Bernette B68 Airlock Serger and Coverstitch Machine Instruction Manual

1. Introduction and Overview

The Bernette B68 Airlock Serger and Coverstitch Machine is a versatile sewing solution designed for both novice and experienced users. This machine combines the functionalities of an overlock machine and a coverstitch machine, offering a wide range of stitching options for various fabric types and projects. Key features include an automatic air threader for simplified setup, five LED lights for enhanced visibility, and adjustable controls for precise stitch customization.

This manual provides essential information for the safe and effective operation, maintenance, and troubleshooting of your Bernette B68 Airlock machine. Please read it thoroughly before initial use.

2. Key Features

• Automatic Air Threader: Simplifies looper threading, reducing setup time and effort. Color-coded threading paths further assist in accurate threading.
• Integrated LED Lighting: Five built-in LED lights illuminate the entire sewing area, ensuring clear visibility and reducing eye strain during intricate work.
• Versatile Stitching Options: Capable of 2, 3, 4, or 5-thread overlock, chain stitch, and coverstitch. Ideal for a variety of projects from delicate materials to heavy-duty fabrics.
• High-Speed Operation: Achieves up to 1300 stitches per minute (SPM) for efficient and fast project completion.
• Adjustable Stitch Length and Presser Foot Pressure: Allows customization of stitch length (1-4mm) and presser foot pressure to suit different fabric thicknesses and types, ensuring consistent stitch quality.
• Large Slide-On Table: Provides an expanded workspace, beneficial for quilting, embroidery, and larger garment projects.
• Micro Thread Control (MTC) System: Ensures precise thread adjustments for perfectly aligned stitches.

3. Setup

3.1 Unpacking and Placement

Carefully remove the machine from its packaging. Place the Bernette B68 on a stable, level surface with adequate space for fabric handling. Ensure the power cord can reach an electrical outlet without strain.

3.2 Attaching the Slide-On Table

The large slide-on table provides additional workspace. Align the table with the machine's free arm and slide it into place until it locks securely. This is particularly useful for larger projects like quilting or garment construction.

Figure 3.2: The Bernette B68 Airlock Serger displayed with a selection of included accessories, such as different presser feet, for enhanced versatility.

3.3 Threading the Machine

The Bernette B68 features an automatic air threader for the loopers, significantly simplifying the threading process. Follow the color-coded threading paths indicated on the machine for each thread. For detailed instructions on specific threading sequences for different stitch types, refer to the machine's internal threading guide or the comprehensive manual provided with the product.

Figure 3.3: A front view of the Bernette B68 Airlock Serger and Coverstitch Machine, showcasing its compact design and thread guides.

4. Operating Instructions

4.1 Stitch Selection and Adjustment

The Bernette B68 offers a variety of stitch types, including 2, 3, 4, and 5-thread overlock, chain stitch, and coverstitch. Select the desired stitch type using the machine's controls. Adjustments for thread tension, stitch length, and differential feed are crucial for achieving optimal stitch quality on different fabrics.

• Thread Tension: Use the color-coded tension dials to adjust the tension for each thread. The Micro Thread Control (MTC) system allows for fine-tuning.
• Stitch Length: Adjust the stitch length between 1-4mm using the dedicated dial to suit your fabric and project requirements.
• Differential Feed: This feature helps manage fabric feeding, preventing stretching on knits and puckering on fine fabrics. Adjust as needed for your material.
• Presser Foot Pressure: Customize the presser foot pressure to match the thickness of your fabric, ensuring smooth and even feeding.

Figure 4.1: The Bernette B68 Airlock Serger highlighting its adjustable stitch length and presser foot pressure capabilities for various fabric types.

4.2 High-Speed Stitching

The machine operates at up to 1300 stitches per minute (SPM), allowing for rapid project completion. Maintain a steady pace and guide the fabric smoothly for best results at high speeds.

Figure 4.2: The Bernette B68 Airlock Serger in action, illustrating its high-speed stitching capability of up to 1300 stitches per minute.

4.3 Using the Knife

The integrated knife trims the fabric edge as you sew, creating a clean finish. For coverstitch operations, the knife can be disengaged or raised. Refer to your machine's specific instructions for engaging and disengaging the knife.

Figure 4.3: The Bernette B68 Airlock Serger actively stitching fabric, demonstrating its operational use.

5. Maintenance

Regular maintenance ensures the longevity and optimal performance of your Bernette B68 machine.

• Cleaning: Regularly clean lint and dust from the machine's interior, especially around the loopers, feed dogs, and knife area. Use a soft brush and a vacuum cleaner designed for sewing machines.
• Needle Replacement: Replace needles frequently, especially when working with different fabric types or if you notice skipped stitches or thread breakage. Always use the correct needle type and size for your fabric.
• Lubrication: Consult your full instruction manual for specific lubrication points and recommended lubricants. Proper lubrication prevents wear and tear on moving parts.
• Professional Servicing: It is recommended to have your machine professionally serviced by an authorized Bernette technician periodically, typically once a year, to ensure it remains in top working condition.

6. Troubleshooting

This section addresses common issues you might encounter with your Bernette B68. For more detailed troubleshooting, refer to the comprehensive manual.

• Skipped Stitches: Check if the needle is bent or dull, ensure it's inserted correctly, and verify that the correct needle type is being used for the fabric. Adjust thread tension if necessary.
• Thread Breakage: Inspect for incorrect threading, excessive thread tension, burrs on the needle plate or loopers, or a damaged needle.
• Uneven Stitches/Puckering: Adjust differential feed, presser foot pressure, and thread tension. Ensure the fabric is not being pulled or pushed excessively.
• Machine Not Starting: Check power connection, ensure the foot pedal is properly connected, and confirm the power switch is on.

7. Specifications

8. Warranty and Support

For warranty information, please refer to the warranty card included with your Bernette B68 machine or visit the official Bernette website. For technical support, service, or to purchase accessories, please contact your authorized Bernette dealer or Bernette customer service.

Keep your purchase receipt and machine's serial number readily available when contacting support.