Industrial Coverstitch Machine for Stretch Fabrics

Industrial coverstitch machines are excellent for sewing elastic and knit fabrics. The coverstitch forms a class 600 multi-thread cover chain stitch, which has inherent stretch. It will not snap easily when the fabric is pulled, unlike the lockstitch from an ordinary flat sewing machine. This machine is widely used for hemming T-shirt bottoms, cuffs, sportswear leg openings and lingerie.

Suitable Fabrics

Cotton knits, fleece, ribbing

Spandex elastic fabric, high-stretch nylon, swimwear fabric, yoga wear material

Note: The coverstitch machine only performs hemming. It does not trim or overlock raw fabric edges. For joining seams and finishing cut edges, it is usually paired with a 4-thread overlock machine.

Key Machine Settings for Stretch Fabrics

Needle: Use ballpoint needles (UY128GAS). The rounded tip slips between knit yarns instead of cutting them, preventing holes and skipped stitches.

Fine stretch fabric: size 70/75

Heavy elastic fabric: size 80/90

Thread: Polyester thread for top needles; nylon looper thread is recommended for better elasticity and soft stitch.

Thread Tension: Keep tension loose. Over-tight stitches will break once the fabric stretches.

Differential Feed: The most critical adjustment for knits.

If finished fabric stretches longer after sewing: adjust differential feed to slightly gather the material and counteract fabric elongation.

Wavy edges on thin high-elastic fabric: fine-tune differential feed and reduce presser foot pressure, to avoid stretching fabric while feeding.

Needle Plate: Use a small-hole needle plate for ultra-thin elastic fabric, to stop fabric from sinking into the needle hole and wrinkling.

Common Troubleshooting

Skipped stitches: Wrong needle size or misaligned guard needle.

Elongated fabric / wavy seam: Improper differential feed or excessive presser foot pressure.

Broken stitches when stretched: Too tight thread tension or insufficient elasticity of looper thread.