Finch Wet Strength Devices

Measure the tensile breaking strength of water-saturated paper and paperboard with the finch wet strength device.


The finch wet strength device is used to determine the wet tensile strength of a sample.

This information is important for materials subjected to moisture and stress during processing or use. It is particularly useful for measuring paper, paperboard and other materials that are easily damaged by handling when wet. 

This device consists of an open-ended horizontal bar that simplifies insertion of the sample and a vertically movable container that holds water or other liquid. The sample is wrapped around the bar and both ends are secured in the upper grip.  The operator raises the container to saturate the sample, and then the test is started. This device complies with TAPPI T456, ISO 3781, ISO 12625-5, ASTM D824.

The finch wet strength device is constructed of stainless steel which provides excellent resistance to rust and corrosion. It can be used with any tester with a grip capable of holding a 2.4 mm thick x 25.4 mm long tang for the 1” device or 1.6 mm thick X 76.2 mm long tang for the 3” device.

Available Sizes:

1” (731-0040)

3” (731-3000)

Additional information

List of Standards

TAPPI T456, ISO 3781, ISO 12625-5, ASTM D824

Part Number



Finch Wet Strength Device