Page 173 - CTS - Sewing Technology - TP - Volume - 2-0

SEWING TECHNOLOGY - CITS

406 – Coverseam

Derivatives of the 401 chainstitch are the chainstitch coverseam stitch formations. The most common of these is
the 406 twin needle coverseam. This stitch type is formed using two needle threads and one looper thread and
its main uses are hemming of garments made from knitted fabric and elastic/lace attaching on underwear and
lingerie. (Fig 7)

Fig 7

Stitch type 407 coverseam is a three needle version of this stitch type. A four needle version is available but it is
not in common use.

503 – Two thread overedge (serging)
Overedge stitch formations are all contained under the 500 classification. 503 two thread overedge is the stitch
type used for single ply serging and the hemming of tee shirts. This is sometimes known as welting.

Stitch type 503 is not suitable for seaming operations as it is designed to collapse and flatten when a seam is
loaded laterally. (Fig 8)

Fig 8

504 – Three thread overedge
This stitch type is formed with three thread; it has one needle thread and two looper threads. Stitch type 504
has excellent extension and does not unravel easily. It is generally used for serging to stop fabric fraying and
for joining 2 or more plies together. These machines are capable of running at higher speeds which can aid in
increased productivity. (Fig 9)

Fig 9

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CITS : Apparel - Sewing Technology - Exercise 34