Hello there! Welcome to my first “real” post as an editor of the Curvy Sewing Collective. I’ll be kicking things off with a series of posts on a topic that’s close to my heart: Dealing with large Full Bust Adjustments (FBAs) and the Big Honkin’ Darts that can result when you’re performing a large FBA (greater than 1.5-2″) on your pattern pieces.
Many commercial sewing patterns are drafted for women with a B-cup pattern size, meaning women who have a 2″ difference between their high bust measurements and their full bust measurements. If your high bust and full bust differ by more than 2″, you might need to choose a smaller pattern size than indicated on the pattern size chart and perform an FBA to get a good fit with your pattern.
If you’re not familiar with FBAs but suspect that you might need one, the CSC already has several posts discussing this alteration, which I recommend reading before continuing with my post:
The CSC has more posts related to FBAs, but I’m listing these two because they’ll get you up to speed on one of the most common FBAs: an FBA on a darted bodice, which is what I’ll be discussing in this post.
Differences between a small FBA vs. a large FBA
Most online tutorials and fitting books that describe how to perform a FBA typically deal with only adding a small-to-moderate amount of ease at the bust. The most common scenario that I’ve seen is a 1″ FBA. But what if your pattern cup size is much larger and you need to do, say, a 3″ or even a 4″ FBA?
Adjusted pattern pieces can look significantly different when you’re doing a 1″ FBA vs. a 3″ FBA, and if you’re doing a 3″ FBA, there’s a good chance that you might need to perform some additional or alternative pattern alteration steps to get a fit that you’re happy with for your garment. My goal for this post is show you the differences in appearance between a smaller FBA and a large FBA (hint from the post title: the dart gets really big) and discuss your options for dealing with those differences.
Let’s start by looking at a small slash-and-spread FBA, like you’d typically see in most fitting references. Note that in my images, I’ve drawn in seam allowance lines and that we’ll be working with quarter-scale patterns in this post.
Start by drawing in your typical FBA lines:
Slash and spread your pattern pieces to perform an FBA that would be approximately 1″ on a full-scale pattern. These shapes should look familiar if you’ve read through other slash-and-spread style FBA tutorials:
But what happens to those pattern pieces if you triple the size of the FBA? Let’s swing the side piece of our pattern out to mimic a 3″ FBA:
Note these key differences:
- Armscye: The armscye angle is much sharper in the larger FBA. A little bit of a sharper angle is a good thing in that it can help minimize that fold of fabric above the bust that larger busted women sometimes get, but this example shows a pretty extreme angle.
- Bust dart: Look at the size of that dart! In fact, you could call this a Big Honkin’ Dart.
Large FBA = Large Dart
Let’s talk about that Big Honkin’ Dart a bit. The Big Honkin’ Dart might solve the issue of adding more ease to the bust, but it also creates a few fitting problems of its own. If you’ve ever sewn a garment or a muslin with a Big Honkin’ Dart, you’ve probably personally encountered the following issues:
- Very large darts are very difficult to sew cleanly. I’ve read that if you have any more than 2.5″-3″ between the legs of your dart (depending on what you’re reading), you’ll exceed the limit of being able to sew the dart cleanly.Think about it this way: the larger the distance between the dart legs, the more fabric you have to account for when you’re trying to sew to a gradual point at the dart’s tip. If you’re backing the tip of the dart off from your bust apex, as many large busted women need to do, you’ll have even a shorter distance to sew to a clean point at the dart tip.
- Once sewn, you now have a large flap of fabric on either side of each breast, adding bulk where you probably don’t want any additional bulk.
Here’s an example of a Big Honkin’ Dart in a muslin that I sewed a few years ago to illustrate some of these points. In particular, look at that big, floppy, unattractive fold of fabric hanging off the side of my bust.
(Yes, this blouse muslin had numerous fit issues beyond the Big Honkin’ Dart.)
Okay, so now that we know that our Big Honkin’ Dart is causing us a few issues. What can we do to fix those issues? You have several options for dealing with a Big Honkin’ Dart, depending on where you’re at with your sewing project and how comfortable you are with pattern alterations. The following table summarizes each of these options:
| Solution | When to use? | Pros | Cons | Comments |
|---|---|---|---|---|
| Trim or serge off dart excess. | You’re working on your real (not muslin) garment. | Gets rid of dart floppiness. | Doesn’t fix other fit issues. | Use this fix only when it’s too late to go back and make changes to the paper pattern. |
| “Cheater” FBA by grading to a larger size at the armscye. | You’re in a hurry or aren’t comfortable with more complex pattern alterations. | Decreases the size of the FBA you need or eliminates the FBA altogether. | Doesn’t fix other fit issues; may lead to a too-large armhole for your body. Doesn’t add length over the bust. | Tends to work better for knits than wovens. |
| Y-Dart FBA | At the pattern alterations stage. | Decreases bust dart size and fixes other FBA-related fit issues. | Depending on your build, might add too much fabric to your upper chest area. | Some sewists swear by this alteration, but it doesn’t produce the same results for everyone. |
| Rotate all or part of the bust dart to another location on the bodice. | At the pattern alterations stage. | Decreases bust dart size or eliminates bust dart. Fixes other FBA-related fit issues. | Not every bodice pattern has an intuitive location to add/rotate a dart. | My favorite way to deal with a Big Honkin Dart, as long as there’s a good spot for rotation. |
In upcoming posts, I’ll go into more detail about how to do both the Y-Dart FBA alteration and how to rotate all or part of a bust dart to another location. In my opinion, these pattern alterations are the best way to tackle the Big Honkin’ Dart issue, if you’re still at the muslin or pattern alteration stage and are willing to slice up your pattern a bit.
If you’ve been struggling with trying to perform and fit large FBAs, I hope that this post provided a decent introduction to one of the big issues that you might encounter.
Hi Michelle
i am really glad to find your precius pages and thank u for share your knowledge – it help me alot when excute my task as a garment tech in factory and always deal with US customer which is has differnt body then Asian women
your self explanatory is very clear to understand and follow –
look forward for other curvy alteration on pants as well
again thanks for sharing 🙂
I have often wondered how the dress designers for big busted stars do an FBA. I found this picture of Dolly Parton the plaid helps to see the dart. It looks to me to be almost 90 degrees. I suspect it is eased like a sleeve cap at the yoke.http://userserve-ak.last.fm/serve/_/7658929/Dolly+Parton.jpg
Wow! Great fit! I’m practicing this technique with a Burdastyle top. Let’s see if I look like beautiful Dolly!
With all of the tips and tricks on here I finally have a pattern I can sew and like the way I look. I have an uber large bust and trying to get my darts to line up was impossible or at least for me. So I split the dart in two and moved it to the shoulder seam and the hem line. Then I got really brave and made a princess seam out of the two darts. Love it!!! My other option was I moved the dart to the shoulder seam and turned it into gathering instead of a dart. Love it too!! Now I have two options from one pattern and learned how to move darts. I love Curvey Sewing Collective and I am so glad I finally found it.
Oh my gosh, Yes! Can’t wait for your next post. Those drag lines on your sample muslin, above and below the ‘big honkin dart’, are EXACTLY what I have on a muslin I’ve been working on. Very interested to see more about your solution.
I got rid of the lines above the bust by raising the armscye a touch (and modifying the sleeve cap accordingly). You might need to do this if you’re petite in the torso (I’m 5’2″) or if the pattern’s armscye is just drafted too low for you.
The ones below the bust? Well, that’s another post. I’ve stopped trying to get rid of those on a single-dart bodice like this one–I think that on certain figure types, you can decrease them, but can’t necessarily get rid of them altogether, unless you go to princess seams or a curved French dart. But I’d be happy to be proven wrong on that.
Ah, that makes sense. I’m 5’4″. Armscyes are almost always too low on me, both in sewing and RTW.
And the shirt I’m making is a single-dart bodice (Sewaholic Granville). I’m pretty sure that if I went ahead and did a normal FBA with a waist dart the problem would go away, and I’ll probably do a version like that. But I was planning on multiple versions, and some of the fabric I want to use I think would look better with a single dart. A post about how to minimize those drag lines would be awesome. I think if I could just lessen them I could live with it.
What a wonderfully full bodied post!!!…just skimmed it and already know it is going ot be very helpful. …. now to peruse it over a brew.
THANK YOU Curvistas xx
I have an opposite problem – I am a large woman with a small bust. I wear a 48 B-C. Will you be showing how to downsize a pattern? Usually, I make two different pattern sizes and follow the larger size pattern to work the waist into the smaller bodice part.
Hi Amelia, I don’t have plans at this time to cover Small Bust Adjustments (SBAs), which might be what you need some of the time. However, many patterns are drafted for B/C cups, so you probably wouldn’t even need an SBA with those. If your bust pattern size is simply smaller than your waist pattern size, you’d probably just want to grade/blend sizes between the two. If you do want to learn a bit more about SBAs, I suggest checking out Trena’s blog, The Slapdash Sewist–she’s posted quite a bit about them over the years.
Thank you for your prompt response. I will check out The Slapdash Sewist.
Another option would be to add multiple darts that add up to the size of the one dart.
Yup–that’s what I’ll talk about when I get into dart rotation.
Michelle! So happy to see you here and can’t wait to read more about the darts!
Once again Michelle, you are my sewing and blogging hero! I always thought that the y dart or the shoulder rotation wasn’t working because of my lack of sufficient sewing skills. But with my tiny and sloping shoulders, there just isn’t room if it is coming from the top of the shoulder. Patterns like the Muse Gillian where the gathers are below the shoulder work better. I was so pleased to have mastered what I thought were the basics of FBAs (actually more than that given how much experimentation I’ve done over the past three years), and then seemed to have discovered a whole new world of shoulder and armscye fit challenges. It is a relief to discover they are related. Well done CSC team for inviting you on board!
Yes! I have found that shoulder yokes/gathers are very good friends of mine, when it comes to large FBAs.
I too look forward to your next post regarding large FBAs. I usually have to make FBA’s 2 inches or more.
Oh, AT LAST! Thank you for showing the truth of what happens to your pattern when your FBA needs a BHD!! Those weird armscye mutations are the bane of my life, I can’t wait to see your next post, as I’ve tried the double-dart approach but like Jenny it’s not worked out well.
Great series for the CSC!
A bit of 2 cents-edness 🙂 here … the dart “flap” you show in your photo … you *can* just trim those things, you know. And you don’t even have to finish the edges since it’s bias and won’t fray. Also, when you’ve got a BHD, try “drafting” and pressing the dart UP. First, it’s more flattering on a big bosom, and second, it’s takes less fabric. Dart extensions on BHDs are fabric hogs.
Right, and I did mention that as an option (trimming off the dart excess). For me, I feel like that works okay after the fact, but I’ve generally gotten better results from rotating part of the dart elsewhere.
That’s a great tip about drafting the FBA so that the dart is pressed up. I also know that in theory, it’s supposed to make things look “perkier”, although I haven’t noticed much difference on myself.
Ahh, you did mention it. Sorry about that – the table got scrambled when reading on my phone.
I think the “perkiness” factor is just a subtle thing. Since the dart is pressed up, the “shadow” of the uptake sits higher so your mind is slightly fooled that the breast is sitting higher. I dunno. We sew so our minds aren’t fooled. Heheh
I think the best part of upward facing dart (a new yoga position?) is just saving on fabric. It’s amazing how much LESS fabric one needs if one uses upward darts and reduces seam allowances to 3/8 from 5/8. This is a real consideration for those of us sewing in the higher size numbers especially when buying fabric online from places that only do 1-yard increments. I’m looking at you Gorgeous Fabrics. 🙂
I hated princess seams in my younger years. I thought they looked old ladyish. Now that I am older and larger in the bust, they have become my alternative to the ‘big honking dart’.
I don’t see a lot of armhole princess seams in RTW, but I’ve seen a lot more armscye princesses in recent years.
Armscye princess seams can still be slightly problematic with BHD’s because the curve on the side panel is so extreme. One way to fix that is to do shoulder princess seams
Looking forward to this, too, I usually need to add 3-4 inches, which I have always found it easier in an armhole princess than a darted bodice.
It’s much easier to make a large FBA look nice with princess seams than with a darted bodice. I’ve generally found that i prefer shoulder princess seams over armscye princess seams because the curve isn’t as sharp on a shoulder princess seam. You can also convert a darted bodice to princess seams, too.
BUT sometimes you just want to make something with a darted bodice–maybe you’ve got a print that you don’t want to chop up and match, right?
p.s. i also really appreciate how you show that a pattern piece that looks neat and tidy and ‘by the book’ can still look really crummy *on the body*. Unless we are framing these things and hanging them on the walls, i believe all garments should be judged by how they look when worn by a human being.
That was one of the big confidence killers for me in my earlier years of sewing. I couldn’t understand why, when it appeared that I was doing everything correctly, I still wasn’t getting the results that I wanted.
I think that one of the biggest frustrations of curvy sewists is that fitting books/tutorials work great up to a point, but then you pretty much have to figure things out for yourselves. On top of that, I think that as women, we tend to blame ourselves and think that we’re doing something “wrong”, rather than that the methods that we’re using have limitations.
Excellent introductory post! Lucky us 🙂
Very excited to see more on dart rotation! Learning about dart rotation decades ago completely changed how i alter patterns and my fitting results really started to take off.
These days i find myself specifically looking for patterns which will accommodate some rotation. Being able to distribute the alteration gives a much more pleasing aesthetic result as well as making the alteration itself easier to perform (you’re not having to correct those crazy armscyes like you showcase in this post!).
Very glad to see so much interest in this topic, too. Three new posts have popped up just as i’ve been reading and writing – go Michelle!
I completely agree. When determining whether or not I’m going to buy a pattern, I always ask myself, “How would I FBA this?” followed often by “And where would I rotate at least part of a dart, if I need to?”
Can’t wait to see the next post!
What about splitting a dart into two adjacent darts? Does that work?
You can definitely split a dart into two, and that’s one of the posts that I’m currently working on–the “dart rotation” post. I’m not quite sure what you mean by two adjacent darts, though.
Whenever I’ve tried this it’s looked terrible so I’m waiting in anticipation of how to do it correctly!
I think a lot of it depends on where you rotate the dart and the general design of the garment. I’ll be talking about that a bit in my post.
My first few attempts to partially rotate a dart definitely created some oddities–it took a bit of trial and error to come up with a few locations that I tend to lean on more.
Can’t wait to read it !
I mean rotating out part of the dart so that you end up with two darts next to each other, coming from the same seam, eg the side seam or waist, rather than two different seams, e.g. The side seam and waist seam. I imagine it’s how the BHL anna bodice would look if sewn with darts. When I’ve tried it, it just looks so wrong on paper I haven’t been able to bring myself to sew it up.
I’ve sewn one or two patterns with double-darts like that (one of Jennifer Lauren’s patterns has it), and the popular Simpliciy 2444 pattern has two parallel darts. When you tried it, did you have the two darts parallel, or both pointing to the apex?
Parallel but they were still quite large in uptake so the points of the darts were spaced either side of the bust apex and so it just looked odd odd odd
Thank you. I’m looking forwards to your next post. I’m keen to learn more about partial dart rotation as this may help give me more hip space (pear shape). I reckon the Y shape wouldn’t work for me as I often have to reduce excess fabric in upper chest. I’ve only done traditional FBAs so far, as shown earlier in your post.
Yeah, I’m not a huge fan of the Y-Dart on myself unless there’s nowhere else to rotate the dart. However, I know that a lot of women love it and swear by it. I could be way off base, but I suspect that on me, part of the problem is that I’m short and therefore adding that extra fabric over a short horizontal distance. I think it would be interesting to poll the heights of women who have tried the Y-Dart and see if there’s any correlation between (torso) height and how well the Y-Dart has worked out for them.
I’m 5′ 11″. I am long between shoulder and bust apex but not wide – in fact I’m slightly hollow in that area. I have to lengthen in that area, but need to be careful about excess fabric. My cup size is DD/E.
Hi, Michelle! I have to put my two cents’ worth into the discussion. I second your advice to start with a pattern size based on the high bust measurement. But I also suggest sewers look at their over-all weight distribution, and not be afraid to combine methods, if needed.
I have an 8 inch difference between my high and full bust measurements, and I’ve found that I need to do a combination of a cheater FBA and then rotating part of the actual darted FBA into a second dart (usually at the armscye, and usually at the point of the acute angle). This is because I’m built with a lot of my bulk from front to back, rather than side to side – if you sliced me horizontally, I’d be more of a circle than an oval (like most women). I have narrow shoulders, so to get a good fit through the shoulder and upper chest, I need a smaller size than even my high bust measurement would indicate.
So glad to see you here. Your daughter is getting so big!!
Sounds like we have similar fitting issues! It’s sure a pain to do fittings when I’m super picky about getting it right. I did a dart rotation in a costume I made recently and was pleased with how it turned out, but I think a combination will work best for regular clothing.
I know. I really envy those sewers who can make a garment right out of the envelope. Never could do that, even when I was (relatively) slender. I really dread always making a muslin, but it’s a necessity if I’m going to end up with anything wearable.
Oh absolutely. You need to do what’s right for your own figure. I have back fat, so I usually end up making up some of my high bust/full bust difference with a broad back adjustment.
With this post series, I’m trying to start of with the more simple, straightforward topics and plan to have my posts build on each other.
I can’t wait for the next post! I reallllly neeed this alteration as I tend to add 3″ for my FBA and have been noticing dart problems. I will try the rotation to move some of the bulk of the big honking dart. Do you ever find that the dart also ends up far too long? I find that it’s not ending in the right place and it’s ending too high.
I am really excited to learn more, since we have a very similar issue. 🙂
I find that I need to back the dart point off of my apex by about 2.5″, personally. This amount varies by person, depending on how round your breast is (and can be somewhat determined by the bra that you’re wearing).
If your darts are pointing too high (i.e. to a point above your actual apex), that’s a different issue indicating that you need to lower your dart. That’s super easy to do and is something that I’ll be covering in a later post.
That’s awesome. I am looking forward to the later posts on this. I’ve only recently started some research on dart manipulation and it doesn’t really talk about fixes for large busts. This is going to be such a useful series for me! So very happy you are an editor now. <3