Sewing Pattern Symbols and Markings

What you take from this lesson: Learn to read any pattern without having to ask what each mark means.

The grainline arrow

It is the most important mark and the one most often ignored. The arrow means the piece has to be placed on the fabric parallel to the selvage, that is, following the warp yarns.

Fabric does not behave the same in every direction: lengthwise it barely gives, crosswise it gives a little, and on the diagonal it gives a lot. If a piece is placed turned to make better use of the fabric, that piece will stretch differently from the rest of the garment. The typical result is a t-shirt that, after two washes, ends up with a twisted side seam.

Notches

They are short marks perpendicular to the edge. They serve one purpose, and it is one that saves a great deal of time: showing which point on one piece lines up with which point on the other.

When a sleeve is sewn in, the length of the sleeve cap and the length of the armhole are similar but not identical, and the sleeve cap almost always has a little extra fullness that gets eased in. Without notches you have to adjust by eye, and the sleeve ends up twisted. With notches, you match the marks, pin the pieces together, and the excess spreads out on its own.

The fold line

When a piece is symmetrical—a front with no opening, for example—it is not drawn whole: only half is drawn, and the pattern shows that this edge goes against the fold of the fabric.

You can recognize it because the edge carries a line with two arrows pointing toward it, or simply the words “on fold” or “fold.” That edge is never cut: if you cut it, the garment comes out split down the middle.

Darts, pockets, and other internal marks

Inside the outline there are marks that are not edges but work instructions:

• Darts: elongated triangles that are sewn closed to shape the garment to the body. They are marked with dots or small holes at the corners.
• Pocket placement: a rectangle or a few crosses that show where the pocket sits.
• Hem fold line: shows how far the bottom of the garment is folded up.
• Buttons and buttonholes: circles and short lines on the front facing.

The test square

Digital patterns also have a mark that does not exist on paper ones: a square with its measurement written next to it, usually on the first page.

It is not part of the garment. It is there to verify that the print came out at the correct scale: you measure it with a ruler, and if it measures what it says, the whole pattern is right. It is the cheapest check in the entire production run.

Common mistakes

• Cutting the edge marked “on fold”: the piece comes out split in two and there is no way to recover it.
• Skipping the notches to go faster, and then spending twice as long getting the sleeve to sit right.
• Mistaking the grainline arrow for an “up” indicator: the grainline marks direction, not orientation.

In short

The grainline arrow says how to place the piece, notches say where to join, the fold line says which edge not to cut, and the test square says whether the print can be trusted.