Two fabrics, 100% cotton and 100% nylon, were abraded with Stoll (inflated diaphragm), Schiefer, and Accelerotor instruments. Fabrics were given nine levels of abrasion, ranging from slight distortion of the fabric surface to fabric rupture, with each type of instrument. After abrasion, selected physical properties of the fabrics were measured and microscopic studies were made to determine the types of fabric, yarn, and fiber damage caused by the three abraders.The Stoll abrader caused severe fabric damage at very low levels of abrasion because the abradant pressure was highly localized in the center of the abraded area. The Schiefer and Accelerotor instruments caused uniform abrasion over the entire areas and abrasive damage to the fabric structure built up more slowly than with the Stoll. Both the Accelerotor and the Schiefer were more sensitive to differences in fiber toughness than was the Stoll. An imbalance between warp and filling yarn crimps had a much greater effect on the rate of damage and point of attack for the two flat abrasion testers than it had on Accelerotor abrasion. The tumbling action of the Accelerotor caused the greatest increases in fabric thickness by shaking fiber ends loose from the yarn structure and then cutting or breaking them off more slowly than did the Stoll abrader.