Janome 644D Serger Manual

The Janome 644D is a professional-grade 3/4 thread serger with differential feed, built-in rolled hem capability, color-coded threading system, adjustable stitch length and width, easy-to-use tension dials, built-in thread cutter, free arm capability, and LED lighting. Designed for home and professional use, it handles a variety of fabrics from lightweight to heavy-duty materials. Below are key sections for safety, features, setup, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Color-coded threading system, Differential feed mechanism, Built-in rolled hem, Free arm, LED work light, Built-in thread cutter.

Installation & Setup

Unpack and inspect all components. Place on stable, level surface.

1. Remove packaging materials and protective covers from machine.
2. Attach power cord to machine and plug into appropriate outlet.
3. Install presser foot: Lower presser foot lever and snap foot into place.
4. Wind and install loopers and needles following color-coded guides.
5. Adjust machine height and position for comfortable operation.

WARNING! Keep fingers away from moving parts during operation. Always unplug when not in use.

First-Time Operation

Power on serger; test on scrap fabric first.

1. Thread machine: Follow color-coded threading path from right to left.
2. Insert needles: Ensure needles are properly seated and facing correct direction.
3. Set tensions: Begin with factory settings (usually 4-5) and adjust as needed.
4. Test stitches: Use scrap fabric to check stitch formation and make adjustments.
5. Practice basic seams: Begin with simple overlock stitches before advanced techniques.

CAUTION! Always use proper needle type and size for your fabric. Replace bent or damaged needles immediately.

Specifications

• Machine Type: 3/4 Thread Serger with Differential Feed
• Stitch Types: Overlock, Rolled Hem, Flatlock, Ribbing
• Stitch Length: 1-4mm adjustable
• Stitch Width: 3-7mm adjustable
• Differential Feed: 0.7-2.0 ratio
• Speed: Up to 1300 stitches per minute
• Lighting: LED work light
• Presser Feet: Standard, Rolled Hem, Gathering included
• Power Requirements: 110V, 60Hz (or appropriate for your region)
• Weight: Approximately 15.4 lbs (7 kg)

Controls and Settings

Main controls located on front and side panels. Stitch length dial, stitch width dial, differential feed dial, tension dials, power switch.

Stitch Length Dial: Controls how long each stitch is (1-4mm). Stitch Width Dial: Adjusts how wide the stitch pattern is (3-7mm). Differential Feed Dial: Prevents fabric stretching or gathering. Tension Dials: Four separate dials for upper looper, lower looper, right needle, left needle. Rolled Hem Lever: Engages rolled hem function.

Threading the Serger

Follow color-coded threading path for easy setup.

1. Raise presser foot and lower needle to highest position.
2. Follow numbered threading sequence: Upper looper (yellow), lower looper (green), right needle (blue), left needle (red).
3. Ensure threads are properly seated in tension discs and guides.
4. Pull threads under presser foot and toward back of machine.
5. Test thread tension on scrap fabric before beginning project.

Tip: Always thread with presser foot raised to open tension discs.

Stitch Selection & Techniques

Versatile stitch options for various sewing applications.

1. Basic Overlock: Standard 3-4 thread seam finishing
2. Rolled Hem: Engage rolled hem lever for narrow hems
3. Flatlock: Creates decorative flat seams
4. Gathering: Use differential feed for even gathering
5. Decorative Stitches: Vary thread colors and types for creative effects
6. Seam Finishing: Professional edge finishing on woven and knit fabrics
7. Insertion: Attach lace, elastic, or trim with serger stitches

WARNING! Always test stitches on fabric scraps. Adjust tensions gradually for perfect results.

Maintenance & Cleaning

Regular maintenance ensures optimal performance and longevity.

1. Daily: Brush away lint and thread bits from loopers and feed dogs
2. Weekly: Oil machine according to manufacturer's instructions
3. Monthly: Check and tighten screws; inspect for wear
4. As needed: Replace needles; clean and oil shuttle race
5. Storage: Cover machine when not in use; store in dry area

CAUTION! Unplug machine before cleaning or maintenance. Use only recommended oils and cleaners.

Accessories

Standard accessories included with Janome 644D serger.

• Standard Overlock Foot
• Rolled Hem Foot
• Gathering Foot
• Lint Brush
• Thread Nets (4)
• Needles (assorted sizes)
• Hex Wrenches
• Tweezers
• Oil Bottle
• Instruction Manual

Warranty Information

Janome 644D comes with limited warranty covering defects in materials and workmanship. Warranty period varies by region. Proof of purchase required for warranty service. For warranty claims, contact authorized Janome dealer or service center. User damage, improper maintenance, or use of non-genuine parts may void warranty.

Troubleshooting

Service: Contact authorized Janome service center for professional repairs.

Support: Visit www.janome.com or contact local dealer for assistance.