You may be familiar with darts as those pointy things you throw at a dartboard on the wall of your favorite pub. Although they don’t fly, darts in sewing are still vital components of the overall sewn project. For the most part, sewing darts look quite similar to their gaming counterpart. They are wide on one end and pointy on the other. Pub darts are all about a smooth trajectory and pinpoint accuracy. Sewing darts are also big on smooth lines and precise points, but their function is all about shape. No matter what kind of sewing you do, sooner or later, you will likely have to sew a dart. Throwing darts… you can do on your own time.

Why we need darts

All fabric is flat, but you already knew that part. What you may not know is darts are how flat fabric is shaped to the contours of the body. This is why darts are most prevalent in garment sewing.

When a garment is initially designed, it starts as a two-dimensional drawing. The drawing is then translated into flat pieces of muslin. These muslin pieces are draped on a mannequin to bring the drawing to 3-D life.

The pieces of fabric are cut to the measurements of the mannequin, with seam allowance and ease (room between the body and garment) added in, to create the overall style of the garment. As the pieces are shaped to the mannequin, there are specific body contour areas where excess folds of fabric always occur: the shoulders, bust, waist and hips in particular. It’s in these areas where darts are created. Once the draping process is completed, the pieces are removed from the mannequin, “trued up” (straightened and cut into their final shape), then used to cut the actual garment fabric to continue the pattern manufacturing process.

One interesting fact is that although nearly all garment designs have darts in the draping process, those darts may not be part of the final design. For example, if a knit fabric is going to be used, when the pieces are removed from the mannequin, the darts formed during the draping process are left in place when the final fabric is cut. The stretch of the knit fabric is often enough to give the shape needed around the body contour areas.

But in the majority of situations, darts are part of the garment, and are sewn as mirror images to one another on either side of the garment. Of course, the standard caveats apply: rules can change depending on the style, the fabric being used, and/or the overall design.

In addition, when fitting a garment to a specific person, you can alter the size (width and length) of the dart or add more darts as needed for a perfect fit. Darts are very important, very handy little pointy things!

Even in the Sew4Home studio, where we don’t regularly delve into garment sewing, we still have the need for darts. When you need to slightly alter the shape of something, a dart is usually the answer!

We created our Dead Roses Halloween Witches Hat with darts on the brim to add shape. We’ve also experimented with darts to shape the bodice of several of our aprons or along the corners of a more rounded purse or tote bag, such as our Heart & Ruffle Apron, Soup Bowl Cozies, and Zippered Travel Pouch.

Below is our step-by-step overview of the different types of darts, along with the best ways to mark, sew, and press them.

Types of darts

As we stated above, a basic dart is shaped like a point. It’s wide at one end and narrow at the other. You’ll see these along a seam line where added shape is needed. They can be straight or curved.

Below is a definition list of the types of darts you are likely to see in various garment styles. We went through our pattern drawer in the Sew4Home studio to grab some examples of what these look like on a commercial pattern. Unfortunately, we didn’t find an example of some of the less common ones, but most are self-explanatory from their names. Depending on the style and sewing level of the garment, some darts will be simple to understand, while others are more complex. The one thing they have in common is points. There are always two at the wide part of the “V” and one at the end point of the “V”. Sometimes there is also a set of points mid-way through the “V”, and sometimes there’s a line down the middle.

Waist darts

This kind of dart speaks for itself. You most likely own a garment with this type of dart. It brings in the shape of the garment from the waist to the hip. Below is a pant pattern with waist darts.

Bust darts

Let’s see… where might these be found? They start under the arm at the side seam and point toward the fullest part of the bust. Sometimes, on very fitted garments, you’ll see these used in conjunction with another set of bust darts that go from the waist to just underneath the bust. The example below is from a dress with two sets of bust darts.

French darts

This type of dart is used in place of bust darts. It’s one long dart, beginning at the bust and curving down to the side seam. Since these are so long and/or wide, usually a portion of the fabric is cut away to reduce bulk.

Elbow darts

Darts created at the elbow are usually seen in elaborately styled sleeves or fitted sleeves made of two pieces. Sometimes, you want the shape of the sleeve to be very fitted, but the elbow still needs room to move. Therefore, one, two or three small darts are sewn from the sleeve underarm seam to the elbow point.

Dart tucks

Contrary to all the others in this list, these are not sewn in the shape of a point. Instead they’re sewn straight for a set length. These are really only used along the waistline. In our Patio Party Groovy Hostess Apron, we used dart tucks to shape the top of our apron piece (which was otherwise a basic rectangle) where we attached the band and tie.

Contour darts

Again, slightly contrary to the rest of the crowd, these darts are shaped as a diamond. You’ll see contour darts used on longer garment styles, like a tunic, jacket or dress. They can be sewn on the front and/or the back. Since they are diamond-shaped, they add shape at the bust, waist and hips all at once. The pattern piece below is the back of a jacket, where contour darts are used to add shape at the back waistline.

We wanted to show you an example of a complex pattern that is considered more advanced. Here we see shoulder darts, which are curved, a really long bust dart, and a contour dart. Not to mention this pattern has 12 sizes on one pattern piece! This is either a very complex pattern or a topographic map of Arizona.

Ways to mark a dart

Darts are made in a mirror image to one another: matching darts on the left and right side of a garment or identical darts on the front and the back. If the mirrored darts are not sewn precisely, you’ll notice it when your project has a wonky or off-balance finish.

The best way to end up with successfully sewn darts is to start with careful marking. Mark your pattern pieces on the wrong side of the fabric after you’ve cut them out.

The marking tool you select is a matter of personal choice. We always recommended testing any fabric pen, pencil or chalk on scraps. If your fabric is a light color, you may see marks bleed through in the seam of the dart.

Below is a collection of some of the marking tools we have in the Sew4Home studio. The one you select will determine how you actually mark the points of the dart.  For example, if you use a tracing wheel and transfer paper, your process for marking the dart will be slightly different than the tailor’s chalk we selected.

You may be wondering why there’s a spool of thread in the picture. It’s for the marking option known as “tailor’s tacks.” This is a couture technique used by the finest seamstresses and tailors. It’s very effective, but does take time to do. We don’t have the space here to go into great detail on this specialized technique. To learn more about tailor’s tacks, check out a general sewing book, or look for information on the Internet.

The majority of the time, you cut pattern pieces with the fabric right sides together. This means you need to mark darts on both pieces (right and left). But, one of the pieces you need to mark is under your pattern piece, and you can’t move it because you need it to know where to mark the dart. And, the other piece is underneath the first piece, and you don’t want to move the fabric too much to mark that one because it could easily skew the dart position.  HEYYYYYYY!!! Don’t worry; here’s what to do.

Pinning, lifting and marking – the standard marking process

1. With your fabric right sides together, and the pattern firmly pinned in place, cut out your piece.
   NOTE: You may have to other markings on the pattern, depending on what you’re making. Here, we are only focusing on the darts.
2. Place pins through the indicated dart points on your pattern. This keeps you from having to move the pattern pieces too much.
   NOTE: It’s often also recommended to make small snips (with scissors) in the fabric at the top of each side of the dart. This is especially necessary if, for some reason, you are unable to mark your fabric with a marking tool. Since we are marking our fabric, we did not clip the dart at the top in our example.
   
3. Gently fold over your piece onto itself (with the pattern still pinned in place). Fold to just beyond the end to the dart, exposing the underside with the marking pins sticking through.
4. With the fabric marking tool of choice, (we used tailor’s chalk), make a small mark where each pin comes through underneath.
   
5. Gently unfold the fabric piece back into place.
6. Remove the pins holding the paper pattern in place on either side of the top of the dart.
7. Pull back the paper pattern gently to expose the pins along the top of the piece. Mark these dart points.
   
8. Remove the pins at the top of the dart and any additional pins to expose the bottom point of the dart. Mark this bottom point where the dart ends.
9. When these three points are in place on both the top and bottom layers of fabric, completely remove the entire paper pattern. You’ll now be able to see each set of points marked for each dart.
10. Using a ruler and your fabric marking tool, simply connect the dots on either side of the dart.
    
    
    NOTE: As you become more advanced with this technique, you may find you can successfully sew darts using just the marked points and a pin or two.

Other marking options

This is the most common, but not the only way to mark a dart. Alternative techniques use the other marking tools pictured above. Some people (S4H included) prefer to only use pins. Using small head pins, you pull the pins through the paper pattern to expose the marked points. You can then use these pulled-through pins to secure the dart in place for sewing, without ever removing the pins from the fabric. Like tailor’s tacks, this is a more advanced approach. Often, the method you end up choosing will depend on the type of fabric(s) you’re using. Hey…. that rhymes!

Stitching darts

Below, we show you how to sew a basic dart and a contour dart; these are the types you’ll see most often. We used light colored fabric and dark thread so you could clearly understand the technique. When you actually sew darts, you should use a thread that best matches your fabric color. In addition, we used only two pins to hold the dart in place, you will most likely want to use a couple more on your first try. But remember, don’t sew over pins.

NOTE: Depending on the fabric, sometimes it’s helpful to press the dart before sewing to help maintain its shape. However, if the dart is curved, it’s best to simply mark the curve and sew on the line.

Basic dart

1. Fold the dart in half, right sides together, matching the marked lines.
2. Place pins in dart, making sure the marked lines are matched up perfectly. You can check this by watching where the pin comes through on the other side.
   
3. Place the top of the dart under your machine foot (the wider end). Use the marked line to position the fabric so you will be sewing straight.
   
4. The most important part of a successful dart is SEWING OFF the fabric at the precise bottom point of the dart.
5. Sew slowly along your drawn line, using a straight stitch. You can backstitch at the top, but since you will often be sewing the dart into a waistband, facing or another seam, you don’t have to backstitch.
   NOTE: Depending on the type of fabric you’re sewing, you may need to adjust your stitch length. Some experts recommend shortening the stitch as you sew toward the point to help keep the dart secured.
6. As you approach the point, plan to sew completely off the fold. This will seem odd at first.  Remember, if you have to, you can rip out the seam.
   
   NOTE: We’re lucky enough to have Janome sewing machines in the S4H studio. Some of them have a lower thread cutter, which is a fantastic feature to use, EXCEPT when sewing a dart. If you have a similar feature on your machine do not use it; you need to leave a long thread tail at the point of each dart.
   
7. At the bottom of dart, you NEVER backstitch. The thread tail is hand-knotted to secure it in place. You can use the tip of a seam ripper or a straight pin to help you gently separate the twisted threads so they can be easily knotted.
   
   NOTE: Interestingly enough, we found out that darts are rarely knotted in ready-to-wear because it’s too time consuming. Manufacturers simply leave the twisted threads hanging. For the most part, this works, but if you’ve ever had a dart “let go” on a store-bought garment, now you know why.
8. Once you are done with one dart, sew its twin. The goal is to sew the darts exactly the same. It’s good practice to never take a break between sewing darts (or any other mirror-imaged sewing tasks). You’re much more likely to sew two identical darts back-to-back than if you take a coffee break in between.
   

Contour dart

1. Cut out your pattern piece, and mark the dart in the same manner as for the basic dart.
2. Fold the dart, right sides together, and pin in place. As above, you want to be super careful to match the the drawn lines on both sides.
3. Here’s where a contour dart differs from the basic dart: you start and end your stitching line at the fold of the fabric and pivot in the middle. Since the top and bottom of the dart are the same in this example, you can start at either end of the dart.
4. Place the fabric under the foot to sew from the first point to the pivot point.
5. Using a straight stitch, being sewing from the point along the drawn line. For this dart, you need a long thread tail at the beginning and the end to knot securely. Do not backstitch.
6. Stop at the center pivot point with the needle in the down position.
   
7. Raise the presser foot and angle the fabric to sew to the end point. You want to sew off the edge of the fold in the same manner as the basic dart.
   
8. And, here’s the finished product
   
9. Sew the mirror-image contour dart so it’s the exact same length and width as your first one.
10. Below is a picture of our test sample. There’s a center back seam and a contour dart to either side. See how the two matching contour darts bring in the waist at the back?
    

How to press darts

The direction in which you press darts is important. You do not want them interfering with the look of your finished project, so you need to press them to the shape of the body. Therefore, always press darts in the opposite direction to the shape. For a vertical dart, like a waist or contour dart, you press it toward the side seam. For a somewhat horizontal dart, like a bust dart, you press it down toward the waist.

In order to properly press a dart, it’s really best to use a pressing ham. Now that your flat fabric piece has a shape, you don’t want to flatten it out again!

Darts using thick fabrics

We want to at least touch on the topic of sewing darts on thick fabrics. You mark and sew them using the same techniques as we’ve described above. But when sewing, you will likely need a slightly longer stitch. The only real issue with darts in a thick fabric, is just that, it’s really thick! Once the darts are sewn, before pressing, use scissors to cut the dart open.

You’ll know when to stop clipping because your scissors will only fit so far into the point. Now you can press the dart open, and more importantly, flat. Without this extra step, you’re likely to have big lumps in your garment wherever the darts may be.

NOTE: In our example above, we simply cut open our sample dart to show you how it would look. We did not use an actual thick fabric.

Sewing darts evenly and accurately each time simply takes practice, practice, practice. Before you know it, darts will be second nature, and you’ll be shapin’ and curvin’ like a pro!

Sample Creation and Instructional Outline: Jodi Kelly