What does cut on the grainline mean? Learn the difference on fabric between the lengthwise grain, the crosswise grain and the bias

It’s back to school time again and we’re sharing a series of posts all about basic sewing concepts. These are very important for all of you who are just beginning. Today, in particular, we want to explain to you about a term that you will come across on many occasions when you’re going to make up any pattern: Cut on the grainline. With sewing, as with any other hobbies, there’s a specific vocabulary that applies to certain techniques and materials. And it’s very important to know what these terms mean beforehand.

grainline sewing patterns

Cut on the grainline

All fabrics have a determined width and you can buy the length required for each project. In our case Katia Fabrics are 59” (150 cm) wide. In our online shop you can see that the minimum length available for sale is 19 5/8” (50 cm). For longer lengths add multiples of 3 7/8” (10 cm).

grainline fabrics requirement

Each edge that defines the fabric width is called the selvedge. Each selvedge is different depending on the fabric: frayed, different colour, with text etc. On our Katia Fabrics you will always find the logo printed on one of the selvedge edges.

grainline selvages

All fabrics have three different thread directions: vertical or the warp, horizontal or the weft and diagonal or the bias.

Correctly positioning and cutting out pattern pieces on the grain is something that should be learn when starting out so that the optimum appearance and correct hang of the garment is achieved. On our pattern pieces you will find a double arrow that indicates the direction of the grain and must be placed parallel to the selvedge (unless otherwise stated).

grainline, croossline and bias

WARP

The warp threads are the vertical threads that run parallel to the selvedge. The majority of garments are cut on the warp because the fabric does not stretch in this direction which ensures that the hang of the garment is correct. In fact, if you pull two points close to each other along the warp threads you will see that the fabric does not stretch and it stays rigid. This is with the exception of jersey and elastic fabrics of course.

Tip: If the fabric has a raised surface like velvet, corduroy or a synthetic fur type fabric, always cut from top to bottom going with the direction of the nap or furry surface. If you pass your hand over the fabric and it stays flat and smooth this is the correct direction of the warp.

WEFT

The weft threads are the ones that run horizontally from one selvedge to the other. They are perpendicular to the weft threads.

Some garments or garment pieces are cut on the weft. When matching a print design or to avoid certain areas becoming deformed. Blouse yokes can also be cut on the weft. If you pull two points close to each other along the weft threads you will see that the fabric gives slightly.

BIAS

The diagonal direction that is at a 45º angle with the selvedge is known as the Bias. Cutting on the bias creates a lot of elasticity and gives a spectacular drape to garments. Like, for example, the typical flared skirts from the 1950s.

If you pull two points close to each other along the bias you will see that the fabric stretches a lot.

Thanks to its elasticity the bias is perfect for cutting strips of fabric that can be used for finishing off necklines and armholes.

TIP: It is very important to identify the fabric grainline because it is going to determine how you position the pattern pieces on the fabric correctly.

grainline of the sewing patterns