Warp End Missing And Weft Pick Missing

Definition and Overview

Warp end missing is a defect in which warp yarns running in the length direction of the fabric are missing. Weft pick missing is a defect in which weft yarns running in the width direction of the fabric are missing. Both occur due to yarn breakage during weaving, poor yarn feed, loom malfunction, or similar causes.

The missing area may involve only one yarn, or several yarns may be missing in succession. On the fabric surface, it appears as streaks, gaps, or localized thin spots, and its visibility changes depending on the weave structure, density, color, and how the light hits the fabric.

Appearance and Impact on Quality

Warp end missing tends to appear as a line along the length of the fabric, while weft pick missing tends to appear as a horizontal streak across the width. Because the density is lower than the surrounding area, sheerness and surface unevenness may appear more pronounced locally.

Since the missing area has fewer yarn intersections, it may become a starting point for snagging or tearing. It is easier to notice in lightweight, light-colored, or smooth-surfaced fabrics, and it can affect the product's appearance quality, so checking before cutting is important.

Applications and Acceptance Criteria

Warp end missing and weft pick missing are generally treated as fabric defects rather than intentional weave structures or decorative effects. Therefore, they are not terms that indicate characteristics of fabric suitable for a particular item or season.

Check the location, length, and severity of the defect, as well as whether it will appear in a visible part of the product, and determine whether it can be avoided in cutting. As a rule, areas that are noticeable or where strength reduction is a concern should be avoided, regardless of whether the item is apparel, bags, or interior applications.

Selection and Handling Notes

When receiving rolls, spread the fabric during inspection and check it not only from one direction but also at an angle. This is especially important for solid fabrics, lightweight fabrics made with fine yarns, and high-density fabrics, because streaks may become easier to see depending on lighting conditions, so it is important to standardize the inspection environment.

Washing or wetting the fabric will not restore missing yarns. Since the missing area may spread due to friction during washing or snagging during wear, do not place sections containing the defect in areas of the product that will be under stress.

In sewing, if a seam or slit is placed near a missing area, the fabric may become unstable. If use is unavoidable, confirm in advance whether it can be contained within the seam allowance or whether reinforcement is possible according to the specifications.

• Record the defect location before cutting and avoid it by marking.
• Check whether the same defect is present in both samples and mass production.
• Share defect criteria according to the inspection standards with the business partner.

Differences from Similar Terms

Warp and weft are the names of the directions that make up woven fabric, and warp end missing and weft pick missing refer to the state in which those respective yarns are missing. These should be distinguished from explanations of warp and weft themselves.

Yarn irregularity and horizontal barre are phenomena that appear as streaks due to differences in yarn thickness, dyeing, tension, and similar factors, and they differ from warp end missing and weft pick missing, in which the yarn is physically missing. In addition, fabric defects is a general term for defects and appearance issues including these.

Frequently Asked Questions