Gurley Cobb Tester

The Cobb Sizing Tester provides an economical and practical means of determining liquid absorptiveness

or resilience of treated and untreated papers, boards, fabrics and other sheet material. It can be used with

a variety of liquids including water, oil, ink, and water based solutions.

The complete kit consists of the Cobb test apparatus, a 10 kg roller and a supply of blotting paper. The

roller method is recommended to ensure better consistency and reliability then manually blotting or

rubbing the specimen.

Test Method

The Cobb Sizing Tester consists of a hollow metal cylinder, a metal base plate, a clamping device to hold the

ring against the sample and a neoprene mat to ensure a tight seal.

A 12.5 cm x 12.5 cm test sample is weighed and then placed on the neoprene mat and clamped. Pure the

test liquid (100ml for 100 sq. cm cylinder) and start timing the test immediately (test duration typically 120

seconds).

At 15 seconds prior to test completion, remove the liquid from the cylinder, unclamp the sample, quickly remove

the ring and place the sample (wetted side up) on a sheet of blotting paper. At the exact end of the test

period place a second sheet of blotting paper on top of the sample and remove excess liquid by moving the

hand roller once forward and backward over the sample. The sample is now reweighed to obtain the weight

of liquid absorbed.

Features:

         Metal Ring: 100, 25 or 10 cm2

         Roller: 20 cm wide face

         Roller Weight: 10.0 + 0.5 kg