0.3 mm thick sheets of impact resistant polyvinyl chloride were
cut to panel dimension of 15 · 10 cm. The edges were tabard
and the surface was roughed with sand paper to get suitable
roughness. The panels were coated delicately in front and back
with two successive coats of the prepared paints, allowed an
interval of 12 h between each coat. The coated panels were
connected to the testing cages with nylon threads thorough a
nail bored in the panel.