FFE Talentum TT2

The Challenges of Injection Moulding for Low Production Volumes

Summary

This article explores how Round Peg successfully developed an injection moulded product for lower production volumes by adapting off-the-shelf parts. The final device not only met stringent functional requirements and achieved IP54 compliance, but also streamlined assembly and maintenance procedures.

Introduction 

FFE approached Round Peg to lead the mechanical design side for a comprehensive overhaul of their Talentum Test Torch. Redesign of the internal electronics presented an opportunity to repackage the product, shifting to a more consumer-centric design.

Original Test Torch Product (Left) compared to the Talentum TT2 (Right).

Our Strategy

FFE’s requirement for a user-friendly, stylised design prompted Round Peg to explore using injection moulded components. However, the projected low production volumes posed a challenge as injection moulding is capital-intensive and more suited to higher volumes.

To ensure no compromises to aesthetics or functionality, we adopted an approach of sourcing an off-the-shelf injection moulded product that could be tailored to meet FFE’s specific design needs. This approach had previously been successful in adding complexity without the burden of upfront tooling and development costs, making it well-suited for lower production volumes.

Our Development Work

Initial work included identifying specific user requirements set by FFE for the final device, including user-friendliness, comfortable handling and IP54 sealing for harsh environment usage.

FFE collaborated with Round Peg to source a suitable casework from an existing thermal imaging device. A non-negotiable search criterion was securing rights-of-use and guaranteed supply for the product lifetime, which FFE was able to successfully negotiate with the manufacturer.

The selected casework consisted of four moulded components, featuring elements which would have been costly to develop from scratch, including:

  • User-friendly push buttons
  • An ergonomic shape for handheld use
  • An over-moulded soft hand grip

The casework required further internal space for all the optics and electronics, so our engineers designed an injection moulded two-piece extension, matching the design language of the original device.

To incorporate this extension, the casework was initially to be post-machined. As a bonus, the OEM agreed to modify existing tooling for one of the mouldings, eliminating this machining step and further streamlining assembly.

An off-the-shelf thermal imaging device (Left) was used as a starting point, to save on cost of injection mould tooling development.

Further Design

To achieve an IP54 ingress protection rating, materials research ensured the O-rings could handle the anticipated high internal temperatures and a custom gasket was designed for an existing interface that could not be modified to support an O-ring.

Efficient packaging remained crucial, despite the addition of the moulded extension. We addressed this by designing a custom heat sink which performed the dual function of mounting the optics and dealing with the thermal load.

We also considered ease of maintenance, with front access for simple bulb replacements.

As the design progressed, design for manufacture (DFM) was at the forefront of the considerations, resulting in a product that could be manufactured with the least possible tooling, documentation and training requirements. Vital for quality control!

Developing an injection moulded extension to the base device allowed for efficient packaging of optics.

Prototyping

Using our well-established network of local vendors, we produced several representative prototypes for testing. These used many techniques including:

  • In-house FDM printing, for rapid and low-cost manufacture of mock-ups.
  • In-house laser cutting of prototype gaskets.
  • CNC machining of internals, such as heat sinks.
  • SLA printing and vacuum casting, for a small batch of beta test devices.

As well as providing FFE with suitable suppliers for mass production. We also produced a set of jigs and fixtures to streamline the assembly process.

Conclusion

The final product achieved a more user-friendly design with improved functionality, while only requiring development of new injection mould tools for two of the six plastic components. This significantly reduced the overall development cost.

Following successful testing, the Talentum TT2 has entered volume manufacture, marking a successful collaboration between Round Peg and FFE.

For more information, please see https://ffeuk.com/talentumtt2/