Fabric Snagging Test Methods
1.What is Snagging in Fabric?
In this article points like what is snagging in fabric and Fabric snagging test methods are covered. An article covering points like factors affecting fabric snagging, how to prevent fabric snagging, snagging resistance fabric/ anti-snagging fabric will be published soon.
“Snagging is defined as a defect caused by the pulling or plucking of yarns from a fabric surface.”
The snagging of a specific fabric in actual wear varies with the individual wearer and general condition of use. Knits used in a more rugged outerwear application, such as men's slacks, result in very high and unacceptable levels of snagging.
2. Fabric Snagging Test Methods
ASTM has following fabric snagging test methods for testing snag resistance of fabric.
2.1 Mace Test
2.1.1 Test Method
In mace test, fabric specimens are placed on a cylindrical drum in tubular form. A mace (spiked ball) is allowed to bounce randomly against each rotating specimen. Snags could occur to a fabric due to the bouncing action of mace i.e. spiked ball over fabric specimen. The degree of fabric snagging is then evaluated by comparison of the tested specimens with visual standards that may be either fabric or photographs of fabrics.
2.1.2 Mace Snag Tester
Assessment/Grading:
The observed resistance to snagging is reported on a scale ranging from No. 5 (no snagging) to No. 1 (severe snagging).
Suitability of Test:
This method is suitable for a range of woven and knitted fabrics made from textured or untextured yarns containing staple or continuous filaments.
2.2 Bean Bag Test
2.2.1 Test Method
In bean bag test, fabric specimens are cut into dimensions of approximately 9 x18 cm. This is folded in half and sewn into a pouch as shown in fig.2. A "bean bag" weighing approximately 1 lb is placed in the pouch. After placing the bean bag into the pouch of test specimen, the top/open part of that pouch is sewn and closed. This closed pouch is placed in the cylinder, which has eight baffle bars with a series of tenter pins protruding from them at an angle. After placing the pouch in cylinder the machine is started because of which the test specimen is subjected to a random tumble action. The tenter pins act to snag the specimen as the cylinder rotates. The tenter pins carry it (pouch) to the top of the chamber, where it pulls away and drops to the bottom. The specimen is subjected to 100 revolutions of the cylinder.
The specimen is then removed and the degree of snagging is evaluated by two methods:
Comparison of the tested specimen with visual rating standards that may be either snagged fabrics or photographs of snagged fabrics.
The resistance to snagging can be reported in the first case on a numerical scale ranging from No.5 (no or insignificant snagging) to No.1 (severe snagging), and simply as number of snags in the second case.
The bean bag method to have the following advantages over other snagging tests in use:
Snagging is multidirectional in end use and the bean bag method simulates this very effectively.
This test is more realistic. The test fabric is mounted in a relaxed state nad tension occurs only as the weighted bean bag pulls the test specimen away from the tenter pins where it was impaled.
Test data obtained from this test method is less variable.
2018-09-28 11:16