The Exchange Test Method
A-7: Fabric Count
Issue Date: 30 Apr 1993
Revision Date: 09/30/2011
PURPOSE AND SCOPE:
To measure the fabric count. Fabric count which is expressed in umber of threads per unit length is used as an indicator of fabric quality in general. Generally, higher thread count results in stronger, more durable fabric with less possibility of yarn shifting.
PRINCIPLE:
The number of warp (ends) and filling (picks) for woven fabric or wales and courses for knitted fabric per unit distance are determined by using suitable magnifying and counting devices.
REFERENCE:
- 3.1 ASTM D 3775-08, Standard Test Method for Fabric Count of Woven Fabric.
- 3.2 ASTM D 3887-96(2008), Standard Specification for Tolerances for Knitted Fabrics.
APPARATUS:
- 4.1 Pick glass
- 4.2 Counting device
PROCEDURE:
- 5.1 Take at least 3 specimens greater than 5 x 5 cm (2 x 2 in.) from each garment from different places.
- 5.2 Condition the specimens for a minimum of 2 hours at 21° +/- 1C (70° +/- 2F) temperature and 65 +/- 2% RH.
- 5.3 The yarn counting should b done in the middle and not at the edge of the specimen.
- 5.4 Place the pick glass on the specimen resting on a flat surface. Look through the pick glass to determine whether the counting can be done more easily on the face or on the back. Count on either face or back, whichever is easier.
- 5.5 Line up the left edge of the opening in the base of the pick glass with the first yarn to be counted.
- 5.6 Use pick needle to point to the yarns as they are counted from one edge to the opposite edge of the base of the pick glass.
- Calculate the average fabric (thread) count of the three specimens for each direction of the fabric.
REPORT:
Report the average number of warp (ends), wales and filling (picks) or courses per cm, or per inch.