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TAPPI T 411 Caliper






Thickness (caliper) of paper, paperboard, and
combined board


TAPPI T 411 Caliper describes the procedure for measuring single-sheet thickness and variations in single sheet thickness of paper, paperboard, and combined board. The term “combined board” encompasses both corrugated and solid fiberboard. Because of the method of selecting samples longer in the cross machine direction for thickness profile measurements, the results will always be biased in that direction. Because of the relatively high pressure 50 kPa (7.3 psi) used in this test method, it may not be suitable for measurement of tissue or other soft or low density materials, because the structure may collapse (decrease in thickness) at the prescribed pressure of 50 kPa. An essentially identical method is described in ASTM D 645.


This method involves measuring the thickness of a single sheet of paper, paperboard, or combined board by the use of an automatically operated micrometer when a specified static load is applied for a minimum specified time.


Thickness is an important property of paper, paperboard, or combined board, and variations in thickness are also important especially for papers and paperboards used for mechanical purposes. This test is useful for research work, routine control, design of end-use products, and for acceptance testing for conformance to specifications. Thickness is one of the important characteristics that affects flexural stiffness.


Please note:
SGS-IPS cannot sell or otherwise provide standards, specifications, or test procedures to third parties.