Check the surface:
Good panels should have clean and flat surface, there are no bubbles, dots, raised grain or scratch on the aluminum surface.
Thickness:
Check the thickness by slide calliper rule, the tolerance of panel thickness should not exceed 0.1mm, tolerance of aluminum thickness should not exceed 0.01mm
Core material:
Check core material by eyes, the material color should be average, there are no visible impurity.
Flexibility:
Bend the panel directly to check its flexibility. acp has two kinds: unbroken and broken, unbroken is more flexible and more expensive.
Coating:
The coating is divided into PE and PVDF. PVDF coating has better weather-resistance, and its color is more bright and vivid.
Size:
Tolerance of length and width should not exceed 2mm, diagonal tolerance should not exceed 3mm
Peeling Strength:
Try to peel the aluminum skin from the core material, use tensionmeter to test the peeling strength, the peeling strength should not under 5N/mm.