high precision sample holder
The Martindale test apparatus is used for various textile surface testing such as abrasion resistance, Velcro test and pilling tendency. However, the test procedure or rather the comparability of the results showed some problems. Regardless of the Martindale apparatus’ year of manufacture, the repeatability of the test result should be on the first place.
The repeatability has been insufficient on the previous specimen holder as the Martindale specimen holder component was linked together through manual bolting. It became evident that specimens have been fixed differently onto the Martindale specimen holder depending on the examiner. Thus, torsion of the specimen might occur in the specimen holder which leads to a non-repeatability of the test results. During the Velcro test, the Velcro hooklets of the lower bottom of the Martindale specimen holder face different directions because of the torsion. Hereby non-comparable damage symptoms will be created.
Optimized Martindale specimen holder for DIN EN ISO 12947
The repeatability and thus the precision of the method DIN EN ISO 12947 and the modified Velcro test on Martindale for automotive upholstery fabrics with different measuring points and repeated tests, has been criticized for a long time by the experts of the VDA working group. imat-uve therefore revised the method and undertook the necessary technical optimizations of the Martindale apparatus. The new design of the "Martindale high precision sample holder" minimizes operator-dependent influences during preparation and clamping of the specimen or the Velcro which before negatively effected the repeatability of tests with the conventional Martindale specimen holder. Through a revised pressure mechanism these negative factors on the accuracy of the Martindale test are now drastically reduced and the precision of repeatability is improved well below ten percent.