Different Types of Fabric Defects with Pictures

You pull a fresh roll of fabric off the cutting table, only to spot a faint diagonal streak running through the grain—barely visible at first, but once you see it, you can’t unsee it. That’s how most defects sneak up on you: subtle at first, then suddenly critical when they show up in a finished garment.

Fabric Defect

There are countless fabric defects that emerge during weaving, knitting, and even earlier—from yarn inconsistencies all the way through finishing. Since fabric forms the foundation of every apparel item, understanding these flaws isn’t just about quality control; it’s about protecting your brand’s reputation. One small defect—a single slub or shade bar—can get an entire batch rejected by a discerning buyer. And let’s be honest, I’ve had bolts come in looking perfect until we cut into them and found stop marks hiding beneath the surface layer.

At Pura Fabric, we’ve learned the hard way that catching defects early saves time, money, and client trust. It’s not enough to just know what a “mispick” is—you need to understand why it happened and whether it’s fixable downstream.

Why Do Fabrics Have Defects/Faults?

Defects don’t appear out of nowhere. They’re symptoms of breakdowns somewhere in the production chain. Here’s where things usually go sideways:

• Faulty yarn: Inconsistent thickness, weak twist, or contaminated fibers
• Flying dust and lint in open-weave areas like knitting sheds
• Machine inefficiency: Worn parts, misaligned guides, or poor maintenance logs
• Improper machine settings: Tension imbalances, incorrect beat-up force
• Excessive or loose loom tension: Especially problematic on high-speed air-jet looms
• Loose mechanism fixation: Shuttle carriers, take-up rollers—if they wobble, you’ll pay for it later
• Dyeing and finishing errors: Uneven padding, temperature spikes, pH drift
• Sizing issues: Too much starch leads to brittleness; too little invites breakage
• Count variation in yarn supply: Even ±5% deviation can cause shade banding post-dye

I once worked with a supplier who swore their warp tension was calibrated perfectly—until we ran a 200-meter test cut and found stop marks every 18–22 meters. Turns out, their braking system engaged inconsistently after power fluctuations. Not something you catch in a lab dip.

Case Study: The Hidden Cost of CSV (Center-to-Selvage Shade Variation)

A fast-fashion client ordered 10,000 meters of indigo denim. First few rolls looked flawless. But once the pattern marker hit the cutting floor, operators noticed darker edges along the selvages. We measured the difference: ΔE = 3.2 between center and edge—just over the acceptable threshold (ΔE ≤ 2.5).

The root cause? Uneven dye penetration due to excessive beam density during warp preparation. Higher compaction meant less liquor flow at the roll core vs. outer layers.

We had two choices:

1. Re-dye the whole lot (cost: $4.70/m + energy)
2. Accept it and adjust markers to avoid placing key panels near selvages

We chose option 2—but only after testing shrinkage across zones. Found another issue: edge areas shrank 1.3% more than center. Had to widen seam allowances by 2mm on side seams. Saved cost short-term, but added complexity in grading.

Lesson? Never assume uniformity—even if the mill certifies it.

Different Types of Fabric Defects by Defects Producing Source

Fabric flaws originate at various stages: from raw yarn input to final inspection. Knowing which phase introduced the defect helps determine responsibility—and whether it’s salvageable.

Fabric Defects Produced During Manufacturing

These occur during weaving or knitting and often stem from mechanical faults or human error in setup.

• Broken Yarn
• Missing Yarn
• Color Yarn
• Slub
• Spot
• Big Thread
• Knot/Nap
• Line Mark
• Uneven Dyed
• Mispick
• Stop Mark

Some of these—like broken yarn—are immediate red flags. Others, like line marks, might only become apparent under certain lighting conditions or after washing.

Micro-note:

On one viscose twill run, we saw recurring “nap” defects every ~38 cm. Traced it back to a faulty doffer comb on the carding machine. Once fixed, defect frequency dropped from 1 in 12 meters to 1 in 200+.

Finishing Process Defects of Fabric

Finishing adds value—but also risk. These defects often emerge during heat setting, sanforizing, brushing, or calendering.

• Burl Mark
• Crease Mark
• Hole
• Miss Print
• Joint / Splice
• Shade Bar
• Broken Selvage

Crease marks, for example, happen when damp fabric folds during storage or transport. Steam pressing sometimes reduces visibility, but never fully erases them—especially on tightly woven poplins or acetate blends.

One time, a shipment sat in a humid warehouse for three weeks before inspection. The top 10 meters were covered in watermark shadows. Tried steaming—helped slightly. Decided to use those sections only for internal linings.

Dyeing and Printing Process Defects of Fabrics

Color application is both art and science. When either fails, the results are glaring.

• Bow/Skew
• Color Out
• Uneven Print
• Uneven Dye

“Color out” means the dye didn’t transfer properly—could be due to exhausted dye bath, low liquor ratio, or fiber maturity issues (common in ring-spun cotton with immature fibers).

Uneven print? Often tied to squeegee pressure inconsistency or screen mesh blockage. If you’re printing geometric patterns, even a 0.5 mm misalignment ruins registration.

List of Different Types of Fabric Defects

Let’s go deeper into the most common ones—with real-world context.

Slub

A slub is a thickened section in a yarn, resulting in a raised bump in the fabric. While intentional in slub jersey or seersucker, random slubs are defects.

Mechanically, slubs form when roving feeds unevenly into the drafting zone of a spinning frame. Could be due to worn aprons or improper roller settings.

In worsted wool we’ve seen slubs as large as 4–5x normal diameter. On lightweight voile? Even a 1.5x bulge shows under backlighting.

Fix it? You can’t. Best practice: isolate affected sections during spreading. Use software like Lectra Modaris or Gerber Accumark to flag irregularities before cutting.

Knot

Tiny, tight clusters of tangled fiber or thread—usually from poor joining during warping or weft insertion.

Knots matter more than you think. In fine shirting (80s–100s count), even a micro-knot can pop during sewing, especially near buttonholes where stress concentrates.

Preferred knot strength: ≥80% of original yarn tenacity. Anything below 60%, reject.

Pro tip: Run a tape test. Stick clear tape over suspected knots, peel gently. If fibers pull loose, it’ll likely fail under needle penetration.

Thick Yarn

When one yarn strand is noticeably thicker than its neighbors, it creates visual distortion.

Common in carded cotton where neps aren’t removed efficiently. Also happens with filament tow breaks rejoining mid-process.

On dark fabrics, thick yarns reflect light differently—looks like a shadow stripe under showroom lighting.

We tested this on a polyester-cotton blend: thick yarns increased local GSM by 12–15%. Not huge, but enough to affect drape symmetry.

Thin Yarn

Opposite problem: a thinner-than-standard yarn creates a sheer line or weakness point.

Particularly dangerous in load-bearing zones—think shoulder seams in jackets.

Had a case where thin warp ends led to seam slippage during fit testing. Grab strength dropped from 28 kg to 19 kg across the defect zone.

Solution? Reinforce with fusible tape—but only if hand feel allows. Otherwise, reroute patterns away from flaw lines.

Running Shade Variation

Lengthwise color shift within the same roll. Head-to-middle-to-end should match. If not, you’ve got running shade.

Measured using spectrophotometers. Acceptable ΔE ≤ 1.5 for solid colors; ≤2.0 for fashion shades.

But here’s the kicker: sometimes the machine reads “within spec,” but under north-light windows, the gradient is obvious. Human eye beats machines sometimes.

I prefer checking under three light sources: daylight, store LED, and incandescent. If shade shifts in any, treat it as suspect.

CSV – Center to Selvage Shade Variation

Width-wise color difference: center vs. edges.

Caused by uneven dye flow in jig or beam dyeing. Beam density matters—too tight, and inner layers absorb less dye.

CSV increases fabric waste because you can’t place symmetrical panels across the width. Marker efficiency drops by 6–10% easily.

Once, a mill claimed their beams were wound evenly. We asked for torque logs—turns out, tension varied by 18% across the traverse. Got compensation for extra consumption.

Miss Yarn

A missing end or pick creates a gap—sometimes invisible until stretched.

In knits, this causes runs. In wovens, it may hold until washed.

Test method: stretch fabric diagonally across a grid. Any discontinuity becomes obvious.

Repairable? Only with skilled mending—but not viable at scale. Better to downgrade usage (e.g., accessories instead of main garments).

Color Yarn

Contrasting-colored foreign yarn woven into the fabric. Usually from leftover fibers in creels or mixed bobbins.

Even a single red fiber in navy suiting stands out like a sore thumb.

Prevention: enforce strict changeover protocols. Clean beams, carriers, and shuttle boxes between lots.

Pura Fabric uses coded spools per color family now. Reduces cross-contamination risk significantly.

Fabric Hand Feel

Not always measurable, but instantly noticeable.

Should the fabric feel crisp? Soft? Silky? Any deviation counts as a defect.

For example, over-softened cotton can feel greasy—bad for structured blazers. Under-softened terry feels scratchy against skin.

We once received a batch of brushed fleece that felt stiff despite correct silicone finish. Lab test showed residual alkali from desizing—pH 9.1 instead of neutral 7.0. Washed it again before release.

Hand feel is subjective—but document standards anyway. Keep physical swatches labeled with descriptors: “smooth, moderate resilience, slight warmth.”

Hole

Non-negotiable defect. A hole compromises integrity.

Causes: broken needles, birdnesting in knitting, chemical degradation, or abrasion during handling.

Even pinholes matter on windbreakers or rainwear. Hydrostatic head tests expose them immediately.

If detected early, patching isn’t unthinkable—but transparency with clients is key.

Uneven Dye

Dye distribution should be consistent across length and width.

Occurs due to:

• Poor liquor circulation
• Rapid heating rates (>2°C/min in reactive dyeing)
• Insufficient batching time

Cone dyed yarns often show pie-wedge effects if cones aren’t packed uniformly.

Check method: lay fabric flat, rotate slowly under directional light. Shadows indicate depth differences.

Uneven Print

Misaligned screens, clogged nozzles (digital), or inconsistent paste viscosity.

On floral prints, slight blurring might be acceptable. But on geometric designs? No mercy.

Digital printers need regular nozzle checks—some auto-clean every 4 hours. Still, manual verification weekly prevents disasters.

Foreign Yarn / Contamination

Any fiber not belonging in the fabric: polypropylene string, hair, synthetic trash.

Most common in open-end spinning mills or shared processing lines.

Can trigger allergic reactions or snagging in technical wear.

Our QC team uses UV lights during night shifts—certain synthetics fluoresce differently.

Crease Mark

Permanent fold lines caused by improper storage or rolling under tension while damp.

Steam can relax minor creases, but set-in ones remain visible, especially on mercerized cotton or rayon blends.

Prevention: ensure fabric cools completely before winding. Use anti-crease rollers where possible.

Fabric Skew

Weft threads angled relative to selvage.

Measurable: skew > 3% is unacceptable for tailored garments.

Caused by uneven take-up or asymmetric tension in stenter frames.

Remedy: de-skew during pre-shrinking or apply corrective tension in finishing.

But beware: forcing correction on delicate knits can distort courses.

Fabric Bowing

Weft yarns curve like a bow across the width.

Looks similar to skew but harder to correct.

Typical in wide-width jersey dyeing when center dries slower than edges.

Lay fabric on a grid: measure straightness of course lines. Deviation > 1.5 cm per meter? Flag it.

Stain / Spot / Dirt

Oil, wax, perspiration, or machine grease transferred during handling.

Some stains appear only after washing—latent contamination.

Avoid plastic wrap directly on fabric; can trap moisture and promote mildew spots.

Always inspect before and after washing. Some dirt bonds permanently during curing.

Watermark

Moisture trapped between layers creates dull patches.

Common in poorly ventilated warehouses.

Unlike stains, watermarks don’t wash out—they leave mineral deposits or alter fiber swelling.

Best avoided by proper stacking and breathable packaging.

Fabric Way

Refers to correct grain alignment—warp, weft, bias orientation.

Wrong fabric way distorts drape and fit.

Example: cutting a sleeve with a twisted grain leads to spiraling when sewn.

Always verify grain before spreading. Use chalk lines or laser guides.

Line Mark

Streaky, linear discoloration—common in denim and twills.

Arises from uneven dye absorption during rope dyeing or inconsistent squeegee pressure in printing.

In denim, line marks often follow warp direction. Can be minimized by adjusting indigo vat immersion time.

We reduced line mark frequency by 70% simply by slowing down the exit nip roller speed by 12%.

Broken Yarn

Self-explanatory: a severed warp or weft thread.

More common in high-tension weaving setups or with brittle recycled yarns.

Inspect selvage closely—broken ends often start there.

Automated looms detect breaks via sensors, but older models miss intermittent ones.

Bad Selvedge

Irregular, frayed, or overly tight selvage.

Affects cutting accuracy and can pull fabric out of square.

Some bad selvages are trimmed off automatically; others require manual grading.

Width tolerance: ±3 mm acceptable. Beyond that, affects lay planning.

Loose Warp

A slack warp thread floats above the weave structure.

Creates loops vulnerable to snagging.

Usually due to temporary tension drop during weaving stoppage.

Hard to detect visually unless backlit. Stretch test reveals looseness.

Mispick

One weft pick missing entirely.

Leaves a horizontal gap—one full float where interlacing should be.

Caused by shuttle malfunction or air-jet timing error.

Visible under raking light. Often paired with stop marks.

Stop Mark

Occurs when a loom stops, tension relaxes, then restarts—creating a denser band of fabric.

More prominent in synthetic fibers (polyester, nylon) due to lower elasticity recovery.

Typical interval: matches stop duration. A 4-minute stop? Expect a 6–8 cm dense zone.

Cutting strategy: avoid placing critical panels over stop zones. Use outside shoulders or pocket flaps.

Other Defects of Fabric

Beyond the main list, here are additional issues worth monitoring:

• Double pick
• Splicing
• Horizontal lines
• Drop stitches
• Misprinting
• Barre
• Abrasion marks
• Snags
• Needle lines
• Coarse pick
• Coarse end
• Broken pick
• Broken end
• Missing end
• Filling bar

Barre, for instance, appears as repetitive horizontal stripes in knits—often due to feeder tension variation.

Needle lines show up post-sewing when damaged needles create aligned snags. Always inspect needle bars monthly.

Abrasion marks come from guide rollers with rough surfaces. Replace every 6 months under heavy use.

Case Study: The Barre Problem That Killed a Swimwear Line

We launched a new LYCRA® blend swim knit. Samples passed all tests. Bulk arrived—and under bright sunlight, faint horizontal bands appeared every 1.2 inches.

Turns out, one feeding cam was slightly misaligned, causing periodic stitch length variation. Not enough to fail gauge checks (+/- 0.3 mm), but enough to scatter light differently.

Options:

• Reject 15,000 meters (loss: $68k)
• Accept and sell as “textured look” (risky branding move)
• Cut exclusively on the bias to disrupt banding pattern

We went with bias cutting. Altered design silhouettes, used asymmetry as a selling point. Clients thought it was intentional texture.

Still makes me nervous though—walking that line between innovation and deception.

Final Thought

Defects aren’t just flaws—they’re feedback. Each one tells a story about tension settings, humidity levels, operator fatigue, or material history. At Pura Fabric, we don’t just grade them; we interrogate them. Because the moment you stop asking why a slub formed or how a shade bar slipped through, you’re one step closer to a customer rejection email. Stay curious, stay sharp.