Designing for plastic injection molding is a complex process that requires careful consideration of several factors. This helps ensure the finished product is high quality, cost-effective, and manufacturable. The following are the top 10 most important things to keep in mind:

1. Material Options and Consequences

The specifications of the component and injection molding procedure should guide the selection of the material. Many material attributes — strength, flexibility, durability, and cost — affect the end product and the production process.

2. Critical Tolerances

Tolerances are the permissible deviation from the nominal dimension of a component. Critical tolerances must be met to guarantee that a component operates as intended. Therefore, critical tolerances should be carefully evaluated in a design for plastic injection molding to ensure they can be held throughout manufacture.

3. Sink Marks

Sink marks are surface depressions that can form on a component if the material cools and shrinks unevenly. Changes in wall thickness or the presence of thick and thin parts can also produce them. To eliminate these, the design should work well with injection molding, and the wall thickness should be consistent.

4. Steel Safe Areas

Steel safe areas are mold sections where the plastic cannot flow. They are required to avoid mold or component damage during the injection molding process. While designing for plastic injection molding, steel safe regions should be considered to ensure the design suits the mold and manufacturing process.

5. Gate Location

The gate is the entry point for plastic into the mold. The position of the entrance is a crucial factor in a design for plastic injection molding since it can affect mold fill and the end product. Therefore, the gate should be prepared, so the plastic flows uniformly into the mold, avoiding flaws and assuring constant filling.

6. Shut-Off Angles

Shut-off angles are the angles at which two mold surfaces meet. They are important to prevent flash or excess material from spilling out of the mold. When designing for plastic injection molding, shut-off angles should be considered to ensure that the part can be easily removed from the mold without damage.

7. Draft Angle Orientation

Draft angles are necessary for mold removal. They should be included in the component so that it may be withdrawn from the mold without causing harm to the part of the mold.

8. Texturing and Draft

Texturing is the addition of a pattern or texture to the surface of a component. It can be utilized to improve the aesthetics or grip of the element.

9. Scheduling of Critical Start-Up Phases

The start-up phases of the injection molding process are critical to ensuring that the final product is of high quality. Hence, scheduling critical start-up stages like material handling and mold temperature control optimizes manufacturing and ensures product uniformity.

10. Secondary Operations and Fixtures

Secondary procedures, such as machining or assembly, may be required to finish the final product. Fixtures may also be required to keep the item in place during the injection molding. Thus, these should be addressed in a design for plastic injection molding to ensure they don’t affect the process or component.

Integral Manufacturing: Your Reliable Partner for Plastic Injection Molding

Since 1987, Integral Manufacturing has provided high-quality, customer-specific contract manufacturing. In addition, WTTM, West Troy, and RK Metals offer additional production capabilities to meet various customer needs, including plastic injection molding. Contact us today, and we will gladly help you with your custom plastic injection molding needs!