Patent ID: 6925857

Claim:
A method of determining an average length of reinforcing fiber in a sample of reinforcing fibers, the method comprising steps of: weighing a sample of reinforcing fibers to obtain a total sample weight; placing the sample of reinforcing fibers in a fiber separating mechanism, the fiber separating mechanism comprising a screen section having a hollow cylinder with a predetermined height and a screen material extending across an inner diameter; suspending the sample of reinforcing fibers in water in the fiber separating mechanism; stirring the water so that the reinforcing fibers are substantially oriented in a plane that is substantially parallel to a plane defined by the screen material after which the water is allowed to settle such that the sample of reinforcing fiber addresses the screen material substantially along a length dimension of each reinforcing fiber and divides into a plurality of fractions in separate sections of the fiber separating mechanism, each fraction comprising reinforcing fibers having substantially similar lengths; weighing each of the plurality of fractions; and calculating an average fiber length from the relative weights of each of the plurality of fractions and the total sample weight.