How to reduce mold cavity size?

From the difficulty of the work, it is much easier to consider the choice of repair welding and grinding on the movable mold than on the fixed mold.

Because the quality of the cavity surface of the fixed mold of the injection mold directly affects the appearance of the plastic part, and a large amount of heat is generated during the welding process, when there are no sufficient technological measures to guarantee, these heat often change the tissue composition of the cavity surface, resulting in the cavity surface Different hardnesses will affect the appearance of plastic parts. In practice, it is necessary to avoid modification of the cavity surface of the fixed model.

The general steps for modifying the cavity surface of a moving model are as follows:

1. Test the mold by pasting on the cavity surface, and roughly obtain the thickness that the cavity needs to increase or decrease.

2. Implement "repair welding" and "grinding" operations.

3. Try the mold again and adjust the size of the cavity surface according to the molding effect.

The second step is the difficulty and key. The following is the detailed process of cavity surface repair:

1. Select the welding material that matches the base material, determine the welding range, reserve and protect the grinding benchmark.

2. Alternate surfacing welding in sections, be careful not to weld from beginning to end, so as to avoid internal stress causing damage to the mold cavity surface.

3. Start grinding according to the reserved benchmark, and pay attention to the protection of the surrounding parts.

4. Measure the height of the repair welding surface. After meeting the requirements, fill the reference space to complete the cavity surface modification.