Knitwear Finishing & Assembly: Complete OEM/ODM Technical Guide

Role of Finishing in Knitwear Manufacturing

Finishing transforms raw knitted panels into fully shaped, stable, and wearable garments. Without proper finishing, even a well-knitted garment may show:

• Shrinkage or stretching

• Uneven measurements

• Fuzzy or rough surface

• Curling edges

• Off-shape panels

• Color fading

• Poor drape

Finishing must be controlled precisely because different yarns and stitch structures behave differently in water, steam, and heat.

Washing Processes

Washing is the first major step in finishing. The goal is to stabilize the yarn, remove excess oils, soften the surface, and achieve the correct drape and hand-feel.

Washing Methods Based on Fiber Type

Wool, Merino, Cashmere

• Cold or lukewarm washing

• Low agitation

• Gentle enzyme wash for hand-feel improvement

• Fiber-protecting agents to prevent felting

Cotton, Organic Cotton, Blends

• Warm wash

• Enzyme treatment to reduce hairiness

• Stabilization for dimensional control

Viscose, Modal, Tencel

• Extremely delicate

• Higher shrinkage tendency

• Requires controlled agitation and short wash cycles

Acrylic, Polyester, Performance Fibers

• Stable and easy to wash

• Minimal shrinkage

• Anti-static or softener treatment if required

Purpose of Washing

• Achieve expected shrinkage before measurement

• Balance tension in the panels

• Clean yarn oil and machine residue

• Improve hand-feel

• Prepare garment for blocking and pressing

Drying & Dehydration

After washing, knitwear must be dried carefully to prevent distortion.

Dehydration Methods

• Spin extraction (low RPM for delicate fibers)

• Air drying for luxury materials

• Controlled tumble drying for cotton-based products

Drying Considerations

• Over-drying causes shrinkage

• Under-drying causes panel growth

• Temperature control is essential for viscose and wool

Factories often calibrate drying parameters differently for each yarn batch.

Blocking and Shaping

Blocking is the process of shaping knitwear to final measurements.

Why Blocking Matters

• Controls shrinkage

• Ensures measurement accuracy

• Stabilizes seams and rib trims

• Sets the final silhouette

• Ensures consistency across bulk production

Blocking is especially important for complex stitch patterns such as:

• Cable

• Waffle

• Lace / pointelle

• Jacquard

• Links-links structures

Blocking Tools

• Steam plates

• Blocking boards

• 3D body blocks

• Flat frames

Blocking is repeated in both sampling and bulk production to ensure consistency.

Linking Techniques

Linking is where the front, back, sleeves, and trims are joined. Linking quality determines seam strength, stretch recovery, and overall garment appearance.

Types of Linking

Loop-to-loop linking (Premium Method)

• Each loop is linked one by one

• Strongest and cleanest finish

• Common in luxury menswear and fine-gauge knitwear

Chain linking

• Faster

• Good balance between aesthetics and efficiency

• Widely used for mid-gauge sweaters

Overlock joining

• Used in cut & sew knitwear

• Good stretch recovery

• Less premium appearance than loop-to-loop

Linking Considerations

• Match gauge with linking needle pitch

• Ensure equal tension at seams

• Maintain symmetry in armholes and sleeve caps

• Control stitch spacing to avoid bulky seams

Stitch-Off & Panel Preparation

Before linking, panels must be inspected, trimmed, and prepared.

Panel Preparation Workflow

1. Line checking for holes or dropped stitches

2. Trimming excess yarn

3. Edge clean-up for neat linking

4. Ensuring left & right symmetry

5. Pre-measurement before linking

Proper panel preparation eliminates future QC issues during final inspection.

Neckline & Collar Construction

Collars and necklines require special handling due to their stretch, structure, and shaping demands.

Common Neckline Types

• Crewneck

• V-neck

• Turtleneck

• Mock neck

• Polo collar

Technical Notes

• Polo collars must be fully-fashioned for best appearance

• Rib collars must be stabilized with plating

• V-neck angles must match panel shaping precisely

A poor neckline ruins even a premium sweater, so factories pay special attention to this area.

Pressing & Steam Finishing

Pressing sets the final look and feel of the garment.

Purpose

• Smooth fabric surface

• Enhance drape

• Stabilize dimensions

• Improve visual appearance

• Remove creases

Tools

• Steaming tables

• Steam irons

• Vacuum tables

• Form presses

Key Considerations

• Avoid over-pressing ribs

• Prevent shine on viscose

• Maintain loft for wool and cashmere

• Avoid flattening textures such as cable or waffle

Pressing must enhance—not damage—the knit structure.

Assembly Workflow Overview

A complete OEM/ODM assembly process typically includes:

1. Panel inspection

2. Panel trimming

3. Linking or sewing

4. First measurement

5. Washing

6. Blocking

7. Second measurement

8. Pressing

9. Thread trimming

10. Final QC

11. Packing

Factories use MES systems to track each step for consistency.

Quality Control in Finishing & Assembly

QC is performed at multiple stages:

During Linking

• Seam alignment

• Stitch tension uniformity

• Clean joining at the underarm

• Symmetry of sleeve caps

After Washing

• Shrinkage within tolerance

• No twisting or skewing

• Balanced lengths/widths

• Surface appearance check

During Blocking

• Accurate measurement

• Rib trim stability

• Neckline curve accuracy

Final Inspection

• Hole check under LED

• Pilling resistance

• Color uniformity

• Hand-feel and drape evaluation

• Proper folding and packaging

Factories use AQL standards depending on brand requirements.

Common Finishing Defects & Solutions

Shrinkage Over Tolerance

Cause: high agitation, incorrect wash temp
Fix: reduce agitation, adjust stitch density, pretest every yarn lot

Panel Twisting

Cause: uneven yarn twist or machine tension
Fix: yarn rebalancing, tension recalibration

Seam Bulkiness

Cause: incorrect linking pitch
Fix: match needle pitch to garment gauge

Collar Stretching

Cause: weak rib structure
Fix: rib plating with nylon, tighter density

Color Fading

Cause: incorrect dyeing or washing
Fix: reduce heat, upgrade dyeing process

Sustainability in Finishing

Sustainable finishing helps reduce environmental impact:

• Low-water washing

• Ozone washing for cotton blends

• Reduced softener use

• Recycled steam

• Solar-heated drying systems

• Zero-waste manufacturing (especially paired with 3D knitting)

Sustainability is a strong selling point for international buyers.