Example.—Find the length of warp required to weave a piece of 5-stave satin 94 yards long (36 inches to the yard), 94 reed, 180 picks per inch, 60’s twist, 70’s weft.
The number of intersections per inch will be two-fifths of the number of picks, as the warp intersects twice every five picks or pattern.
∴180 × ⅖
= 72 intersections per inch;
and
72 × 470’s counts
= 4 per cent. contraction.
The length of warp required to weave the 94 yards piece would therefore, roughly, be 98 yards.
In a plain cloth the contraction is much more than in a satin, and the percentage is greater in heavily picked cloths than light ones.
In a plain cloth of, say, 120 picks per inch, 60’s twist, 70’s weft, the percentage of take-up will roughly be as follows:—