1.thickness is measured by placing the material between two plates.
2.usually one plate is on top of the other, and the top presser foot, applies a specified uniform weight.
3.the distance between the two plates is then determined (astm d 1777).
4.the presser foot that is used for most fabrics is 25-28 mm in diameter.
5.the thickness of materials varies with amount of pressure applied during the test. for this reason , the pressure should.
alway be apecified in reporting results and the test method includes a table re commended pressures for different type of fabrics.