What’s New in Plastics

One of the primary design rules to follow when designing injection moulded plastic parts is to maintain uniform wall thickness.  That’s because uniform wall thickness leads to parts that fill with more uniform filling patterns and more uniform pressure, temperature, shear stress and shrinkage distributions.  All of that leads to higher quality moulded parts that are less likely to warp or deform out of shape after they are ejected from the mould.

In addition, plastic parts with non-uniform wall thickness – or with significant variations in wall thickness – may be very difficult to fill and pack and could have defects such as short shots, sink marks and vacuum voids. And relatively thick sections with longer cooling times will dictate and increase the overall cycle time, causing an increase in manufacturing costs.

All of that is why one of my favourite new features of SOLIDWORKS Plastics 2015 is the Nominal Wall Thickness Advisor, which allows a user to determine the nominal wall thickness and view the percentage differences from nominal.  This new tool can then be used as a guide to help the user design better plastic parts that have more uniform wall thickness that are easier to manufacture and of higher quality.

Easily review variations in plastics part wall thickness with the new Nominal Wall Thickness Advisor

One of the reasons we developed this feature was to provide our users with a quick and simple way to help ensure they were designing plastic parts that would be easy to manufacture. And based on the results of recent a market survey, we found that over 60% of respondents required two or more rounds of mould rework before their moulds would produce acceptable quality parts (see figure). The good news is that our new Nominal Wall Thickness Advisor will also help users “design-in” higher quality so they can reduce or eliminate the number of rounds of costly and time-consuming mould rework required before producing good parts.