The resistance of shoe laces to wear and tear due to abrasion is determined by abrading two samples of the lace against each other under a specified tension and finding the number of rubs which cause one of the laces to wear off till it breaks into two. 

One of the laces used in the test is formed into a loop and suspended in a vertical plane. One end of the second lace is held in a rotating grip. The second lace is passed through the loop of the first lace and a specified dead weight suspended from its free end to keep both the laces under tension. The movement of the grip causes rubbing action between the two laces, which continues till one of them fails. The number of rubs needed to cause failure gives a measure of the resistance of the lace to wear

Technical specification