The cause of the stucco gypsum foaming

Empty drum, foaming, the main reason is caused by the grassroots and paint layer between the gas, and why not according to the normal to the surface air diffusion and to grassroots internal diffusion, and in the middle, the main reason has the following several aspects:
1) grassroots mishandled, paint layer and the base contact close enough, formation of interlayer;
2) at the grass-roots level and paint layer between the dense layer spread the air can't normal to the grassroots.
Solution:
A, if the metope of bubble or empty drum is lesser, can through the way of polishing processing interface enhancer of the reoccupy after besmear to brush, then batch of scraping;
B, if metope empty drum is bigger, have already caused extensive loss, is recommended with interfacial strengthening agent after eradicating besmear to brush, then blow