Plastics:

(1) The mixing of new materials and recycled materials should be consistent.

(2) The drying conditions should be consistent and the particles should be uniform.

(3) The influence of shrinkage rate on dimensional accuracy is fully considered when selecting materials.

4. Processing:

(1) If the plastic processing temperature is too low, the temperature should be increased because the higher the temperature, the smaller the dimensional shrinkage.

(2) For crystalline plastics, the mold temperature is lower.

(3) The molding cycle should be stable and should not be excessively fluctuating.

(4) The amount of feed should be stable.