In circular knitting production, fabric defects directly lead to rejected textile batches, wasted yarn, higher operating costs, and delayed client delivery schedules. For textile factory owners, knitting technicians, and quality control supervisors, rapidly diagnosing the root causes of fabric flaws—whether in EASTINO Circular Knitting Machines or high-speed jersey production lines—is critical to maintaining mill profitability.
Most common knitted fabric defects stem from minor mechanical misalignments, improper yarn tension, or worn knitting needles . This technical guide outlines the 6 most frequent knitting defects, their mechanical root causes, and practical preventative adjustments to ensure flawless fabric quality.
1. Fabric Holes or Drops (Busted Loops)
Fabric holes occur when the yarn breaks or bursts during the loop-forming cycle. If the yarn drop-off depth at the knock-over point is too severe, excessive tension causes the yarn to snap, resulting in visible holes.
Primary Causes:
Misadjusted yarn feeder position.
Weak points or slubs in the yarn that snap under loop tension.
Uncut yarn knots passing through ceramic guides.
Excessive yarn feeding tension.
Improper stitch cam adjustment subjecting yarn to extreme strain.
2. Drop Stitches (Vertical Laddering)
Drop stitches present as vertical laddering or missing loops along the wale direction. This flaw is typically caused by defective knitting needles or improper yarn feeding where the latch fails to catch the yarn.
Primary Causes:
Misaligned yarn feeders or incorrect feeder height.
Incorrect yarn threading path.
Improper fabric take-down tension.
Overly dry yarn or raw materials lacking adequate wax lubrication.
Insufficient yarn tension causing loop escape.
3. Continuous Unroving (Multiple Loop Escapes)
Unlike an isolated drop stitch, continuous unroving occurs when a sequence of consecutive loops escapes along the course. When yarn snaps and goes undetected, subsequent needles continue cycling without catching yarn, resulting in widespread structural tearing.
Primary Causes:
Yarn Breakage: Sudden yarn snapping during high-speed knitting.
Unnoticed Machine Cycling: Needles continue cycling with closed latches without receiving new yarn.
Sequential Loop Release: Subsequent loops lose yarn support and unrove along the wale/course, causing large open gaps.
4. Tuck Stitches or Double Loops
Double loops occur when a previous loop fails to clear the needle latch during the knock-over phase, causing an unintended second loop to stack on the same hook. This creates irregular raised knots or distorted fabric texture.
Primary Causes:
Inadequate yarn waxing leading to high friction against machine parts.
Insufficient needle clearing height, preventing the old loop from dropping below the latch.
Incorrect fabric take-down or roller tension.
Misconfigured stitch cams or damaged sinker & cam spare parts .
5. Snagging & Filament Fuzzing (Mechanical Abrasion)
Snagging and surface fuzzing occur almost exclusively on continuous filament yarns (such as polyester, nylon, or spandex blends). Sensitive filament fibers tear or catch when contacting rough metallic surfaces along the yarn path.
Prevention & Inspection Checklist:
Inspect ceramic yarn guides for burrs, cracks, or rough wear.
Check cylinder needles, latches, and hooks for scratches or deformations.
Inspect take-down roller surfaces for sharp edges or abrasive build-up.
Ensure proper fabric roll handling and storage to prevent post-knitting friction.
6. Loop Riding & Horizontal Slub Knots
Loop riding manifests as horizontal, rope-like knot clusters or irregular fabric bunching running across the fabric width. This defect is heavily tied to imperfections in the fabric take-down mechanism or yarn slubs.
Primary Causes:
Un-even thick slubs or thick spots in the supply yarn.
Insufficient or unstable take-down roller tension, allowing loops to ride up the cylinder.
Localized loop accumulation and course contraction across the width.
Summary Troubleshooting Matrix for Knitting Factory Operators
| Fabric Defect | Primary Machine Component to Check | Recommended Technical Action |
| Fabric Holes / Drops | Stitch Cams & Feeder Eyelets | Adjust feeder height; lower stitch cam tension; inspect yarn knots. |
| Drop Stitches | Latch Needles & Feeder Centering | Align yarn feeders; replace bent latches; increase take-down pull. |
| Continuous Unroving | Yarn Stop-Motion Sensors | Calibrate optical stop-motion sensitivity; inspect yarn creel paths. |
| Double Loops / Tuck | Needle Raising Cams & Waxing | Increase needle clearing height; apply paraffin waxing to yarn; adjust cams. |
| Snagging / Fuzzing | Ceramic Eyelets & Needle Hooks | Polish or replace worn ceramic guides; replace burred cylinder needles. |
| Loop Riding | Take-Down System & Yarn Quality | Tighten take-down roller tension; filter out thick yarn slubs. |
Upgrade Your Textile Mill Efficiency with EASTINO Technology
Preventing fabric defects starts with precision-engineered machinery and high-durability replacement parts. At EASTINO, we design high-performance EASTINO Circular Knitting Machines , OEM-grade Knitting Needles , and hardened Sinker & Cam Spare Parts engineered for zero-defect fabric output.
Experiencing persistent fabric defects or looking to upgrade your factory’s knitting output? Contact EASTINO’s technical export team today for technical consultation, machine tuning guides, or a fast quotation on genuine spare parts!
Post time: Oct-21-2026