The tests as given below can be used to arrive at a preliminary conclusion. Definitive conclusions must be drawn by the standard test methods.
Difference between carded and combed yarns (Or woollen and worsted yarns) of the same count
Untwist the yarn and note the arrangement in the fibers. In carded yarns, the fibers are spread unevenly across the length. In combed yarn, they will lie parallel to the yarn surface. Similar test can be done to distinguish between woollen and worsted yarns.
Closeness of the Weave
Hold the cloth to the light and look through it. It can be determined to find if the weave is loose or close. It can also give you an idea about the uniformity of yarns.
Also run your thumbnail diagonally across the cloth. Any loose weave will manifest itself in the form of pathway made across the cloth after the thumbnail.
Elasticity
Crumple the fabric and note the behavior when the pressure is removed. The fabric should spring back to its former shape quickly.
Starch
Rub the fabric together, starch will come out in the form of dust. Or tear the fabric, dust will fly.
Strength
Grasp the cloth in both hands about an inch apart and pull steadily.
Drape
Just spread the fabric over a surface so that it hangs down all around it and note the drape.
Colorfastness to Washing and Rubbing
Simply wash it or rub with a cloth.
Fastness to spotting- Used for Silk
Sprinkle a drop of water with little lime added to it. Allow it to dry then brush off.
Strain Resistance on Seam
Push the warp and weft with the finger nails, if they are pushed easily, the material will fray at seam. Another way to teat is to weave a needle in and out of the double of the material as if making a tuck. the Single cloth is then drawn away from each side of the needle and if a row of holes shows clearly alongside of the needle the material will not bear a strain.
Fastness to Perspiration
To test the change of color, dip it in a little warm vinegar and drying between tissue papers without rinsing.
Burn test methods to detect fiber composition are covered elsewhere in this blog.
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