Full Bust Adjustment Guide | Giant FBA on a Dartless Knit Bodice (aka: Adding a Dart When You Need One)

The deal with Giant full bust adjustments

Being pregnant, my boobs have grown 6 inches in the last 6 months — I’ve gone from a garment sewing DD or F cup to a garment sewing K cup. (Remember that bra cups aren’t the same as your garment sewing cup size! Learn more about determining your garment sewing cup size here!)

Even with the ~80 designers on the Busty Pattern Database who draft for larger cup sizes or offer cup options, only one offers a cup option that fits me — Porcelynne’s I/J cup in her tank series is just right.

So full bust adjustments and I have become best friends lately. And not just small, 2-3″ FBAs, but BIG HONKIN FBAs. Even on a DD garment cup size pattern — the largest cup size offered by a substantial number of designers — I need a 6″ full bust adjustment (3″ per side). On a B cup pattern — the size that most designers draft for — I need a 9″ FBA (4.5″ per side).

The trouble? No fitting book or FBA tutorial I’ve seen really gets into what it looks like when you’re adding this much.

Which is annoying because it looks different. It can look a lot different.

So I’m going to start showing you what my FBAs look like when I’m adding 6-9″ to my patterns.

Fitting the Perfect Maternity Tee

This particular FBA was inspired by my search for a perfect maternity tee — partially because I need a lot of new shirts right now, and partially because I’m planning a bodycon style dress for my baby shower, and I needed a base pattern.

I started with the Agnes Maternity Top from Tilly & the Buttons (which also has a non-maternity version), but this tutorial can easily be used for any number of dartless knit top patterns, such as the Cashmerette Concord, Itch to Stitch Glenelly, or the Laela Jeyne Indigo Bodysuit.

Do I have to add a dart?

Okay, I’m really sorry. But I have bad news. Yes, if the difference between your high and full bust is more than, say, 7″ (17.8 cm), you’re probably going to need to add a dart, even to a knit bodice — especially if you’re hoping for a fitted look.

If you’re okay with the bodice being a more loose fit at the waist, you might be able to get away with rotating the dart out and easing the side seam — a process we’re not going to get into today. But, if you want a fitted look, it will be simply impossible to ease your front and back side seams together after adding so much. (Trust me, I tried. A lot. It doesn’t work.)

That said, I really don’t think the dart is super noticeable, and I promise it’s less noticeable than the armpit wrinkles that result from ill-fitting knit tops. (Tell me if you think the dart is noticeable in this side view!)

Getting prepared for your FBA

Choosing a base size

We’ve talked about this before, but I want you to start with your high bust measurement, braless. (The reason we take this measurement braless is because you’re trying to capture as little breast tissue in it as possible, and bras push breast tissue up!)

If you’re working with a pattern that lists high bust measurements on its size chart, that’s great! The work is done for you! Choose your size based on the one that corresponds with your high bust measurement.

But, if your pattern is like the T&B Agnes, you’ll need to do a little math, which will require you to know what garment cup size the pattern is drafted for. In my case, I reached out to T&B and was told that their maternity patterns are drafted for a D garment cup — 4″ difference between high and full bust. So I knew I needed to add 4″ to my high bust measurement. (If you’re working with a usual pattern with a B cup draft, you’ll add 2″ to your high bust measurement.)

For me the math looked like this: 35″ + 4″ = 39″

This number should then correspond with the bust measurement on the pattern.

On the Maternity Agnes, this put me between a size 4 and 5. Because I wanted a more fitted look, I went with a size 4.

How do I know how much to add? Math time!

On a woven garment, this is easy. If the Maternity Agnes were woven, I’d simply take my full bust measurement minus the full bust measurement for which it is drafted, and that would tell me how much to add. Divide this by two, and you get how much you need to add per side.

For example:
My bust: 46″
– Drafted bust: 38″
= 8″
Divided by two (since there are two sides to a front bodice!) — 4″ per side

However, I don’t like to do things this way for knitted/stretch patterns. My reluctance comes from the fact that stretch percentages mean you’re really adding more. For example, if your fabric has a 50% stretch, adding 4″ total is really adding a maximum of 6″, while adding 8″ total is really adding a maximum of 12″ — that’s a 6″ difference in maximum stretch for what’s supposed to be a 4″ difference. This problem is exponential, so the larger your FBA the more skewed things can end up being by simply adding inches like you would with a woven.

So I like to look at percentages. Enter the finished garment measurements.

For the size 4 I’m making, the finished bust measurement is 36.5″. It’s drafted for a 38″ bust. I want to figure out what this is as a percentage, so I’ll take 36.5 divided by 38 to get 96% — meaning this is drafted for 4% negative ease.

Now, I need to figure out what 96% of my full bust is: 46″ times 96% (0.96) = 44.16″. I’m going to go ahead and round that down to 44 to give me a nice even number (and I can confidently do that because I know my knit stretches plenty to cover a .16″ reduction). This is what I need my finished bust measurement to be: 44″.

Next, I’ll need to figure out how many inches that has me adding, so I’ll subtract the pattern’s finished bust measurement from my own needed finished bust measurement: 44″ minus 36.5″ = 7.5″. This shows me I need a total of a 7.5″ FBA, so 3.25″ per side.

If reading this is confusing and you’d like to see a video version, I walked through this process on instagram live here!

Doing the FBA

Finding your apex

Now that you’ve done your math, you can get working with your pattern! Here’s what my pattern looked like before I made any changes:

You’ll notice there’s no apex marked on this pattern. No worries! We’re going to find our own apex.

Put on a top that’s made from a fabric with a similar stretch percentage. Using washi tape, mark where your bust is fullest — this is sometimes the nipple, but not always. Look for the “peak” of your “mountain.”

(My washi tape is really lightly colored! I apologize that it’s hard to see here!)

Now, take off this top and fold it at center front. Lay the folded top under the front bodice pattern, matching the shoulder seam and center front (being mindful that seam allowances mean your pattern should slightly overhang the shirt).

You can see my washi tape through the pattern paper. This is where I’m going to mark my apex.

Preparing the pattern

Now that we’ve marked the apex, we’re going to cut the pattern at the waistline. On the Agnes, the waistline (or, in this case since it’s a maternity pattern, the empire waist) happens to be at the lengthen/shorten line, but this may not always be the case. Cut the pattern at the narrowest part and put the bottom of the pattern aside. We’ll come back to it later. (If you’re working with a bodice pattern that ends at the waist, great! No need to cut at this step.)

Now, we need to make some markings. First, draw a vertical line, parallel with your grain line, from the bottom of your pattern to the apex. We’ll call this Line A.

Now, draw a second line from your apex to about 1/3 of the way down the armscye. We’ll call this Line B.

Some tutorials will tell you to put this mark lower on the armscye. While this works for those who need to add fewer inches, for larger FBAs, putting this line low on the armscye causes too much armscye distortion, so higher is better.

Important: At Line B, mark your seam allowance. This will be very important at a later step.

Third, you need to draw a line from your apex to the side seam. This is Line C.

You can really put this anywhere along your side seam that you’d like, but keep in mind that where you place it on the side seam will essentially end up being the top of your bust dart. I like to make mine slightly angle upward, but only slightly. If I wanted a fully horizontal dart, I’d need to make this perpendicular to my grain line.

Finally, mark a Line D perpendicular to Line A about an inch above your waistline.

Cutting the Lines

Now it’s time to start cutting! But, before we do, do yourself a favor and stick a piece of scotch tape on your apex and on the seam allowance mark at the armscye.

Okay, now, starting from the bottom of the bodice, cut upward through Line A to the apex, then from the apex through Line B — stopping at the seam allowance mark. From the opposite side, starting from the armscye, cut through Line B, again stopping at the seam allowance mark.

Your pattern should be hanging on by a thread of paper at the seam allowance mark, allowing you to pivot at this point.

Now, starting at the side seam, cut through Line C, cutting to but not through the apex — creating another pivot point where the paper is holding on by a thread.

Your pattern will look like this:

Adding inches

Now it’s time to add some inches! I like to tape down the center front side of my pattern (on this pattern, the right side of the picture) along Line A onto another piece of pattern paper. I then draw a line however many inches from Line A on the extra pattern paper:

This line gives me something to line up the side seam side of Line A with, which is the next step.

Pulling the side seam side (here, the left of the photo) down and out to match that side of Line A with the line you just drew.

Note: You’ll see I’m only adding 3.5″ here, though earlier I said I needed a 7.5″ FBA, so 3.75″ per side. Well, that was a mistake. But since the pattern uses fabric with at least 50% stretch, I decided to just rock a bit more negative ease and not worry about it.

Evaluating Armscye Distortion

So this is what my FBA would look like. If I was adding fewer inches, I’d tape it down and call this my new pattern, essentially. But I’m adding a lot of inches, so I need to evaluate something first: How much did my armscye get distorted?

Depending on the pattern, the armscye distortion might be minimal and totally okay! In this case, tape everything down and use this as your pattern!

But, as you can see here, I got a lot of armscye distortion. It’s basically a J pattern, and I know that’s going to be super uncomfortable. But there’s a solution!

Doing the Y FBA

We’re going to add one more line. Draw a line from the apex to the middle of the shoulder seam — usually there’s a notch here, and if so, use that! This will be Line E.

Just like with Line B, you need to mark the seam allowance on Line E.

Now, cut from the apex along Line E to but not through the seam allowance mark. Then cut from the top of the shoulder along Line E to but not through the seam allowance mark, creating a pivot point with a thread of paper at the seam allowance.

Again, spread down and out to match the side seam side of Line A with the marker you created earlier to show how many inches you’re adding.

At this point, you need to decide how much of the added inches you want coming from the armscye versus the shoulder/high bust area. In the above slides, you can see how you can manipulate where things lay to have more of the added inches be along Line B or along Line E.

This is all about knowing your body. Adding more to Line E — like in the second picture — prevents more armscye distortion, but adds more width at the high bust/chest. Adding more to Line B — like in the third picture — creates more armscye distortion, but doesn’t add as much at the high bust/chest. Or you can choose something like the first picture, with roughly equal amounts distributed between Line B and Line E.

I don’t like to have too much added at the upper bust for my body, so I lean toward adding more to Line B than Line E — adding just enough to line E to avoid significant armscye distortion. I went with something like the third picture.

Once you have everything where you want it, go ahead and tape everything down, just being sure not to tape along Line A below Line D.

Adjusting length

Now we need to bring the center front down to the level of the side bodice. Extend Line A on the center front side down to be even with your new waistline from the side seam side, and draw a horizontal guideline at the same level as your new waistline on the side seam side.

Now, cut along Line D, completely detaching that bottom piece. Tape this down along the guidelines you just created, like so:

This is what we have so far, and we’re pretty much there!

Finishing Touches

Smoothing the armscye

Now we need to smooth out the armscye. You can do this by eye (which is honestly what I usually do), or break out your French curve to do it *technically* correct.

At this point, I like to drop my armscye just *a tiny bit* — like 1/4 to 3/8″ — making sure the armscye remains the same total length by measuring where I’ve dropped it.

Drawing your new dart

You now need to draw your new dart. Start by measuring the opening of the triangle you’ve created, and marking the center point.

Now, draw a line from this center mark on the dart to the apex. You’ll see here I moved my apex a bit. This was an experiment, and I wouldn’t recommend it. Just use the apex you marked — since the dot has been divided, choose the one on the center front part of your pattern.

Now, mark a spot along this center dart line some inches from your apex. The number of inches depends on the size of your bust. Here’s what I’d recommend as a starting place:

I+ garment cup9″+ (22.85 cm+) full/high bust difference2.5″ (6.35 cm)
G-H garment cup7-8″ (17.8-20.3 cm) full/high bust difference2″ (5 cm)
DD/E-F garment cup5-6″ (12.7-15.2 cm) full/high bust difference1.5″ (3.8 cm)
D garment cup or smaller4″ or less (10.2 cm) full/high bust difference1″ (2.5 cm)

So I made my mark 2.5″ back from the apex. This will be my vanishing point, or where the dart will actually end. You usually don’t want the dart ending too close to your apex, because this will make your bust look verrrrry pointy. (If pointy is the look you’re going for, then make your vanishing point closer to your apex!)

Now, you’re just going to connect this vanishing point to your dart legs. This is your finished dart!

Note: Do you need to split your dart? I answer this question visually. My dart was about 6″ long and 3-5/8″ wide, and, looking at it, I thought it would sew up fine. If your dart looks really wide, you may want to split it into two darts. This post goes over the how-to on splitting darts.

Truing the Side seam

We now must true our side seam. To do this, fold your dart as if it was being sewn. I prefer to have my dart go upward rather than pressing it down, as most instructions indicate. I find this makes a smoother line for larger busts. (Thanks to Cashmerette for the tip several years ago!)

You can either fold your dart up or down. It’s up to you.

I like to tape this shut using washi tape, so it stays closed while I deal with my side seam, but using a tape that won’t rip the paper when I remove it.

Use your French curve or eyeball a slightly curved line, connecting the armscye to the lower side seam.

You’ll see that I had a big jump from the upper to lower side seam. Since you can always remove but can’t add, I chose to go with the outer side seam — so the placement of the lower side seam. It’s worth noting, however, that I ended up skimming about 3/8″ off this spot when I sewed my muslin, so I probably could have/should have gone with the smaller of the lines — where the side seam is on the upper part.

Truing your waist

As you may recall, you’ve added inches (in my case, 3.5″) to your bust level down — including your waist. Well, if the waist was the correct size on the original pattern and you want the bodice to be fitted at the waist, this isn’t going to work. We need to reduce the waist.

On a woven, this would be easier. I’d recommend taking a bit from the side seam and adding a waist dart or two.

But here, I didn’t want to add a waist dart. This is a tee shirt after all! So it’s going to have to all come from the side seam.

To do this, mark along the waistline 3.5″ (or however many inches you added in your FBA) inward from the side seam. Draw an S curve, starting at your bust height and ending at your waist marker, like this:

You can do this with a French curve or by eye. I started with my French curve and ended by eye, which is why my line is so ugly 😂

I also had a bit of an extra challenge because I was making this with an empire waist rather than a natural waist, so that gave me less space to gradually skim off the side seam than you’d have using a natural waist. If you’re using a natural waist, this line shouldn’t look quite so angular.

Now, to finish truing the dart, cut along this line:

Open your dart back up, and you’ll see your finished side seam!

Reconnecting with lower pattern

Now our last step is to reconnect our upper pattern with our lower pattern!

Essentially, you just need to match your lower pattern to your upper at the side seam and center front.

At this point, I also do a bit more truing of the side seam and cut it out:

You’re finished!

Yay! All done! Here’s my finished pattern piece:

Now cut and sew the pattern as usual. If you have an extreme angled side seam like me, it might be worth reinforcing the side seam at that point with some seam tape or elastic, just to add some strength since the force of the fabric is a bit wonky there.

I feel pretty awesome about this pattern! I can’t wait to sew up my baby shower dress 🙂

If you follow Sew Busty on instagram, you’ll know that I ended up needing to tweak the sleeve for my fuller biceps, but the bust was on point!

Advanced Fitting Series with Designer Stitch | Contouring Gaping Armholes with Darts

Hi Ho my friends. Ann here from Designer Stitch and I am back with another fitting post in the Sew Busty fitting series – answering your questions about any fitting dilemmas or problems that you may encounter when sewing all of your fabulous me-made clothing.

And I bet you cannot even GUESS what I am going to talk about today?.

You guessed? – well YES – my favourite subject of all time. DARTS!!!

As you may know I have a huge love affair with darts. And all things DART related.

Darts are the ESSENTIAL fitting tools of a well made and well fitted garment.

So today I put on my My Teachers Hat 👩‍🎓 – this is what I call my how-to’s over in my Designer Stitch Pattern Support Group over on Facebook. Why not come over and say hello to us all. xx

What are Darts?

The above image – left – details the ABSOLUTE minimum of dart placement that you should have on a bodice. The minimum for fitting – and I say MINIMUM for a reason – are the side bust darts. They help contour the garment – alleviate drag – and also stop the centre front of a garment lifting. 

The above image – right – are the minimum CONTOUR dart/wedgies that you would need to have if you were fitting a sleeveless garment with a lowered neck. These are called contour darts or wedgies – as they facilitate the contouring of the garment over and around your entire bust mound. 

The darts added to the armhole stop your garment gaping around the side bust mound. The darts added to the neckline stop the garment gaping as the bodice comes off its contour of the bust mound into the flat surface of your upper chest area.

But Why Darts?

The image on the left shows a side view and a straight piece of cloth. A body is 3 dimensional yet the cloth is 2 dimensional. 

When the cloth has to fold over the body it creates folds or wedgies on itself at its hinge points. So really the folds and wedgies it makes are just the DARTS that we need. The cloth tells us what it wants to do. 

What Happens When There are No Darts in Play?

A garment that has no darts in play will never EVER fit your body properly. And the above images are perfect examples of this.

Over on the Sew Busty Facebook Group our Anouska W posted the above pics asking for fitting advice. The image on the left shows massive gaping in the side armhole. It is quite obvious.

The fullness in this area creates a type of “wing” that can be contoured back into the bust mound with shaping. And what shaping do we use – well, DARTS OF COURSE!!

The image on the right shows that the toile that Anouska made is actually telling us what it wants to do. The fullness and folds of the fabric are showing us that it wants to fold down on itself – hence creating that all important contour – in the form of a dart. 

Two pattern pieces are shown side by side. A caption reads "The above are the pattern pieces used. While there is provision of a "full bust fit" the shape has been widened only. Not a single dart for shaping is to be seen anywhere on the patterns."

I asked Anouska to send me a pic of the pattern pieces that she used. As you can see above there are no darts to help contour the pattern piece around the body. There is a separate pattern piece provided for a “full bust” – but this has just been done by widening the pattern.

Not a single dart for shaping is to be seen anywhere on the pattern. 

Adding Contour Darts to Your Pattern Piece

Two pattern pieces are shown with darts added at the armscye and side seams. A caption reads "The minimum required for this pattern is a side bust dart regardless of the standard fit or full bust fit. Each fit must have its own dart sitting in the side seam. Then to facilitate shaping a contour wedge/dart should be taken in the armhole for bust mound shaping."

The absolute minimum required for this pattern should have been in the form of side bust darts regardless of standard fit or full bust fit.

Each fit must have its own side bust dart. And the full bust fit would have a bigger side bust dart than the standard fit.

Then to facilitate the shaping around the side bust that Anouska’s toile is telling us it needs – a contour dart/wedgie – should be then taken for side armhole bust mound shaping.

And you may ask – How much should this be ? The toile will tell you.

Whatever you have pinned out to create your new contour dart is the full dart value amount.

Pinning out shape on your toile is the best way to ascertain how much shaping is needed in any part of the fitting garment. 

An image of a pattern piece with side bust darts, diamond waist darts, and armscye darts is shown. A caption reads, "This is the front of my Raven cami. The armholes have already been controured as you can see from the angle of the side seam and the curve of the armhole. If any additional contouring is needed you draw your contour wedge in position that you pinned your toile out – draw it onto your pattern as if it was a new dart.

When adding your contour dart/wedgie to your pattern you must ensure that the dart is angled correctly – again your toile will tell you – and that it finishes its length at the bust apex point.

The above image is the front of my Raven Cami/Slip Dress pattern. I have already contoured my armholes with a fitting dart as you can see from the angle of the side seam and curve of the armhole.

If you need additional contouring you draw your contour dart/wedgie in position – as if it was a new dart – to the length to the apex.

An image of a camisole pattern with darts at the armscye, side seam, and diamond waist darts is shown. A caption reads: "The new contoured darts in the armhole can then be shortened back from the apex point – anywhere from 3 cms or more – or they can be pivoted back into the existing side bust dart. But a WARNING – do not pivot all of your contour darts into the side bust dart – making one big huge dart. If the dart is too big it will not sit correctly and you may end up with a massive pointed cone shape sitting off your side seams and your side bust mound. Bust darts DO NOT do all the work for fitting your body. Your body needs shaping over ALL of its contours.

For the final pattern you now have a few choices.

You can either leave your new armhole dart in place as it is – but if so you must shorten this new dart back away from the apex to avoid pointy “boobs.” They are usually shortened back a minimum of 3 cms (1 1/4″) but this will be dependent on how it sits on your body. It may need more length or even made shorter. See what the toile is doing and then make your final decision. 

Alternatively the armhole dart can be pivoted back into the existing side bust dart. But a HUGE WARNING!!! DO NOT – and I repeat DO NOT pivot all of your fitting darts into your side bust dart. I see countless blogs and YouTube instructional videos advising this – and it is so so wrong.

Pivoting all darts into a side bust dart not only results in one massive DART – but you will have a dart that doesn’t sit correctly and may end up with a HUGE pointed cone shape sitting off your side seams.

And one thing I HATE that makes my eyes scared – it is pointy BOOBS. 

Side bust darts should not – and DO NOT – do all the work for fitting your body.

Your body needs shaping over all of its contours.

Hence why darts are needed in key fitting areas. 

I hope that you have learnt something by reading my story and please shout out if you have any thoughts to share.

The good thing about sewing and fitting our bodies – we always learn NEW THINGS.

Love to you all and please stay safe and well everyone xx

Cheerio my lovelies
Ann at Designer Stitch xx

Sloper Series: Using Your Bodice Sloper for Well-Fitting Bust Darts WITHOUT a Muslin

Back in May, I guest blogged for the Curvy Sewing Collective on drafting a bodice sloper for big boobies. In that blog, I experimented with four different sloper drafting methods, and ended up with a well-fitting sloper at the end! Maybe you followed along and have your own bodice sloper now, too! Well, what do we do with these slopers?! Let them collect dust?! I THINK NOT. In this new Sew Busty Sloper Series, I’ll talk you through different ways to use your sloper – from pattern alterations to drafting. See the whole series here.

Today, we’re going to talk about using your sloper to modify bust darts on any bodice pattern!

Now, I want to start with a note: I am not an expert seamstress, fitter, pattern maker, etc. What I am is a home sewer who has spent a lot of time reading and experimenting. And from those experiments, I’ve determined that some of this is more of an art than a science.

With that stated, let’s get started!

For today’s experiment in getting well-fitting darts without a muslin, I’m going to be using Designer Stitch’s Eden Jumpsuit. This is an older Designer Stitch pattern, dating back to 2018, but goodness, it’s on trend for today, don’t ya think?

Lindsie, a white woman in her 20s, stands on a sidewalk in front of a wall that is partially wood and partially marble tiled and models a jumpsuit. The jumpsuit is sleeveless and 7/8 length and is made from a tan-colored material with black outlines of hands throughout. Lindsie has her hand on her sunglasses and looks in the distance. End.

So, to get started, I cut the pattern according to my measurements, which, for this pattern, was a size 3DD. In Designer Stitch, I usually wear a 3DD graded to a 4 at the waist, then back to a 3 at the hip, but since this pattern has an elasticated waist, there’s lots of ease there. So I just cut a straight 3DD, no grading.

The first thing I needed to do was adapt my sloper to have darts that match the Eden. My sloper – the version I posted on the CSC blog – has a side bust dart, a shoulder seam bust dart, and a waist dart. But the Eden only has a single bust dart. So I first made a sloper version with a single bust dart by rotating my darts into a single dart.

I’m not going to go over dart rotation in this post, but suffice to say it’s SUPER EASY. There are a few ways to move darts, and I prefer the pivot method, shown in the second part of this video:

Now, you might be thinking, “But Lindsie, some of the shaping that would normally rely on darts is surely happening through the elasticated waist, right? How do you account for that?”

Well, remember when I said this was an art, not wholly a science? Let’s just keep going and see where things lead.

The next thing I’m going to do is place my newly-created single-dart sloper over my front bodice pattern. In this image, I’ve marked the correct bust point and the dart legs in pink.

You’ll notice that all the lines of my sloper are just slightly inward of the outer edges of my pattern. This is because my sloper has no seam allowances, while the Eden has 1/2″ seam allowances. So I placed my sloper edge roughly 1/2″ inward from the edge of the pattern.

You will also notice that The center front of the pattern piece is angled differently than the center front of the sloper. This is because the pattern has an elasticated waist, while my sloper is designed to form-fit my body.

Okay, so what can we learn from this?

Well, the biggest thing I noticed is that my bust point, marked here with a pink X, is about 1/8″ lower and 1/2″ inward from the bust point of the Eden pattern. You can see this a bit more clearly on the following picture, where I’ve marked the Eden’s bust point in blue:

Another thing that you might notice is that the angle of the bust darts is different on the Eden than on my sloper. Here, I’ve traced the Eden bust darts in blue:

What you may or may not be able to see in this picture, though, is that the bust darts – while ending at a slightly different apex and having a different angle – are actually about the same width.

In fact, moving my sloper to have its apex match the Eden’s apex and rotating to have the dart legs match, I could see that the darts were actually just about correct in size.

So, my biggest issue was the apex being ever so slightly off. (And frankly, this isn’t much of an issue, and this whole process really showed me why Designer Stitch patterns are some of my favorites … their block appears to match my bust very well).

To fix this, I drilled through the apex and marked the Eden pattern underneath. Below, you can see my new apex drawn as a purple X:

Now, this is the tiniest apex change. But, for a near-perfect fit, I still wanted to make it!

The most correct way to move the apex down is to cut out the dart and move the whole damn thing down. You can see a tutorial on this from the Curvy Sewing Collective here. Only then would we lengthen the dart to account for my closer-to-center apex.

But, I’m lazy, this was literally a 1/8″ lowering, and – looking at my sloper bust dart angle – I knew that I like my darts to be at a slightly more downward angle. So instead, I marked my dart’s disappearing point 1-1/4″ from my apex, and redrew the damn dart.

Here, you can see me trying it on before adding the elastic or zipper. This photo also happens to be helpful because it shows how the bust fit before I wore the thing and introduced mega wrinkles. (Ohhh cotton poplin, how I love you, but how you also get SO WRINKLY.)

That’s literally it, folks. That’s the dart I used. I did try the bodice on after sewing the darts, and ended up lengthening the darts by about 1/4″ and curving the ends – something I often do with darts, and something that didn’t surprise me, as I prefer my darts to end about 1″ from my apex, while Ann from Designer Stitch ends her darts 1-1/4″ from the apex.

It has pockets, y’all!

I am absolutely chuffed by the near-perfect fit on this jumpsuit!

How have you used your sloper to achieve better-fitting busts on your makes? Tell me in a comment below or post about it in the Sew Busty Facebook group or subreddit.

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Advanced Fitting Series with Designer Stitch | Darts: Essential Fitting Tools

The Advanced Fitting Series aims to answer all your intermediate-to-advanced fit questions. It is a collaboration between Sew Busty and pattern designer Ann Grose of Designer Stitch. Have a question about fit? Email it to fitquestions@sewbusty.com and you might see it featured!

Greetings my lovelies – Ann here from Designer Stitch. And welcome to my first blog post as part of the Sew Busty Advanced Fitting Series – answering your questions about any fitting dilemmas or problems that you may encounter when sewing all of your fabulous me-made clothing.

Over in my Facebook group I call this – My Teachers Hat 👩‍🎓 – so welcome everyone.

As this is my first post about fitting I am going to talk to you about my FAVOURITE subject – DARTS!!
You may have seen a few previous posts over on my blog discussing darts so you will know that I truly adore them.

Darts are an essential fitting tool that is needed in a sewing pattern. They are key in getting the correct fit of your sewing pattern as they enable the fabric to shape and sculpt itself around your body.

Darts give a fabulous silhouette to the garment to enable you to get the best fit possible.

What do darts do?

Darts are a contouring tool – where a flat length of fabric is shaped to contour around your body.

Darts are essentially a wedge of fabric – shaped liked an extended triangle – that is stitched in your fabric to convert that length of fabric – a 2D shape into a 3D shape.

Where are darts found?

Dart areas can be found throughout the body. Bust darts, waist darts, back shoulder darts, front neckline darts.

Even the shaped side seams of a pattern are essentially darts – except they are split apart to create individual front and back side seams.

Darts don’t always have to remain as darts. Darts can be converted in flare, gather, pleats and tucks.

What happens when there are no darts in play?

The above images are my render of two photographs that were submitted to Sew Busty where the submitter was asking about choosing the appropriate size of the pattern.

Her measures were High Bust = 36″, Full Bust = 38″. And she stated the pattern was drafted for a C Cup. (The body measures as detailed warrant a B Cup). She wondered if she needed a full bust adjustment, due to the wrinkling under the bust.

Regardless of this sizing – if you are trying to drape a flat 2D length of fabric over the body you need some type of contouring device – hence DARTS!!

And you may be saying – Why Darts? The images above indicate that the center front (CF) is lifting and there are drape lines radiating from the side seams to the bust point.

What is happening is that the bust is projecting – dragging the fabric – and then lifting the front hem line to accommodate the projection of the bust mound. (Note: the garment fitted the wearer except the drape lines were very visible. They were drape lines – not drag lines which indicate a garment that is too small).

To offset the front hemline lifting – and the drape lines radiating to the bust point – the length of the front pattern piece needs to be increased.

The above image indicates two lengths of measure – one from shoulder – over bust point – down to hem. The second – from shoulder but straight down without going over bust point.

You can see how much longer the length is that is going over the bust point – than the straight vertical measure.

The above image shows the more the bust projects – the need for a greater length of front pattern piece.

Adding extra vertical length to the front pattern will then allow the sewn piece to contour nicely over the body – but to do this we have to add shaping to that pattern piece to offset the extra length.

And that will be remedied by our friends – DARTS!


To add extra length to a pattern piece – to facilitate contour – the entire front needs to be lengthened – but as the center front (CF) of the pattern has to be cut on the fold the entire front piece needs to be split and extra length added in.

And so our lovely dart friends come into play xx.

The extra length added to the vertical front of the pattern is taken up with a side bust dart.

The side bust dart is placed at an angle – generally 8-9cms (3 – 3 3/8″) down from your original armhole/scye line – angled to the junction of your front bust depth/bust point separation known as the bust apex (bust point).

Then this dart is usually shortened back around 3 to 3.5cms (1 1/4″ to 1 1/2″) from your bust apex/bust point (but this can be variable)

Adding bust darts to a pattern piece is relatively easy – if you have your correct measures – and of course know how much is needed.

From the original photo that I drew the above images from I calculated that the OP need to split and add approx 2.5cms (1″) to her front length.

I hope that you have learnt something by reading my story and please shout out by commenting below if you have any thoughts to share. And don’t forget to submit your fit questions to fitquestions@sewbusty.com!

The good thing about sewing and fitting our bodies – we always learn NEW THINGS.

Love to you all and please stay safe and well everyone xx

Cheerio my lovelies
Ann xx