Moving a dart

Fabric is flat and the bust is round. For the front to follow the figure, the extra fabric above the bust is taken out with a dart. On the Müller dress block that the generator drafts, the bust dart comes from the shoulder. But it can be moved to the side, the waist or the neckline, and one block you have already fitted becomes a blouse, a dress with a waist seam or a gathered bodice. Nothing has to be drafted again.

The intake depends on the figure and must not change. Where the dart comes from is a design decision. Moving a dart transfers the same intake to another edge.

The main rule

A dart always points at the bust point — the most prominent point of the bust. So the slash line — the line you cut along to move a dart — always runs to the bust point. The other end of the dart, on the edge, can be anywhere: the design chooses it.

A dart aimed past the bust point does not shape the bust; it only makes a fold.

Where a dart can go

• A, to the side seam — the most common choice. A side dart is hardly noticeable.
• B, to the waist — for dresses with a waist seam. Not for a large bust: the intake becomes so wide that its point cannot be pressed out neatly.
• C, to the centre front — rarely kept as a dart here; the intake usually becomes gathers or pleats.
• D, to the neckline — seldom sewn as a dart. More often it is parked here temporarily to free the shoulder, before drafting a kimono sleeve, for example.
• E, to the armhole — found, for example, in corset bodices.

How to move it: the slash method

Let’s move the dart from the shoulder to the side seam.

1. Mark the bust point on the copy of the block — it is the point of the shoulder dart.
2. Draw the slash line. Choose a point on the side seam and join it to the bust point with a straight line.

3. Cut along the line from the side seam to the bust point, but not right through the bust point: leave the paper joined there so it works as a hinge.
4. Close the old dart. Bring the legs of the shoulder dart edge to edge and tape them. Part of the front turns about the bust point, and a new intake opens at the side — exactly the same amount.
5. Slip a piece of paper under the opening and tape it down.

6. Shorten the dart. Its point stops 1–2 cm short of the bust point: a dart sewn right up to the point makes a sharp cone instead of a soft bust shape.
7. True the edge. Fold the new dart the way it will be stitched and correct the side seam so that it runs smoothly.

Done: the same block, with the dart now at the side.

Without cutting: the pivot method

The same transfer can be done by pivoting the pattern piece around the bust point:

1. Lay the front pattern piece on a clean sheet and trace the part that stays in place (in our example, the larger part, with the centre front and the neckline): from one leg of the old dart to the new line. Mark the bust point.
2. Hold the piece down at the bust point (with a pin or a finger) and turn it until the other leg of the old dart lands on the first one.
3. Trace the rest of the front. The intake ends up where the new line runs.

This way any dart can go to any edge. In software such as Olcroy the rotation tool does the same: the centre of rotation is the bust point, the angle is the intake of the old dart.

A dart for stripes

On striped or checked fabric a side dart must run exactly horizontal, or the stripes will not match once it is stitched. On plain fabric a side dart can slant.

How to find the horizontal line

1. Find the midpoint of the shoulder dart’s intake and draw the dart’s centre line from there to the bust point.
2. Put the right angle of a set square on the bust point with one side along the centre line.
3. The new line runs along the other side of the set square.

Check yourself

• Every line was drawn to the bust point.
• The new dart is shortened by 1–2 cm and stops short of the bust point.
• The legs of the new dart are equal in length.
• Edges that are sewn together match in length. After the transfer, fold the dart and compare, for example, the front side seam with the back side seam.