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Designing for Mouldability: what you need to know

Designing plastic parts for mouldability has become very beneficial during rapid injection moulding, despite it commonly being used for traditional injection moulding. This ensures that speed and quality remain constant during manufacturing. 


What Is Rapid Injection Moulding?


Rapid injection moulding is a process in that leverages manufacturing automation. Firstly, CAD models are directly sent to the production floor. Mould milling will now begin, moulds are mainly fabricated from aluminium and not steel. This will allow for a faster and more cost-efficient tooling in comparison to traditional steel moulds.



Design Considerations:


It is important to consider design in every aspect of the plastic injection moulding process. You should carefully consider wall thickness, if your wall section is too thin, you could have issues in structural failure or poor insulation characteristics. If your wall section is too thick, you could be seeing visual defects or an overweight part. In most circumstances, a thin uniform wall with ribs is preferable over a thick wall.


Why is it important to consider Radii? Radii is an important aspect in relieving the stress in a part. You should tend to avoid sharp corners as these corners tend to stick in the mould as the part shrinks. As well as this you should note that resin flows more smoothly around corners that aren’t sharp. The internal radius should be externally matched to maintain a constant section.


An undercut is the area of a part that shadows another area of the part. This will create an interlock between the part and one or both mould halves. We recommend that you avoid undercuts. This is due to certain design techniques that can already achieve the same effect as an undercut without effecting the part.


For more information when it comes to selecting an ideal material for your part please contact our specialists today! We can also provide further details into what you need to know about designing for mouldability, view our Design Guidelines.


Added: 10 Apr 2018 12:51

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