Sewing 303 - Pattern Drafting: Basic Dart Manipulation

Updated: Apr 26

Welcome back, dear readers. Today, I will introduce the technique of dart manipulation or simply put, changing the positions of the darts. The position of the darts on the basic slopers can be considered starting points, they are simply at that position because that is where they are needed the most for that particular design.


Where and how you position a dart depends on the design of the garment and sometimes darts are not even functional, just merely decorative. I have mentioned previously in Sewing 202, that the main function of a dart is to create shape by blending a bigger area into a smaller area, which causes the flat pattern to become a three-dimensional shape. Darts can also be turned into seams, pleats, gathers, tucks and so on to create fullness and other looks.


Tools you will need

1. Straight ruler

2. Pin or Awl

3. Pencils / Eraser /Sharpener

4. Sellotape or Gum

You may have seen this diagram on the internet or in books at some point which shows the classic positions to swivel the dart. We are not repeating all that in this topic, rather I will concentrate on the 2 main techniques for moving darts.


1) Slash and spread method

A) Draw a line from the apex to the point that you want to move the dart (point A) Cut through this line to the apex.

B) Cut through the dart leg to the apex (point B), leaving a little connection so that the cut piece is still attached.

C) Move point B to meet Point C and tape it close. Now the whole dart has been moved.



2) Pivot method

A) Mark the point that you want to move the dart (point B) .

B) Holding the pattern in place, trace around it from point A until you get to point B. Mark it.

C) Place a Pin or Awl at the apex and pivot the pattern to the right until point C touches point A, closing the first dart.

D) Still holding the pattern in place, trace from the point previously marked as B (now D) to point C, completing the block.

E) Join points B and D to the apex to complete the new dart.

The above examples feature moving the position of only one dart, but they can also be used to open up multiple darts in different positions at the same time. We will cover that another day.


Things to remember

1) This is flat pattern drafting, therefore the pattern must always remain flat, if there are any folds or points, then something is wrong.

2) All darts must pass through the apex of the bust, regardless of the shape or number of the dart

3) When sewing, it is usually preferable not to sew the dart right from the apex, as this will create a pointy look unless that is the look you are going for. It is best to move the dart point down an inch or two instead.

4) A dart can be spread out very wide to add pleats, ruching, gathers or even more darts.


That's all for the basics of dart manipulation. We will expand on this in another tutorial. Thanks for reading. Please let me know how it works out for you.