- Lengthwise grain refers to the threads in fabric which run the length of the fabric, parallel to the selvedge of the fabric.
- Crosswise grain are the threads that run perpendicular to the selvedge of the fabric or the cut edge of the fabric as it comes off the bolt.
- Bias grainis the thread line that is at a forty five degree angle to the lengthwise and crosswise grain of the fabric as it is on the bolt. The bias has stretch in woven fabric and will hang differently than a garment that has been cut on the straight or crosswise grain.
The Bias grain however will stretch, making the bias grain a perfect for couture areas such as covering cording to create your own piping.
Because the bias grain does react differently that the lengthwise or crosswise grain it may require special handling. For example; A skirt cut on the bias grain must hang for 24 hours before you attempt to hem it.
Although knit fabrics stretch, the amount of stretch may vary in the different grain lines.
Always read the back of a pattern envelope that is designed for knits and test the stretchability of the fabric with the information on the pattern envelope.