Vacuum forming is a highly capable process, but like any manufacturing technique, it works best when parts are designed with the process in mind. At Jabro Games, we work closely with designers and product developers to optimise their designs for successful vacuum forming — saving time, reducing tooling costs, and improving the quality of the finished part.
Draft Angles Are Essential
Draft angles — a slight taper on vertical walls — allow the formed part to release cleanly from the mould without tearing or distortion. As a general rule, a minimum draft angle of two to three degrees should be incorporated on all vertical surfaces. Parts with zero draft are very difficult to demould reliably.
Avoid Deep Draws Where Possible
The ratio of depth to width in a vacuum formed part — known as the draw ratio — affects wall thickness consistency. Deep draws thin the material as it stretches, which can result in weakness at the base of the part. Where deep forms are required, material selection and sheet thickness need to be carefully considered.
Radius Internal Corners
Sharp internal corners create stress concentrations during forming and can cause the material to tear. Incorporating generous radii on internal corners improves the forming quality and the structural integrity of the finished part.
Consider Undercuts Carefully
Undercuts — features that would prevent the part from releasing from a rigid tool — are not achievable with standard vacuum forming. Designs with essential undercuts may require split tooling or post-forming trimming to achieve the desired geometry.
Our team at Jabro Games reviews all designs before tooling commences and will advise on any modifications that would improve formability or reduce costs. Get in touch at jabrogames.com.