DeMatia flex testers.

DeMattia flex testers are said to offer improved features and greater flexibility, according to company literature. Three versions are offered, holding 12.24 or 36 samples, and are available in an unheated cabinet or a temperature controlled oven (temperature range 60[degrees]C to 150[degrees]C). All models conform to a variety of standards, including ASTM, BS and ISO, according to the literature. The range of flexing machines is used to test specially molded samples for resistance to cracking or cut growth by repeated flexing. Flex testing is recommended when flexing encountered in service can be simulated by the action of the test, as for example in the sidewalls of tires or soles of shoes, according to the literature. Samples are prepared in accordance with the standard and then clamped into the grips. The grips are arranged in four banks, with two accessible from the front and two from the rear of the instrument. The bottom set of grips remains stationary during testing, while the top set reciprocates at a constant frequency for a pre-set number of cycles. Cracking and cut growth are evaluated at regular intervals. (Wallace Instruments, P.O. Box 4400. Copley, OH 44321-0400)

Circle 138 on card