Operator's Guide for Singer 14SH644 and 14SH654 Overlock Machine

Important Information

This guide covers the operation of the Singer 14SH644 and 14SH654 overlock machines. Always disconnect the power supply before performing maintenance, changing needles, or replacing light bulbs. Ensure the machine is used on a flat, stable surface and keep fingers away from moving parts during operation.

Getting Started and Setup

Before sewing, ensure the machine is properly prepared:

• Power Connection: Connect the foot controller and power cord to the machine and the wall outlet. Use the power switch to turn the machine on or off.
• Thread Guide Holder: Fully extend the thread guide holder until the joints click into place.
• Needle Insertion: Ensure the needle is inserted with the flat surface facing the rear. Use Singer #2022 needles.

Threading the Machine

The machine uses a color-coded system for threading. Follow the order 1 to 4:

• Orange: Upper looper thread.
• Yellow: Lower looper thread.
• Green: Right needle thread.
• Blue: Left needle thread.

Always thread the needles last to prevent misthreading the lower looper. Use the provided tweezers to assist in threading the looper area.

Machine Adjustments

Achieve the desired stitch quality by adjusting the following settings:

• Stitch Length: Adjust the dial to 3mm for most conditions, 4mm for heavy fabrics, or 2mm for light fabrics.
• Seam Width: Adjust by changing the needle position or using the width adjustment knob.
• Presser Foot Pressure: Pre-adjusted for medium fabrics. Increase for heavy fabrics or decrease for lightweight fabrics using the regulating screw.
• Differential Feed: Use the lever to stretch or gather fabric. Set to 1.0 for normal overedge stitching.

Sewing Techniques

The machine supports various techniques including:

• Rolled Hem: Requires specific settings for the seam width finger and stitch length.
• Flatlock: Achieved by adjusting tension settings to flatten the seam.
• Overlock Blind Hem: Used for durable finishes on knitwear.
• Pin Tucks: Decorative technique using a water-soluble marker.

Maintenance and Care

Regular maintenance ensures optimal performance:

• Cleaning: Frequently remove lint from the looper and knife area using a dry brush.
• Oiling: Periodically oil the machine at designated points using sewing machine oil.
• Knife Replacement: Replace the stationary knife when it becomes dull.
• Light Bulb: Ensure the bulb has cooled before replacement. Use the specified bulb type based on your local voltage (110-127V or 200-240V).

Troubleshooting

If you encounter issues, check the following:

• Fabric does not feed: Lengthen stitch length or adjust presser foot pressure.
• Needle breaks: Ensure correct insertion, do not pull fabric while sewing, and check for bent needles.
• Thread breaks: Check threading path, look for tangles, or adjust tension.
• Stitches skip: Replace the needle or check threading.

Technical Specifications

The machines feature a maximum speed of 1,300 spm, a stitch length of 1-4mm, and a differential feed ratio of 1:0.7 to 1:2.0. The 14SH644 and 14SH654 models weigh 6.0kg and 6.2kg respectively.