Evaluation :-
Apply the Adhesive Tape over the lattice section, and within 5 minutes of application remove by pulling the free end steadily within 1 second at an angle as close as possible to 60°.
Carefully examine the cut area of the coating using the x3 Illuminated Magnifier. Classify the cut area according to the relevant National Standard classification guide.
The following classification guide is given as an approximate information guide only (refer to the appropriate National Standard for the precise classification):
ASTM 5B: The edges of the cuts are completely smooth. None of the squares of the lattice is cut.
ASTM 4B: Small flakes of the coating are detached at intersections. Less than 5% of the area is affected.
ASTM 3B: Small flakes of the coating are detached along the edges and at intersections of cuts. The area affected is 5% to 15% of the lattice.
ASTM 2B: The coating has flaked along the edges and on parts of the squares. The area affected is 15% to 35% of the lattice.
ASTM 1B: The coating has flaked along the edges of cuts in large ribbons and whole squares have detached. The area affected is 35% to 65% of the lattice.
ASTM 0B: Flaking and detachment worse than grade 1B.
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