Custom PS Injection Molding Factory

① Simple and Symmetrical Design: To minimize warpage and distortion, keep the geometry of the part simple and symmetrical. Complex, asymmetrical shapes can cause uneven material distribution and cooling, leading to defects.

② Avoid Sharp Corners: Sharp corners and edges should be avoided as they can create stress concentration points that may lead to cracks or part failure. Use rounded corners and edges to distribute stress more evenly and improve part strength.

③ Radiusing and Filleting: Incorporating radii in corners or transitions between surfaces reduces stress concentrations and enhances the mold flow, improving both the durability and aesthetics of the part.

① Minimize Warpage: Place the gate strategically to ensure even filling of the mold, thereby minimizing warpage or distortion. Gates should be positioned in areas where material flow is uniform and allows for easy ejection.

② Optimal Positioning: Avoid placing the gate in areas that could cause excessive stress or affect the functionality of the part. Gate marks should be placed where they are least visible or impactful to the part’s design.

③ Ejection Considerations: Choose gate locations that facilitate smooth part ejection, reducing the risk of deformation or sticking.

① Consistency: A consistent wall thickness throughout the part is crucial to ensure even cooling and minimize warpage. Variations in wall thickness can lead to uneven cooling rates, causing sink marks, warping, or dimensional instability.

② Recommended Range: Wall thickness for PS injection molding typically ranges from 0.76 mm to 5.1 mm, with the optimal thickness being around 2-3 mm. For large parts, gradual transitions in thickness (not exceeding 25% difference) should be used to avoid defects.

③ Avoid Thin Walls: Thin walls can lead to deformation, while excessively thick walls may increase cycle times and material consumption. A minimum wall thickness of 0.5 mm is suggested for optimal results.

① Ease of Ejection: Draft angles are essential for part ejection. A draft angle of 1° to 2° is recommended for most surfaces. For textured surfaces or areas with more intricate designs, draft angles may need to be 3° to 5°.

② Surface Variations: Draft angle requirements vary based on the surface texture and orientation:

• Near-vertical surfaces: 0.5°
• Common surfaces: 1° to 2°
• Shutoff surfaces: 3° or more

③ Textured surfaces: 5° or more, depending on texture depth.

④ Avoid Over-Exaggeration: Draft angles greater than 2° may cause part distortion, leading to cosmetic and functional defects.

① Ribs for Strength: Use ribs to reinforce weak sections of the part. The rib thickness should be 50% to 60% of the wall thickness to avoid sink marks and maintain strength without increasing part weight.

② Boss Design: Ensure bosses are appropriately sized and placed to allow for proper assembly and structural integrity. Avoid using bosses that are too thin or too thick, as these can create warping issues.

③ Minimize Warpage: Proper placement of ribs and bosses can add stiffness and strength, but improper placement can lead to excessive warping or distortion.

① Hole Size: For easy assembly and part integrity, make holes slightly larger than the screw or pin used in the assembly. A minimum diameter of 1.5 mm is recommended to avoid stress concentrations.

② Avoid Small Holes: Holes that are too small can lead to part failure, especially if they are not aligned or manufactured to proper tolerances. Larger holes also facilitate easier mold filling and reduce stress concentration.

① Uniform Finish: Consistency in surface finish is crucial for both aesthetics and performance. The finish should be chosen based on the application. A smooth finish is often required for decorative parts, while textured finishes may be necessary for functional or grip applications.

② Avoid Extreme Roughness or Smoothness: An excessively rough or overly smooth surface finish can cause part failure or inconsistencies during molding and post-processing. Opt for a balanced, consistent surface texture to enhance the final product’s quality.

① Properties of PS: PS is ideal for applications requiring a smooth finish and relatively low cost. It is not suitable for parts requiring high strength or flexibility, as PS can be brittle.

② Consistency: Use consistent, high-quality PS throughout the part to ensure uniform material properties and minimize the risk of defects like warping and cracks.

① Mold Cooling: Ensure that the mold is designed for efficient cooling to maintain uniform temperature distribution. Cooling channels should be placed around thicker areas to speed up cooling and prevent warpage.

② Ejection System: The mold should be designed for easy part ejection, minimizing the risk of damage to the part during removal. Use ejector pins or other systems that reduce stress on the part.

③ Simplicity: Avoid overly complex or intricate mold designs, as they can increase production costs and cause warping issues.

① Cooling Efficiency: Proper cooling is essential for preventing defects like warping and ensuring uniform shrinkage. The cooling system should be designed to maintain a consistent temperature across the mold.

② Avoid Complexity: Complex cooling systems can lead to uneven cooling rates and contribute to warpage. Ensure that the system is optimized to achieve consistent cooling without unnecessary complexity.

① Shrinkage: PS typically shrinks between 0.2% and 0.8% during cooling, so this must be factored into mold design to maintain dimensional accuracy.

② Processing Parameters: PS requires careful control of the mold temperature and injection speed. The optimal mold temperature is around 40°C to 50°C, and the injection speed should be fast to accommodate PS’s low viscosity.

① Static Electricity: PS can accumulate static charges, attracting dust or particles. Depending on the application, surface treatments like antistatic coatings may be necessary.

② Environmental Factors: Consider the end-use environment of the part (e.g., exposure to UV light, chemicals, or heat), as PS may degrade in certain conditions.