Correlating Loom Sett and Machine Gauge to Wet Processing Shrinkage
Correlating loom sett and machine gauge to wet shrinkage requires matching grey thread density and stitch length to wet relaxation limits before finishing.
Wales per Inch
Distribution Pattern
Distribution pattern measuring the number of vertical columns of loops per inch across the width of a knitted fabric to determine horizontal stitch density and width. Calculation of wales per inch is a primary task for quality inspectors, as it indicates the tightness of the knit and the proper functioning of the needle bed. This value is determined by the spacing of the needles on the machine, but it can be altered during the finishing process through the application of widthwise tension.
When the number of wales per inch increases, the fabric becomes narrower and more compact, while a decrease indicates a wider, more open structure. The boundary of this measurement is the physical width of the fabric, as it is only valid when measured perpendicular to the direction of knitting.
Counting Method
Precision in recording this value involves the use of a magnifying pick glass to identify and count each vertical column within a one-inch space. The measurement must be taken at several points across the width of the fabric roll to ensure that the density is uniform from the left to the right side. If the number of wales per inch varies significantly across the web, it suggests that the fabric has been stretched unevenly in the stenter or that the machine gauge is not consistent.
This count is a critical component in the calculation of fabric weight, as it determines how many yarns are present in a given horizontal area. In the garment factory, the cutting team uses this data to verify that the fabric meets the specifications for the marker. If the wales per inch count is too high, the fabric will be too narrow, and the pattern pieces may not fit on the roll, leading to excessive waste.
Conversely, if the count is too low, the fabric will be too wide and may have a loose, unstable hand. This metric is also used to monitor for spirality, as a shift in the angle of the wales can indicate that the fabric is twisting. Consistent measurement ensures that the final garment has the correct dimensions and a stable appearance.
The measurement should be taken after the fabric has reached a state of equilibrium to avoid errors caused by temporary tensions.
Structural Stability
Influence of this count on the performance of the textile includes its resistance to horizontal stretching and its ability to maintain a straight grain. A higher number of wales per inch generally results in a more stable fabric that is less likely to bag or lose its shape during wear. This is particularly important for structured knit garments like polo shirts and high-end knitwear.
Finishing Impact
Final values for this metric are often set during the drying and heat-setting stages where the width of the fabric is permanently fixed. If the mill attempts to pull the fabric too wide to increase yield, the wales per inch count will drop, and the fabric will have high residual shrinkage. Quality standards always specify the target count to prevent this practice.
How Woven and Knitted Fabrics Are Built
Fabric performance depends on greige interlacing geometry, wet processing relaxation, and multi-mill supply chain lead times.