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The pencil hardness scale is commonly used to assess paint film hardness by checking what is the softest pencil that can mar the surface when you scratch it wit
by buildsjets 2mo ago
The pencil hardness scale is commonly used to assess paint film hardness by checking what is the softest pencil that can mar the surface when you scratch it with a given force. In this case, we needed to assess whether exposure to a certain chemical degraded the integrity of the paint coating that we were counting on for corrosion protection.