From Prototype to Injection Moulding

Torc Case Study

Case Study – Cric Insert


To convert an existing anatomical model from a prototype in to an injection moulded component.

The client supplied cad drawings of the existing airway model. However these drawings would need to be developed significantly to become a replaceable injection moulded part.


Using cad we drew up a number of iterations incorporating as many of the potentially required features that we thought would be needed to make the part. The CAD was then high grade 3D printed to become a physical part.

We tested this part and made some alterations to the physical 3D printed part. As the final part needed to be made of soft rubber we created a silicone mould and used our in-house vacuum casting to create a multiple rubber parts for testing. The vacuum casting process creates parts that exactly replicate what will be produced by injection moulding.


We then tested the rubber part. We trialled various changes to the physical component until it the component gave a true to life feed back to the user. This modified physical model was then re-drawn in CAD and another 3D model printed. Again we created test parts from this 3D print which were used in field trials. Based on feedback from the trials further changes were made.

Having created the exact part we need to be injection moulded we sent the CAD and some sample parts we had made to the injection mould tooling company. They said the part could not be made using the injection moulding process and that it would need to be redesigned. As we knew that the model we created in its current form was the best solution we pushed to have the tool created.