(1) The substrate treatment is not satisfactory, for example, the moisture content of wood is high, or the rosin and aromatic oil contained in wood itself are not removed, resulting in foaming when it naturally volatilizes.
(2) When the oily or water-based putty is not completely dried or the bottom coating is not dried, the top coating shall be painted.
(3) The seams and holes of wood are not filled, but there are gaps and holes.
(4) The paint viscosity is too high.
(5) The paint ratio is not appropriate.
(6) When brushing your teeth, drag the brush back and forth, and the bubbles generated are not eliminated.
(7) Oil stains, dust, blisters, etc. Attached to the surface of the substrate, and there is moisture around these impurities.
(8) There is water in the compressor and air pipe, or water splashes on the construction surface.
(9) Most of them are caused by pinholes.