Caution for operation of plaster 1:

1.石膏粉与水调合后，若发现水粉比例不合适时，应重取量调和。

1. After mixing gypsum powder with water, if the proportion of water powder is found to be inappropriate, the amount of gypsum powder should be reconciled.

2.搅拌的速度不宜过快，以免人为带入气泡，形成过多的结晶中心，导致石膏膨胀，强度降低。

2. The stirring speed should not be too fast, in order to avoid the artificial introduction of bubbles, forming too many crystallization centers, resulting in gypsum expansion and strength reduction.

3灌注模型时应从一侧逐渐到另一侧，震荡灌注，排除气泡，注满各细微部分。

3. The filling model should be gradually from one side to the other, shaking filling, eliminating bubbles and filling the fine parts.

4石膏在凝固过程中存在体积膨胀

4. Volume expansion of gypsum during solidification

影响熟石膏凝固速度的因素有熟石膏粉的质量、熟石膏粉与水调合的比例不当、搅拌的时间和速度、水温。

The factors affecting the solidification rate of ripe gypsum include the quality of ripe gypsum powder, improper mixing ratio of ripe gypsum powder to water, mixing time and speed, and water temperature.

5可以用建筑胶水调制。另则，也可以用免胶石膏粉，用水直接调制即可

5 can be modulated with building glue. On the other hand, it can also be made with glue-free gypsum powder, which can be directly mixed with water.

6水、石膏粉的混合比，水越多石膏凝固的时间越长，石膏密度越低；相反，水越多凝固时间越短，密度越大，牢度越高。水、石膏粉的混合比需要根据具体使用需求来控制

6. The mixing ratio of water and gypsum powder, the more water, the longer the solidification time of gypsum, the lower the density of gypsum; on the contrary, the more water, the shorter the solidification time, the higher the density and the higher the fastness. The mixing ratio of water and gypsum powder needs to be controlled according to the specific use requirements.

7搅拌时间越长，石膏凝固时间越快。一般而言搅拌到石膏粉非常均匀就可以浇铸了，通常将搅拌时间控制在5分钟内。浇铸容器与石膏粉凝固时间的关系。浇铸容器吸水与否影响着凝固时间，浇铸容器不吸水铸型凝固时间不变，反之，浇铸入吸水容器内，凝固时间缩短。

7. The longer the stirring time is, the faster the solidification time of gypsum is. Generally speaking, it can be cast by stirring until the gypsum powder is very uniform, and the stirring time is usually controlled within 5 minutes. The relationship between casting vessel and solidification time of gypsum powder. Whether the casting vessel absorbs water or not affects the solidification time. The solidification time of the non-absorbent casting mould of the casting vessel remains unchanged. On the contrary, the solidification time is shortened when the casting vessel is poured into the absorbent vessel.