Читать книгу The Quilter's Bible - Linda - Страница 37

Fabrics are made with lengthwise threads called warp threads and crosswise threads called weft threads. Warp threads are on the straight grain and are the strongest with the least stretch. Weft threads are also firm but with a little more give. At a 45 degree angle to these threads is the bias grain, which has the least strength and the most stretch (see diagram).

Cutting and sewing fabric on the straight grain causes the least stretching and distortion, which means that patches and units will align more accurately. When edges are on the bias they are likely to distort and stretch with handling and pressing, so when in doubt have the straight grain on the edges.

A fabric’s tendency to stretch can be a positive benefit in some cases, for example, when cutting strips for bias-strip appliqué and bias binding, when you want the fabric to ease around curves easily. Bias-cut edges can also be of benefit for needle-turn appliqué, where edges need to be turned under smoothly. Bias-cut edges are also useful for slashing and chenilling to encourage fabric to fray and ‘bloom’.