Common CAD Design Mistakes to Avoid in Plastic Injection Moulding

Posted on: 07/04/2025

Category: News

Designing for plastic injection moulding can be a complex process, and even small errors in the initial CAD design can lead to costly consequences. Many businesses attempt to create their own designs without fully understanding the intricacies of moulding, resulting in defects, delays, and increased production costs.

By identifying and addressing these potential mistakes early, you can avoid unnecessary setbacks and ensure your product is optimised for efficient manufacturing. Engaging with experts at the design stage helps prevent these issues, allowing you to maintain quality, reduce costs, and bring your product to market faster.

What You Need to Look Out For

1. Inconsistent Wall Thickness

Variations in thickness can lead to issues such as warping, sink marks, and uneven cooling, which may affect the structural integrity of the final product.

Solution: Maintain uniform wall thickness throughout the design or ensure smooth transitions between sections to facilitate even cooling and reduce internal stresses.

2. Poorly Designed Ribs and Supports

Ribs are used to add strength to a plastic part without increasing wall thickness, however, poorly designed ribs can cause sink marks and stress concentrations.

Solution: Ensure rib thickness is around 50-60% of the main wall thickness to improve stress distribution.

3. Overly Sharp Corners

Sharp corners in a design creates stress points that can lead to cracking or weak spots in the final product.

Solution: Use radii instead of sharp angles to improve material flow and reduce stress concentrations.

How Expert CAD Designers Save You Time and Money

Do you want to avoid the mistakes mentioned above? Partnering with a skilled CAD designer is the solution.

With the support of a CAD design expert, you can refine your design before it reaches the moulding stage, helping you:

• Minimise defects and rework
• Reduce tooling modifications
• Speed up time to market
• Optimise material usage for cost efficiency

How Chess Plastics Can Help

At Chess Plastics, we offer expert support throughout the entire design and moulding process. Our team can transform your initial concept into a refined, production-ready design using industry-leading CAD software, ensuring smooth and efficient manufacturing. By partnering with us from the outset, you can achieve higher-quality results, minimise costs, and avoid unnecessary delays.

If you're developing a plastic component and want to optimise it for injection moulding, contact Chess Plastics today. Our expertise in CAD design and injection moulding can bring your ideas to life.