Torn jeans and other clothing is a very popular style today. The strength of these tears must be designed and manufactured carefully to prevent the tears from extending excessively, thereby degrading the style look. This requires quantification of the tearing strength of the fabric in the test lab. The ASTM D1424 Elmendorf based tear test is the most popular test for measuring the tearing strength of most fabrics.
The Elmendorf test testing machine uses a falling pendulum to tear a fabric specimen. It measures the amount of energy required to perform the tearing operation by measuring the peak follow-through angle of the pendulum after the tearing action. The lower the follow-through angle the more energy has been transferred into tearing the specimen. The machine is setup to
provide this tearing energy information in grams-force. The fabric specimen is 76.2 mm (3 in) tall by 101.6 mm (4 in) wide. It is pre-notched with a 12.7 mm (0.5 in) by 12.7 mm (0.5 in) notch at the center of the top of the fabric specimen. The falling pendulum propagates this pre-notch to a complete tear through the center of the fabric specimen.
One of the variables in Elmendorf tear testing is the orientation of the fabric. WARP direction of the fabric is in line with the weaving machine. WAFT direction is perpendicular to the orientation of the weaving machine. Woven fabrics are usually stronger in the WARP direction. The direction of orientation of the fabric should be noted in the test report.
Recommended Test Machine
Tests for the tear resistance of paper, fabrics, and plastics
Arm weight capacities from 100 g to 6,400 g (0.22 lbm to 14.1 lbm)
Satisfies numerous testing standards
