Weaving Adjustment
Mechanical weaving adjustments control the rate at which the newly formed fabric is pulled away from the fell of the cloth. The loom take-up determines the number of picks per inch and the overall density of the woven material. Precise calibration ensures that the fabric construction matches the technical specification for weight and width.
Gear Configuration
Tension management relies on a series of gears or an electronic motor that rotates the take-up roller. In a mechanical loom take-up, the operator changes the pick wheel to alter the distance the fabric moves after each insertion of the weft yarn. Modern air jet and rapier looms use computerized sensors to adjust the movement in real time.
Quality Defect
Irregularities in the movement of the roller cause visible faults known as set marks or starting marks. If the loom take-up slips or pauses, the pick density becomes inconsistent and creates a thick or thin band across the width of the fabric. These defects are often permanent and lead to the rejection of the entire roll during final inspection.
Material Contraction
Shrinkage calculations must account for the difference between the length of the fabric on the loom and its length after it is relaxed. As the tension from the loom take-up is released, the yarns contract and the pick count increases slightly. Designers specify the on loom density to achieve a specific finished weight after the fabric is scoured and dried.
