Drying putty produces defects

Drying putty mainly refers to two kinds of amino putty and water quality putty. However, due to the good scraping performance and drying performance of amino putty , it is generally not suitable to produce defects during the construction process, and the defects are mainly caused by water quality putty. For the defects of water quality putty, bubbling, cracking, agglomeration, unsuitable for scraping, difficult to polish, and poor adhesion .

1. Bubbling

There are three main reasons for bubbling: First, the putty itself has poor high temperature resistance. If the filler used in the putty is too fine and dense, the moisture cannot evaporate in time after encountering high temperature and cause bubbling on the surface ; Moisture volatilizes rapidly and pushes up the surface layer, causing bubbling; third, the putty is loose in texture and easy to breathe, but the surface layer is too smooth to seal the inner layer, and the moisture in the inner layer evaporates rapidly after encountering high temperature, causing bubbling. To eradicate these phenomena, first, the baking temperature should be low and then high, so that the moisture in the inner layer is gradually volatilized, and then increase the temperature to dry, in case the initial baking temperature is too high, the surface layer will dry first and the inner layer will be moisture Aggregation lifts up the surface layer to cause bubbling; second, bake the putty in small samples before use, and it can be dried within the specified temperature and time (related equipment: oven) without bubbling, and then it is officially used.

2. Cracking

Reasons for analysis: First, the greasy layer is too thick at one time, but the bottom is not scraped solidly, and the greasy layer shrinks and cracks too much water is added when the putty is mixed, and it is baked at high temperature after scraping Rapid shrinkage causes cracking. Therefore, do not add too much water when mixing the putty , and scrape the bottom firmly when scraping, and at the same time, do not scrape too thickly at one time to prevent cracking.

3. Caking

The main reason is that the putty itself has poor storage properties and causes agglomeration. For this kind of defect, if the agglomeration is slight, you can add a small amount of water to fully mix it evenly; if the agglomeration is serious (hard block), it cannot be used to prevent quality defects or affect the construction.

4. Not suitable for scraping

The putty contains an excessively large proportion of binder, which causes excessive viscosity and is not suitable for scraping. Before use, add appropriate amount of filler and warm water to fully mix evenly, then it can be solved.

5. Difficult to polish

It is caused by the excessive proportion of binder in the putty. The solution is not suitable for scraping.

6. Poor adhesion

The amount of binder in the putty is too small or the amount of water added during deployment is caused. The solution is to increase the amount of adhesive and reduce the amount of water used during deployment, which can avoid