A part can look perfect in CAD software, but when it comes to real-world moulding conditions issues can arise as a result of design oversights that clash with the injection moulding process.
Injection moulding DFM (Design for Manufacture) is a helpful process that helps to minimise issues prior to manufacture is. A thorough DFM review assesses how successfully a part can be moulded.
Identifying potential issues at an early stage allows changes to be made while it is still straightforward and inexpensive, rather than discovering issues once expensive steel has been cut.
What does an injection moulding DFM review involve?
Injection moulding DFM is a process of evaluating a part from a manufacturing perspective. Considering how a part will behave throughout the injection moulding process is crucial over focusing solely on how the finished component should look and function.
A DFM review typically considers the following areas:
- Part geometry
- Draft angles
- Wall thickness
- Undercuts
- Material selection
- Gate positions
- Ejection
- Potential for sink marks and warpage
Each of those factors has an influence across the total moulding process, from how a component fills, cools and eventually ejects from the mould.
Our team of experienced engineers assess parts using CAD data, prototypes as well as using engineering software that helps us analyse how a design performs under moulding conditions.
What can change after a DFM review?
A DFM process helps us recommend changes to a part design for better manufacturability and in some cases, reducing part cost by omitting unnecessary features.
Recommendations can range from being relatively minor, such as an increased draft angle or a wall section adjusted. Other considerations have a greater impact on the mould itself, such as determining gate positions, parting lines and whether features such as slides or lifters are required.
Material selection also impacts how a part is moulded. Different polymers have different properties which affect flow, shrinkage and performance characteristics. The intended production material will also be considered alongside part geometry.
Why does DFM in injection moulding matter?
Some of the largest issues we have encountered in injection moulding projects have been the direct result of design oversights that weren’t identified before manufacture began.
Injection mould tools are a significant investment, and once steel is cut, it becomes difficult and costly to make substantial changes to the tool. Whereas changing a CAD model before tool manufacture is much simpler.
A thorough injection moulding DFM review helps reduce risk before committing to tooling. An experienced engineering team identify potential issues and recommend improvements to ensure a design is ready to progress into manufacture.
Can DFM reduce unnecessary costs?
In addition to identifying risks, a thorough review can also identify opportunities to simplify the way a component is manufactured. In some cases, we have been able to help customers remove unnecessary features or adjust their designs to achieve the same function with a simpler tooling solution.
Depending on the component, improvements identified during DFM can therefore contribute to lower tooling costs and more efficient production.
Conclusion
Injection moulding DFM provides greater confidence before making an investment in a mould tool. Identifying potential problems at the design stage means changes can be made painlessly.
Ultimately, the aim is to enter tool manufacture with a part design that has been properly considered from both a functional and manufacturing perspective.
At Liondell, manufacturability is considered from the beginning of a tooling project. Our complimentary initial engineering review allows us to identify areas that may require further consideration before progressing into a full DFM and tool manufacture.
Have a part you’re considering taking into production? Get in touch for a free tooling quotation and complimentary initial engineering review.
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