious that the under bust is a key measurement for the bra. The Under-Bust measurement is what determines your band size, and the band is what does the work of supporting the breasts. The straps actually don’t do any work in supporting the breasts.

00:03:26:16 – 00:03:49:15

The Under Bust is totally irrelevant for your bodice block. The Under-Bust measurement is not taken. It’s not needed to draft the bodice block. If you want to shape your garment to fit really well under the bust, you do that with the waist dart and/or with stylelines such as the Empire style line, which will take the fabric right underneath your breast and then you can get a close fit from there down to your waist.

00:03:50:04 – 00:04:21:12

So to repeat, for drafting the bodice block, the under bust measurement is irrelevant. For patternmaking, the Bust Cup is based on the difference between your Upper Bust and your Full Bust. So for the rest of the video, I will show you the how and why of the upper bust and full bust measurement working together to shape the bust. As it pertains to drafting for the bodice. On the left is Didi, my dress makers dummy and on the right is a fiberglass cast of my body taken a few years ago.

00:04:21:12 – 00:04:43:18

So my measurements may be a bit different nowadays, but for the purposes this exercise, that doesn’t matter. Both Didi and I have the same Bust measurement. We both have very different Under Bust measurements, which is not relevant to drafting the bodice block. But we also have very different Upper Bust measurements. Didi has half inch difference between her Upper-Bust and Bust.

00:04:44:08 – 00:05:07:17

I have three and 3/8 inch difference. Now, an important note here someone new to sewing or patternmaking that wants to buy a dressmaker’s dummy like this, might buy according to the bust size. If they did and they had my type of body, my measurements, then they’d be in trouble. If they made a close fitting garment from a woven fabric, they wouldn’t be able to zip it up on the form.

00:05:07:23 – 00:05:32:17

If they made it to fit the form, it would gape in the upper bust and armhole area. If the body form is not adjustable, you need to choose the form according to your upper bust measurement. But most places that sell these forms don’t include the upper bust measurement in the specifications. So as far as Didi and I go – for pattern making bust cups, she is an A cup, or less than an A cup and I am a C Cup.

00:05:33:18 – 00:05:56:07

So for drafting the bodice block, you use the difference between your upper bust and bust to determine what your patternmaking cup size is. 1 inch differences is an A cup. 2 inches is B cup. 3 inches the C cup, etc. If you have only half an inch difference like Didi or if you are between sizes, so for example you have 3 and a 1/2 inch difference,

00:05:56:07 – 00:06:16:08

you are between the C and the D cup. Don’t worry about that now. The focus for this video is understanding how pattern making bust cups work. In my Block Making Instructions, I will show how to make adjustments for those differences. Since Didi has only half inch difference between her bust and upper bust, she has less than an A cup.

00:06:16:17 – 00:06:36:10

In Didi’s case, her bra size and her pattern making cup size are the same or pretty close. If I put her measurements into a bra cup formula thingy, it says that she’s an A bra cup. Since I have more than 3 inches between my upper bust and bust, I’m actually a bit bigger than a C cup for making purposes. In bras

00:06:36:10 – 00:07:03:09

I take 14DD or 14E, depending on the make and the style of the bra. And of course this is Australian sizing, so it might be slightly different to European or American sizing. Now I have already said that the under-bust is irrelevant. Why am I still talking about bra cup sizes? I just want to compare and show you that, for example, Didi’s bra and patternmaking was very similar, whereas for me it’s quite different.

00:07:03:09 – 00:07:30:12

So I’m stressing the point that you don’t go by your bra cup size, that you need to go by your pattern making cup sides. You need to take your measurement at your upper bust and compare it to your bust to get the relevant measurement for drafting a Bodice Block. Now just a little bit more on bras before I continue with pattern making cups, I went to a bra website and put in my under bust and bust measurements and it actually says that I apparently should take a C cup.

00:07:30:24 – 00:07:50:16

So if I bought a bra through them online according to the sizing specifications, I would get a C and they would say it would fit. Now actually never looked at this before as in I’ve never plugged my measurements into a bra calculator. So I was surprised at this. But what I’m surprised at is the website doesn’t tell you that for some people their formula doesn’t work.

00:07:51:10 – 00:08:11:13

Now for those who may wonder how that sizing doesn’t work for everybody, there is a website called Foundations Revealed. I don’t have anything to do with them. I’m not plugging them for any reason other than they’ve got some useful information. It’s mainly corsetry, but they have a few free articles on bras by designer and costume cutter Luca Costigliono.

00:08:11:13 – 00:08:34:13

Now he’s apparently very well known. He does a lot for theater productions and films are in Europe. As I said, his specialty is corsetry, but he’s also very knowledgeable on bras. Now, in his words, it’s written here on the screen a woman who measures 29 and a half inches around her rib cage and 35 and a half inches around her over bust, but has a narrow back and full breasts.

00:08:34:24 – 00:08:54:22

So that would be, for example, me … and a woman who measures 29 and a half inches around her rib cage and 35 and a half inches around her over bust. But she has a muscular, wide back and small breasts. Using the traditional measuring method both of these women would be offered the same bra size, but they have significantly different body shapes.

00:08:55:11 – 00:09:15:06

So those bra calculators only work for a certain body shape. Doesn’t work for my body shape. And I’ll show you that a little bit more in a in a couple of slides. But I just want to say for the moment that I am learning to draft my own bras. So eventually, sometime down the track, I will write a tutorial on that.

00:09:15:23 – 00:09:43:11

Just to continue on with the example that Luca Castiglione gave that women with the same measurements … can have a very different body shape. I’ll just compare Didi and mine. Now we have very different upper bust and under bust, but if we just compare our bust, you can still learn a lot from that. If you split our bust into arcs, as in from side seam two side seam you’ll see that I have a very narrow back and a full bust, whereas Didi has a wide back and smaller front.

00:09:44:01 – 00:10:10:12

So you can imagine that the bust part of the bra, if it is designed to fit Didi’s back arc and front arc, it wouldn’t fit me. If it was designed for my ratio proportion of back and front, it wouldn’t fit so well on Didi. So back to making, Bust cups for patternmaking, the bust cups are based on the difference between the upper bust and full bust.

00:10:11:01 – 00:10:34:04

And using that difference you determine your making cup size. Now, before I go on to show you how bust cups work for patternmaking, I need to make two notes. The inch grid is just a background graphic. It’s not necessarily going to match up with the measurements that I’m using in the moulage. The second note is what Didi is wearing and the shapes I’m showing you here are ‘moulages’.

00:10:34:09 – 00:10:57:10

There is no ease in it. Now that means it’s made to the exact body measurements, and I’ve done this for the purpose of the explanation. You wouldn’t use a moulage to make garments to wear because you wouldn’t be able to move in them. Okay. So now to understand how patternmaking both cups work. If you look at the moulage on the left, I’ve made it a rectangle from the upper bust down.

00:10:57:12 – 00:11:29:06

So the width of the whole shape on the left is the upper bust measurement. If I made a toile to that rectangular shape and put it on Didi, it would obviously not fit because her bust is bigger than her upper bust. So in the photo in the middle, the green line that I am pointing to with a blue knitting needle is what would be the side seam if I put that rectangular shape on Didi. In order for the fabric to cover the bust as well, the side seam needs to go out on an angle so that the fabric can meet with the back at the side seam.

00:11:30:02 – 00:11:48:23

So the green wedge shape on the right is basically the bust cup that’s needed for Didi. So just to be sure that you understand these markings, the pink line is the upper bust line. The blue line is the bus line. The green line is the line squared down from the upper bust and the purple line is the side seam.

00:11:49:10 – 00:12:11:15

And so the bus cup is the piece of fabric that allows the fabric to return to the side seam of the body once it’s covered the difference between the bust and the upper bust. So I want to show you what happens if you make that wedge smaller than it needs to be. I’ve left the front waist unseen here, so there’s plenty of ease in the waist.

00:12:11:21 – 00:12:31:15

However, if I try to use that waist ease to reduce the bust cup ‘wedge’ … so I pull that green line to the side seam. I get pulling up to the bust point. Those stress lines show that the bus cup isn’t big enough. So here I’m not pulling up the green line, which is that rectangular line here. I’m trying to get the dashed red line to the side.

00:12:31:15 – 00:12:55:05

Same again. I still get that pulling. So there is a minimum amount which is needed to return the fabric to the side seam without pulling. And that minimum amount relates to the necessary bust cup. This is the minimum amount I need for Didi and if I try to reduce it at all, I start getting those stress strain lines. I’ve sewn up the waist darts

00:12:55:11 – 00:13:19:16

and you can see now that there is enough fabric to return to the side seam and there is no pulling and there is no gaping either. So this is the amount that Didi needs for her bust cup. Now, if I use the same bus cup amount that I used for Didi for me, and that’s shown by the green shading, then it’s not enough to cover my bust and return the fabric to my side seam.

00:13:20:00 – 00:13:42:24

Now the calico that’s on my body cast is made to Didi’s measurements. And as you can see, that wedge is nowhere near enough for me. So when I add the extra amount that I need because I have a bigger bust cup, the fabric can now be returned to my side, to my side seam. Well, actually, what would be my side seam if I actually had a back to attach to the front.

00:13:42:24 – 00:14:03:00

But you get my point. Now if you have a big bust and a small waist, you can end up with a very large waist part. But this is not a problem. You don’t have to use a 1-Dart block. You would usually use a 2-Dart block and in the process of making your pattern, you could manipulate that dart any way you want to create styles that suit you and distribute that dart elsewhere.

00:14:03:16 – 00:14:30:11

I am using the 1-Dart block because it’s easier to explain and easy to see how the bust cup works with it compared to the 2-Dart block. So here I have three blocks superimposed on each other. They have the same upper bust measurement, but they’ve got a B cup, a C cup and a D cup. As the bust gets bigger, the angle from the upper bust to the bust gets bigger and continues down to the waist…

00:14:30:11 – 00:14:57:05

a that larger angle. I have here superimposed ,,, Didi’s moulage and my moulage. So you can compare the shape. The one and only thing we have in common is the bust width. I’m smaller in the upper bust armhole and because I’m smaller in the upper bust, the angle of the side seam needs to be greater. As you seen in the slides leading up to this one. Now obviously they are ‘moulages’..

00:14:57:05 – 00:15:20:16

..but if we added some ease and I tried on Didi’s toile, I would have two problems. Firstly, I will have those stress lines pulling from the bust towards the side seam. Secondly, I’ll have a ‘loop’ in the armhole, which is not shown in the image. Now that loop is not a matter of just too much ease because I could draft a dress with a lot of ease and that doesn’t have that loop.

00:15:21:00 – 00:15:40:23

The loop is due to the angle of the side seam from the Upper Bust to the Bust being insufficient. It traps that bit of fabric there. So the loop that you get in the armhole when you have a large bust is about the bust cup being too small. Now, this is for anyone who may be wondering about the amount I used for the Cup in Didi’s moulage.

00:15:41:11 – 00:16:01:20

Someone may have looked at my instructions and may be thinking the angle of that side. Same line on Didi’s new large looks a hell of a lot more than 5/8 of an inch out from the upper bust rectangle as shown in your directions, in your instructions. Now that is because this is a ‘Moulage Without Ease’, not a ‘Block With Ease’.

00:16:02:01 – 00:16:38:04

And if you want detail on that, I’ll be covering it in detail in the upcoming videos. I just want to repeat that: The amounts that I give in the instructions for drafting the bodice block work only if you use the amount of ease I specify in the instructions. If you decide that you’re just going to add 2 inches ease instead of the 5 inches that I say if you decide to make a moulage and take all the easeout, then using those amounts that I have given – the 5/8 of an inch out for the A cup, and 1 and 1/4 inches for the B cup, they will not work. Those bust cup amounts in my instructions work only

00:16:38:09 – 00:17:00:24

if you use the ease that I specify. So to summarize, Patternmaking Bust Cups are determined by the difference between your Upper Bust and your Bust. 1-inch differences for an ‘A’ cup, 2-inches difference is a ‘B’ cup, 3-inches a ‘C’ cup , 4-inches is a ‘D’ cup, 5-inches a ‘DD’ cup, etc. Here you can see A, B, C cup and D cup superimposed.

00:17:01:08 – 00:17:20:14

These are all drafted for the same upper bust measurement. Using my system, you can draft a block that includes your bust cup rather than, as in most other systems, draft a B cup, then afterwards do a Large Bust Adjustment. Within my system I also start drafting the 1-Dartblock, then make the necessary steps to change that into a 2-Dart block.

00:17:20:22 – 00:17:40:23

So at the end you have a 2-Dart Block with your bust cup, so it will fit you in the Upper Bust and the Bust. Remembering that you need to add the ease that I have specified OR those amounts I have given will not work out. In the next video I will cover ease. I have already created all the slides so there’s only the audio to do.

00:17:41:08 – 00:18:00:08

I do have a really sore throat at the moment, so I might not get that up until next week, but I will be doing one of these videos a week, generally putting it up on YouTube on a Sunday night. After these six videos, I will be remaking tthe Bodice Block Instructions as I have refined my system. So next week the video will be one Ease.

00:18:00:14 – 00:18:02:20

This is Maria from Dress Pattern Making Chow.


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