ASTM D523:14 pdf free download – Standard Test Method for Specular Gloss.
leave a film.) Rinse standards in hot running water (temperature near 150°F (65°C)) to remove detergent solution, followed by a final rinse Do 1101 wipe standards. The polished black glass high-gloss standard may be dabbed gently with a lint-free paper towel or othcr lint-free absorbent material. Place the rinsed standards in a warm ovcn to dry.
8. Preparation and Selection of Test Specimens
8.1 This test method does not cover preparation techniques. Whenever a Lest for gloss requires the preparation 01’ test specimens. USC the procedures given in Practice D823.
NOTh 3—To determine the maximum gloss obtainable from a test material, such as a paint or varnish, use MethIs B or C of Practice D823.
8.2 Select specimens in accordance with Practice D3964.
9. Instrument Calibration
9.1 Operate the glossmeter in accordance with the manufacturer’s instructions.
9.2 Verify the instrument zero by placing a black cavity in the specified position. If the reading is not within ±0. I of zero, subtract it algebraically from subsequent readings or adjust the instrument to read zero.
9.3 Calibrate the instrument at the start and completion of every period of glossmeter operation, and during the operation at sufficiently frequent intervals to assure that the instrument response is practically constant. To calibrate, adjust the instrument to read correctly the gloss of a highly polished standard, properly positioned and oriented, and then read the gloss of a working standard in the mid-gloss range. If the instrument reading for the second standard does not agree within one unit of its assigned values, check cleanliness and repeat. If the instrument reading for the second standard still does not agree within OflC unit of its assigned value, repeat with another mid-range standard. if the disparity is still more than one unit, do not use the instrument without readjustment. preferably by the manufacturer.
10. Procedure
10.1 Position each specimen in turn bcneath (or on) the glossmeter. For specimens with brush marks or similar texture effects, place them in such a way that the directions of the marks arc parallel to the plane of the axes of the incident and reflected beams.
10.2 Take at least three readings on a 3 by 6-in. (75 by
150-mm) area of the test specimen. If the range is greater than two gloss units, take additional readings and calculate the mean after discarding divergent results as in the section on Test for Outliers of Practice D3980. For larger specimens, take a proportionately greater number of readings. For non-ideal samples. (for example, weathered samples) the parties involved shall determine the acceptable range.