Is it necessary to always sand the surface between application of two different products?
We recommend to always sand the surface between applying two different products to ensure uniform surface roughness and adhesion of subsequent layers. The sanded surface should also be cleaned and degreased.
Why did the polyurethane topcoat become dull?
Possible causes
Too short time for evaporation of the thinner,
How to prevent
Maintain the right conditions for complete evaporation of the thinner,
How to remove
Mat the surface, degrease and apply the paint according to the rule (right conditions and thinning proportions)