DuPont Plastic Design Guide

The DuPont Plastic Design Guide: 10 Top Tips

The DuPont Plastic Design Guide focuses on helping users with technically effective design, properties that support material specification, and effective manufacturing techniques.

Here are ten tips for accomplishing behind-the-scenes tasks that help make successful, innovations through collaboration possible.

Tip 1:

Maximize Metal Replacement

Replacing metal parts with plastic is rarely a one-to-one process. Embracing design modification is not just a fact of life, it’s a potentially a huge advantage. Designing to plastic’s strengths opens opportunities for possible integration of functions, simplification, cost-efficiency and innovative design.

Plastic is Not Metal 

Tip 2:

Materials Matter

There’s no such thing as a bad material. But there are plenty of wrong materials for a particular application, and making one wrong choice can be costly and time-consuming. To choose the right materials, it’s imperative to know different material options inside and out, from properties to performance testing.

The Right Choice

Tip 3:

Make Walls Measure Up

Finding the right wall thickness is a key design challenge in many components. It involves balancing lighter weight against functional strength and molding performance. There are multiple factors which are critical to design walls that will perform in use, including mold flow behavior, fiber orientation and correct functional thicknesses.

As Much as Necessary – As Little as Possible 

Tip 4:

Use Ribs for Rigidity

One way to overcome the problems that can arise with thick walls is by the addition of ribbing, which increases rigidity while allowing wall thickness to be reduced. Getting ribs right can improve strength and reduce weight, but it can be a process of trial-and-error to find the right rib dimensions, positioning and materials.

Optimum Rib Design 

Tip 5:

Get Gates Right

Choosing the right type of gating system and gate location can avoid processing problems. But gate location can also be an overlooked way to improve the quality of molded parts.

Correct Gate Location 

Tip 6:

Follow the Money

There are many production, mold-making and assembly options that can affect costs. It’s important to choose carefully, to take full advantage of the specific properties of the plastic materials you’re utilizing to design manufacturing cost-efficiency in from the start.

Low-Cost Designs 

Tip 7:

Find the Best Fit

Simple, rapid assembly of components can lead to significant production savings. Snap-fit, press-fit, threaded assemblies – each has its best practices, advantages and limits. Choosing the right one is a matter of knowing materials and function, and designing an assembly process to match.

The Best Assembly Techniques – Part I 

Tip 8:

Weld to Last

There are a number of welding choices for joining plastic parts.  Finding the optimum choice that addresses cost, strength and efficiency requires factoring in welding technologies, materials and the joint geometry for each application.

The Best Assembly Techniques – Part II 

Tip 9:

Match Tolerances With Budgets

Injection-molded parts can’t be produced to the same tolerances as machined ones, so it’s important to design accordingly. A key consideration is setting tolerances that will perform in the application, without  disrupting cost-effectiveness in production.

Hidden Cost Factors 

Tip 10:

Test Your Assumptions

Every application or improvement is unique. Your design checklist should cover everything from material performance parameters to prototyping, testing and finding new ways to innovate.

Some Guidelines