Rosti’s collaboration with a leading Tier Supplier began in 2017 when they sought to expand and diversify its supplier base.

We have recently collaborated with them again to explore new moulding capabilities for its optical lens components and identified Rosti as a partner with proven expertise in hot runner injection moulding.

The project focused on developing a more sustainable and cost-efficient production method for a precision optical lens.

Our customer wanted to eliminate the significant runner waste created by traditional moulding methods and achieve cost savings, while maintaining the high optical quality required for their components. After 24 months of development, the project is now in full production.

Project Timeline

The journey began two years ago when Rosti North America were approached to explore alternative production methods for an optical lens.

Rosti’s engineering team first reverse-engineered the existing component, analysing the current production methods to understand the opportunity for improvement and the quality requirements of the part. With this insight, the team developed an optimised approach using hot runner injection moulding as a sustainable alternative to traditional cold runner techniques.

Throughout the development phase, Rosti’s cross-functional team – comprising Account Management, Engineering, Business Development, and Quality specialists, worked closely with Tooling Engineers, Supplier Quality Engineers, and Procurement team from our customer.

This strong collaboration ensured that every design decision and process adaptation aligned with both the Tier Supplier’s requirements.

The component has undergone qualification testing to confirm performance and manufacturing reliability before it progressed into full-scale production.

What are the challenges of injection moulding Optical Lens?

Historically, the optical lens was produced using traditional moulding methods that relied on a large plastic runner. This generated a significant volume of scrap that need to be disposed of and, ultimately, wasn’t good for the environment. Our customer was committed to reducing the environmental impact of production, so a more sustainable approach was essential.

Introducing hot runner technology into optical moulding was an ambitious step. Hot runner systems are rarely used for optical parts because of the extreme precision and clarity required.

To overcome this, Rosti utilised our global expertise and knowledge, consulting with internal specialists to confirm the feasibility of the design and to ensure the final solution would achieve the accuracy, optical quality, and structural integrity required.

Bespoke Hot Runner Injection Moulding

Our solution involved developing a customised hot runner injection moulding process specifically for the optical lens. The project began with a detailed design feasibility review, in which the team adapted the moulding process to meet the stringent optical and structural requirements.

This led to the creation of a dedicated tooling and moulding solution that eliminated the need for runners entirely.

We worked hand in hand with our customer to validate every stage of the process, from tooling design to prototype development. Extensive testing was undertaken to ensure that the lenses produced using this new method met the same, if not higher, performance and quality standards as those manufactured using traditional methods.

This approach allowed us to address challenges in real time and refine the solution into a production-ready process.

Sustainable Injection Moulding for Optical Lens

The outcome of this collaboration represents a significant step forward in sustainable manufacturing for optical components in the automotive industry. The change in production methods has resulted in a substantial material and cost saving.

The method has completely eliminated runner waste, which not only reduces plastic scrap but also lowers the associated disposal costs. By using less material overall, our customer achieves both cost-efficiency and environmental benefits.