Fabric Terminology

Yarn

Continuous strands used in making fabric.

Grain

Refers to the direction of yarns from which fabric is woven. Should be at right angles to each other (on-grain). If one or both threads are on a slant the fabric is off-grain.

Lengthwise Grainline

Runs parallel to the selvage (Warp Yarn).

Crosswise Grainline

Runs selvage to selvage (Weft Yarn).

Selvage

Firmly woven finished edge of fabric (the edge does not fray).

Raw Edge

Either torn or cut edge of fabric – may be lengthwise or crosswise.

Bias

Any line that does not follow the threads of the fabric – has some stretch.

True Bias

Diagonal edge that occurs when the fabric is folded with the crosswise grain running in the same direction as the lengthwise grain.

Woven Fabric

The interlacing of yarns.

Knit Fabric

The interlooping of yarns.

Prints and Patterns

Fabric might be woven with a pattern, or printed with a design.

The main difference between a pattern being woven as the fabric is constructed, or printed onto the surface of the fabric is that generally anything printed onto the fabric might not be straight in line with either the lengthwise or crosswise grainline.

Stripes are a great example of this.  Stripes that are part of a fabric’s construction tend to be straight (unless the fabric has been pulled off grain), while a stripe printed tends to end up on a slight angle.  If you are creating a garment with a printed stripe fabric you then have to make a decision to follow the printed stripes, or to follow the grainline of the fabric.  To help you make this decision, consider how the overall finished garment will look.  If you opt to follow the grainline of the fabric, will things look a bit ‘off’ if the stripes aren’t straight?

When working with a printed fabric you might also consider the direction of the print.  Is there a direction?  If there is a direction to the print ensure that there is some extra fabric accounted for when laying out the pattern pieces.  If the direction of the print (or fabric texture, which is called nap) isn’t super obvious when working up close with the fabric draw yourself some directional arrows along the fabric selvage to give yourself reminders of the direction that you should be placing your pattern pieces.