Wednesday, December 3, 2014

Subtleties of Drafting: Darts Part II - Draping Darts

Welcome back to our micro-series on darts! 
If you missed the introductory Part 1, you can read it here.

Today, we are going to drape Fleur

First, a disclaimer and a caveat.

Disclaimer: I don't usually make patterns by draping; I almost always draft them from slopers. However, in the process of refining the fit of a sloper or paper pattern or even fabric already cut into pattern pieces, I do a little draping. It isn't an alternative pattern-making method so much as it is a technique for manipulating fabric to fit contours. Unlike drafting, which begins on paper, draping must be done with the fabric itself. Nobody taught me to drape this way, and I did not learn it from a book or a blog or a fancy fashion course; everything I am sharing in this post is absolute common sense and nothing else. 

In the world of pattern making, it is the creation of the paper patterns, not the beautifully draped garments themselves, that is the ultimate goal. I've shown you before here and here how to make darts on paper patterns. However, darts may be difficult to visualize on paper, so today we will create them in fabric instead and move them around and do all kinds of fun stuff with them. I recruited Fleur as my lovely assistant - we will be draping her contours into a close-fit sloper.

The caveat: Although Fleur is my custom-fit mannequin, we are not 100% of the same shape, nor do we have truly identical contours. She is made of canvas and cardboard and I am made of fat and (one hopes) muscle. Her curves are more proportional and gradual while mine are bulgy and scooped. So today's fabric sloper made to my measurements and draped on Fleur will not look as snugly-fitted as if it had been draped on me. And there will be little wrinkles and the dart points will be closer to the bust apices than they should be and all kinds of other imprecisions in the draping process. So just bear in mind that this is only an approximation of true draping so as to illustrate how darts are created.

And now, let's begin with some foundation principles -and these apply to both drafting and draping. 

No matter what you do to adjust or adapt a sloper or pattern, there are some lines that remain fixed and serve as baselines for reference and symmetry. One of these is the center front line, that runs down the vertical midline of the front of the body.

Another is the center back line, that runs down the vertical midline of the back.

I hand-basted those two lines in orange thread onto Fleur, so I would always know where the midlines were. The third reference line (at least for today's draping exercise) is the shoulder line, which you will see later.

Incidentally- one of the reasons I made Fleur a custom-fit fabric mannequin rather than a duct-taped body form, is so I could sew and pin her at will. You can read about how she was made here, but that is not relevant to this post at all.

One of the first questions I asked when learning to draft darts was, "Where do we put darts? Are there standard locations or can we put them wherever we want?"

The short answer is this: you can put darts ANYWHERE (even on toys). The principle is to put them where there are hollows on the body. 

In the diagram below, the blue shaded areas are the typical natural hollows of a woman's body. They vary in degree and coverage, but that's where they are located. When flat fabric lies over this body, it has to have darts in those hollow areas in order to fit those contours. 

Here is the side view of those front and back contours, with the darts (in red) located where they best shape the fabric to fit those contours. 

The green arrows below indicate the hollows at the side of the body. Although these can also be shaped by darts (and we will discuss that later in this post), these hollows are more commonly shaped by curving the side seams of the fabric when it is made into a garment. 

Here is the thing we will be draping on Fleur. It is a one-sided sloper made of random flannel, made to my/Fleur's dimensions. I have omitted all the darts, leaving only flat fabric. I have also sewn the side seams to fit the side contours of Fleur (as we discussed in the paragraph before this), and the shoulder seam to fit Fleur's shoulders.

Notice that the front piece is more bulgy than the back and, in the absence of darts (for now), there is a big crease in its chest area because of excess fabric. This is because the front piece accommodates the bust, which has additional volume. The back, having no bust, does not have this extra amount of fabric.

Finally, I sewed the side seam only up to the waist, leaving the upper portion in the chest area open. This is because we will be pinching the fabric to form darts in the bust area, and we need the fabric there to be movable and unconstrained. Also note that I used very, very wide seam allowances at the side seam - moving darts around changes the shape of the side seam quite drastically, as you will see later, and I needed extra fabric with which to play around.

Let's prep Fleur.

We begin by throwing the flannel sloper onto Fleur and positioning the shoulder seam. Then we pin the center front (CF) of the sloper along Fleur's center front, exactly along the orange basting line earlier mentioned. Do not be alarmed by how the fabric sticks out over the armhole - that's just the seam allowance of the armhole.

I also pinned the center back (CB) line. These three lines - the CF, CB and shoulder - will remain fixed throughout.

You might have heard of people draping entire pieces of flat fabric onto a form or human model to create a garment, in which case they would start with these three reference lines, and begin the draping-and-shaping process. We are not doing that kind of draping today. Instead, we are draping only darts. To remove all other variable sources of shaping while we manipulate those darts, we have used fitted seams at the shoulder, the center front and back, as well as the sides. Therefore, and just for this particular exercise, we have sewn the side seam to fit, and fixed it temporarily in place as shown in the next photo.

Our very first dart, which is the easiest, will be created between those two fixed lines - the side seam and the center back line (red arrows).

Here we go - dart #1!

We begin with the back dart because it has the least possible variation. We drape a dart by pinching

and pinning as much fabric in that area as is needed to smooth the surrounding fabric.

The back of this sloper is now fitted. Easy peasy!

From the side - nice and smooth.

Just for completeness, let's discuss rounded backs, which some people have. 

Here is a diagram of a person's (male or female) back - the blue shaded portions are the natural hollows. Some people have more rounded backs than others, in which case the hollows at the shoulder and beside the armpits will be deeper. The red pointy things are the darts which would shape those hollows. 

Back to our draped sloper now. People with more rounded backs have shoulders that roll forward to the degree that might require a second back dart to pinch the area shown by the red arrow below. An alternative to creating a shoulder or armhole dart - which might be unsightly in certain garments - is to change the shoulder slope of ONLY the back sloper piece. To do that, make the back shoulder slope more slanty (i.e. less horizontal) than the front shoulder slope. It has the same effect as introducing a shoulder dart or moving a back armhole dart to the shoulder area. 

However, Fleur does not need that back armhole/shoulder dart, so let's declare her back successfully darted and move on to her front.

The front body is a lot more complicated than the back, because of the contours of the bust. In the diagrams below, the blue shaded areas are the natural hollows, and the red pointy things are the darts in locations that would shape those hollows. Not all those darts have to be present at the same time - the diagrams simply show possible locations for those darts that correspond to the hollow areas they need to shape. 

Here is the front of the sloper, fitted over the fullest part of the bust. Look at all that extra floppy fabric everywhere else!

Here is that floppy fabric straightened out

to give you a view of all that hollow, empty space (we call it "ease") under and around the bust that we will need to reduce.

The first front dart to create is the waist dart. 

Here is the mathematical explanation for a waist dart.

It's simple subtraction. A first grader could do it. Notice that it isn't an actual formula, which we will learn about in the next post but merely the visual arithmetic illustrating how we know the size of a waist dart. I'm sharing this just in case you think there is some arbitrary chart to follow from some drafting book (to which I gently say, "Um, no."). This concept applies to both the front waist darts and back waist darts and is, literally, the difference between the widest part of the upper body (usually the bust for the front and the chest for the back) and the smallest part of the upper body (usually the waist). 

This is what it looks like in practice:

Like with the back waist dart, you pinch and pin.

Don't be distracted by the actual bust area, people. The waist dart shapes the hollow area UNDER the bust, which is why it ends under the bust.  Therefore, pinch and pin under the bust, so that you smooth the fabric in only the region of the yellow arrows.

Check out the side view - all smooth and neat.

Now we get to the exciting part of today's exercise - the bust dart.

Here is the mathematical explanation for the bust darts:

Again, no need for the crazy "if you are a Cup Size A/B/C/D, make your bust dart 1"/2"/3"/4" wide" charts. We cannot calculate the width of a bust dart by an arbitrary table because it depends on one million factors, e.g.
  • where the bust dart is located
  • how many bust darts there are
  • the length of your bust dart 
  • what sort of muscle tone you have
  • the perkiness/sagginess of your bust

We'll explore the effects of these factors later.

Now, let's do some pinching. The following six examples are ALL bust darts in various disguises.

BUST DART #1: The single armhole dart

We pinch ALL the loose fabric at the side of the bust

into one big sideways-ish dart. Then we pin the side seam closed

and pin that dart in place.

Look- we turned that into a princess seam! Which I love to infinity!

Sorry, I digressed. I have self-control problems around princess seams.

Okay, let's open out that dart and measure it.

At its widest, it's about 3" wide. Whoa. That is a BIG dart. But fear not: there is a cure!

BUST DART #2: The Underarm-and-Armhole Combination

Sometimes, one disprefers one gigantic bust dart. It looks severe, especially if the print of your fabric is, say, striped, and a big dart changes the stripe direction to something that resembles armpit chevrons. Um, no thank you.

In such cases, one might break that up into two smaller darts. These can be anywhere in the bust area, but very commonly are as follows:

One small dart is an underarm dart, originating from the side seam. To make it, pinch and pin anywhere under the armpit that you like and then close the side seam. Don't pinch all the loose fabric - leave some for the armhole (see red arrow).


The second dart is in the armhole region.

Pinch the remaining loose fabric into a dart there,

like so.

The bust area is now smooth, and the armhole is snug and non-gaping. Ignore the folds at the bust apex - as we mentioned earlier, this is only an approximate drape.

Now let's open out those two darts and size them. 

That armhole dart is about 1.5" (my ruler is slightly displaced) wide.

and the bottom one is about 1.25". Much better than the single huge 3" dart.

BUST DART #3: Shoulder Point Dart

Now we'll move away from the armhole area to create our bust darts elsewhere. 

Let's close the side seam all the way to the armpit,

localizing the loose fabric (and the accompanying ease) above the bust

and pinch the loose fabric towards the shoulder point.

We've made one gigantic dart at the shoulder point. Which, if we want, we can turn into a princess seam (here I go again!)

BUST DART #4: The Shoulder Dart

This is another bust dart that takes in the ease above the bust.

Keeping the side seam closed, let's unpick the shoulder seam. We leave the back half of the shoulder seam where it was,

and pinch the front portion

collecting all that loose fabric into an almost vertical shoulder dart.

BUST DART #5: The Demi French Dart (my own fancy name)

We've closed the shoulder seam again and have now instead unpicked more of the side seam. 

We are now going to create a bust dart below the bust.

First, we smooth the upper chest area and pin the bottom of the armscye to form the top of the new side seam (yellow arrow).

All smooth.

Then we collect all the loose fabric below the armhole into a big diagonal dart. The side seam is now a mess (yellow arrow), which is to be expected.

Pin the new side seam in place.

We now have a kind of French-dart-and-waist-dart medley. Which we could turn into a princess seam again! Okay, let's not.

BUST DART #6: The French Dart

For our finale, we're going no-holds-barred and unpicking the entire side seam

AND the waist dart. We now have only flat fabric over the front of Fleur. Totally crazy.

Smooth the upper chest and shoulder area, and drape the fabric flat around the armhole, pinning it in place.

Take all - yes, all - the loose fabric under the bust and around the waist and pinch it diagonally to the side.

And pin it. The side seam is now totally deformed and mutilated. It is a reflection of how dramatically interruptive this monster dart is.

We pin the new side seam in place as best we can (thank goodness for wide seam allowances!)

and behold our new French Dart. A real French Dart! One that combines the effects of a vertical waist dart and a bust dart.

When we open it up again to measure it, are we shocked at how mammoth it is?

This is why true French darts are usually employed by figures who are slight and slender and don't have particularly dramatic contours. Or in garments that aren't meant to fit too closely, so that they retain a fair bit of ease in the midriff area.

And we have now come to the end of our dart draping adventures.

What have we learned?
  1. Waist darts shape the hollows in the waist area, which also happens to be under the bust. Bust darts shape the hollows around the bust. They can be located anywhere around the bust - at the side, above or below. Sometimes the ones below might merge with the waist dart. 
  2. For the more well-endowed, single bust darts might be large, no matter where they are located - armhole, underarm, shoulder. So even if you rotate them and move them around, they will still be large. Bummer!
  3. Single darts can be split into two or more darts which are smaller and distort the fabric less. These multiple darts can be moved anywhere around the bust. Splitting darts is good for large darts. Hurrah.
  4. Merging darts (e.g. Case #6) results in even larger darts. Which is not a good idea if you are starting with darts that are already big. Therefore, dart merging e.g. making french darts, is better with smaller darts.

I want to point out just two more things:

One, did anyone notice the way the armholes distorted whenever we moved darts around? Even when those darts were themselves far away from the armhole? This is why techniques like dart rotation and dart shifting must be done on paper (not on an actual garment as an alteration), followed immediately by redrafting the side seams and armscyes, and even the shoulder seam (as in the case of Bust Dart #4).

Two, slopers per se are not practical for garment-sewing in that people seldom sew real garments to be as tight as their slopers (unless they're Catwoman). Therefore, practical-garment darts won't be so skintight in real life, and there will be other, prettier design elements (gathers, tucks, seams, etc.) that might take the place of darts in particular locations but still achieve their shaping effect. We will discuss these in Part III. See you then!


  1. Ohhhh, love, love, LOVE THIS!!
    Although I will never do drafting (did it for school 50 years ago) again, or have a dress form and sew for myself any time soon (attentions are on grandkids), or have much interest to learn from this "dart series", your post today changed it all!!
    I appreciate your clarity in explaining every nuances of draping for darts, progressing from one/easy/plain/obvious to another/difficult/complex/subtle ending with the dramatic French dart that I never realize existed.
    You wiped away the mysteries behind darts so a novice can understand the principles of darts construction and not be afraid of putting something together when the occasion arises. So never say never. Now I can't wait for the rest of the series.
    Such talent, such giftedness! May God continue to stoke your fire for sharing your knowledge and experience (so you don't burn out), and to give you patience for daily priorities (if I remember it right, your annual trip to Singapore is coming into focus.)

  2. This information is fantastic! Thank you so much for the time you have put into preparing the tutorial and making the complexity of darts understandable. Having these photographs as a resource will be of enormous benefit in future fitting challenges. I have read many fitting books and blogs, but nobody has come close to explaining as clearly as you! Sue.

  3. A brilliant post! As ever, your instructions are clear, concise and easy to understand and enjoyable to read. I wish I'd had you as a sewing teacher when I was first learning to dressmake. In my late twenties I attended evening classes on pattern drafting and I was then able to understand why some clothes fitted me better than others and what to do about the problem areas, and you are doing the same here but in a way that's less technical and easier to understand. Many little mental lightbulbs in your readers heads will be turned on as a result of these posts, accompanied by exclamations of " Ah! I get it now!". I take the liberty of thanking you on their behalf!

  4. Oh! Thanks so much!

  5. This is really helpful! Princess seams are my personal favorite.

  6. thanks so much - I really enjoy your tutorials - very helpful and logical!

  7. You are the best teacher for me. Thanks from spain. Kisses.

  8. My FBA also distorts the armhole (makes it higher). Do I redraft to the orginal armhole?

    1. Keira: help. I don't know what an FBA is, and what that entails. I know it's a Full Bust Adjustment, which I discovered while popping into random sewing forums. Having never done one myself, I don't know how exactly makes it higher. Do you mean "makes the armhole smaller"? i.e. does it raise the bottom edge of the armhole so the whole thing shrinks and becomes tight? If so, then yes, you need to have compensated for the armhole shrinking when slashing darts and opening darts (which is what I assume a FBA adjustment involves in some capacity). By "compensating", I mean that when you, say, are adding a 2" wide dart to accommodate for a larger bust size, you will need to have lowered the bottom of the armscye by that amount mid-draft so that by the end of the bust dart adjustment, your armhole will be the correct size and shape that you want.

      I hope this makes sense, at least conceptually. I could be totally wrong about what an FBA is, though.

  9. To me, yours is " World Class Instructuctional ". I have never seen any pattern drafting and draping SO WELL taught. I believe now, that I will finally master the art of creating well fitted garments for my family.
    Thanks a MILLION

  10. Thank you. I think I finally get it now too! I used to see the darts in patterns and just dread doing them. In the past I was just going through the motions;transferring the dart from the pattern onto my fabric, without understanding what function the dart was actually trying to accomplish. You made it simple and fun with your own little flare. The best part, are your photos! I can't even begin to tell you how many tutorials out there, post photos that leave me more confused than I was before I read the tutorial.

  11. Thank you!!! I've been altering dance costumes for years, and now some of the things I've done make sense. I've been altering by "feel" and now I know why! Thank you just isn't enough.


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