Warp test

Ten warps, 10 wefts per batch Visit twice per annum, removal of a 2m wide piece at a random interface, 10 warp tests, 10 weft tests... 

Another thermal consideration concerns warp temperature, the temperature at which a material begins to distort. A test for it can be performed either on the product itself or test specimens. It is somewhat subjective, since the definition of failure with this test usually varies for each application. However, the test can be useful, since it attempts to duplicate actual conditions of use. In a warp test it is important to note not only the... 

A hairdryer and a can of HFC-134a ( Freon ) can help do quick temperature testing. But if you decide to put the board in a temperature-controlled oven, you should be aware that normal scope probes can melt or warp under extremes. Also choose your cables carefully (try Teflon-coated ones). Teflon cables can be very brittle, however. 

Tensile Testing. Tensile tests were run on an Instron 1000 using a 5.08 cm (2 Inch) guage length and a speed of 12.7 cm (5 lnches)/mln. The procedures In Burlington Test Procedure FP-015 (ASTM-D-579) were followed. At least 5 specimens of each sample were tested. Fabric tests results are quoted for the warp direction only. The percent retention of tensile strength was calculated from the equation % retention where F and F(j are the... 

Materials. The modern silk fabric tested was Testfabrics style 607 broadcloth, degummed but undyed and unbleached. The fabric yarn was 140/2 cotton count and the warp and filling threads/0.01 m are 40 and 33, respectively. Fabric weight was approximately 56 gm/m. ... 

Initial Characterization. Modern silk was subjected to tensile testing to evaluate the test procedure to be used, the number of samples required and the expected precision. Five fabric samples tested in the warp direction were found to give a coefficient of variation of less than 5% for breaking-load and less than 10% for strain-to-break. 

Normally, the first step in textile conservation is the examination of the piece to determine the fibers from which it was made and the technique by which it was created. One determines the spin of the yarns, whether Z or S, and the number of wefts and warps per inch. Next, one tests for colorfastness first with distilled water, then with glycerin and water, and finally with a neutral detergent and water. If the colors run with any of these solutions, obviously the piece cannot be washed, and one tests with dry-cleaning solvents and other chemicals. 

Testing of Fabrics for Tensile Properties. Unexposed and exposed pieces of L-4 Blue Wool fabrics were tested in the warp and fill direction for tearing strength by ASTM Method D-1424 on an Elmendorf tester (11). 

To determine whether or not changes in color were accompanied by fiber damage, unexposed fabric and several fabrics exposed to the xenon-arc source for 550 kj/m2 (AE from 1 to 3) were tested for tearing strength by the Elmendorf method (11). Before exposure, the tearing strength of the blue wool fabric was 2040 g in the warp and 1710 g in the fill direction. For all other fabrics tested after exposure to light, the... 

Since introduction of bending moment is a concern, strain should be measured on more than one side of the specimen. This is necessitated by the fact that the specimens are heterogeneous and may be bent or warped as a result of the manufacturing or fabrication process, and cannot be corrected by machining or grinding due to other testing constraints. 

Samples and duplicate samples of unbleached desized cotton print cloth (400 V test fabrics), 80 X 80 count, 3.5 oz/yd2, and yarn size of 40 singles in warp and weft, were randomly selected after conditioning to 55% rh in a desiccator over potassium dichromate solution. The samples were placed inside the pharmacy bottles along the flat sides so that each bottle contained one sample and one duplicate. When the samples were placed side by side along the flat side of the bottle chambers, they filled the entire flat-sided area. Dark chambers were achieved by wrapping the bottles in aluminum foil to exclude light. 

---