GURLEY™ Cobb Sizing Testers have been manufactured by Gurley for over a half-century Represent an economical and practical means of determining liquid absorptiveness or resilience of treated and untreated papers, boards, fabrics and other sheet materials.
A critical component of this test is a solid stainless steel roller having a smooth face 20cm wide and weighing 10± .5 kg
Use of Roller
At exactly the end of the predetermined test period, place a second sheet of blotting paper on top of the sample and remove the surplus water or other liquid by moving the hand roller once forward and once back over the pad. Care should be taken not to exert downward force on the roller. Alternative methods of blotting, such as rubbing with a cloth, are not recommended as the amount of blotting is uneven and will affect the outcome. Fold the specimen after removing it from between the blotter sheets and reweigh to the nearest 0.01g. Subtract the conditioned weight of the specimen from its final weight and multiply the gain in grams by 100 to obtain the weight of liquid absorbed in grams per square meter. For the 25 or 10 sq. cm. cylinders, multiply by 400 or 1000 respectively, to obtain grams per square meter.