Stitch Type

Stitches: Difference between lockstitch and chainstitch

Chainstitch Machines

Lockstitch Machines

Stitches are formed by two or more sets of threads: 1 needle thread and 1 looper thread. Threads are bound together by interlacing and Inter looping, this forms a chain of thread on the underside of the fabric, creating the chainstitch.

Stitches are formed by at two sets of threads: 1 needle thread and 1 bobbin thread. Threads are bound by interlacing. The rotary hook containing the bobbin catches the needle thread after it goes through the fabric, the hook then carries the needle thread around the bobbin and the needle pulls the needle thread back up to the top of the fabric. The needle thread and bobbin thread become interlocked, forming a lockstitch.

Appears like lockstitch above and double chainstitch below.

Appearance is similar on both sides of the fabric.

No bobbin to change and interrupt sewing.

Operators must remove and replace the bobbin frequently.

More cost effective than lockstitch.

Replacing the bobbin interrupts productivity/increases labor costs. Some bobbins are automatically wound during sewing; others are purchased pre-wound from thread companies.

Looper threads feed from large cones.

Strength is higher than lockstitch.

Strength is lower than chainstitch.

Possibility of seam pucker formation is more than lockstitch.

Possibility of seam pucker formation is less than chainstitch.

Extensibility is 30%.

Extensibility is 30%. Sometimes less than that.

Chainstitch machine speed 8000 SPM.

Lockstitch machine speed 6000 SPM.

Interlacing: To cross one another, typically passing alternately over and under, as if woven together; intertwine. Inter looping: The loop of one thread passes through the loop of another thread. Extensibility: Capable of being extended.