WORKING PRINCIPLE

• A circular test specimen is passed over a friction surface comprising the same fabric or, when relevant, a wool abradant fabric, at a defined force in the form of a Lissajous figure, with the test specimen able to rotate easily around an axis through its centre, perpendicular to the plane of the test specimen. Fuzzing and pilling are assessed visually after defined stages of rub testing.

• The test apparatus consists of a base plate carrying the pilling tables and drive mechanism. The drive mechanism consists of two outer drives and an inner drive which cause the specimen holder guide plate to trace.

• The movement changes from a circle to gradually narrowing ellipses, until it becomes a straight line, from which progressively widening ellipses develop in a diagonally opposite direction before the pattern is repeated.

• The specimen holder guide plate is fitted with bearing housings and low friction bearings which carry the specimen holder guide spindles.

• The specimen holder consists of a body, specimen holder ring and optional loading weight.

• The apparatus is fitted with a pre-settable counting device which measures each revolution of one of the outer drives.