Flexible design outsourcing
End to end services
- CAD modelling, using Siemens NX
- Mechanical Engineering Design
- Electrical Engineering Design
- Design Engineering Project Management
- Plastic Injection Moulding Design
- Supplier Research
- Manufacturing Advice
- Prototyping & Product Feasibility
- Cost Estimation
- Product Design for Manufacture (DFM)
- Re-shoring
Ready to reduce risk and cut lead time?
We can communicate in either French or English.
Product design lifecycle
Plastic injection moulding design
High-performance parts. Tooling-ready precision.
We specialise in plastic injection moulded product design for clients who need more than just a pretty CAD model. At Convert Design, we deliver robust, production-ready part files optimised for tooling, performance and cost.
Our expertise includes:
- Optimising part geometry to prevent warping, sink marks and short shots
- Wall thickness consistency and material flow
- Ejection and split-line planning
- Gate positioning and undercut elimination
We work across high-performance sectors including automotive, marine, and environmental tech—where durability, heat resistance, and fluid dynamics are critical.
Our designs are created using Siemens NX, ensuring smooth integration with advanced tooling systems and compatibility with your manufacturer’s requirements.
💡 Frequently Asked Questions
Q: Can I convert my existing part from 3D printing to injection moulding?
A: Yes—but we often need to adapt wall thickness, draft angles and internal features to suit tooling processes.
Q: How tight should my tolerances be for injection moulded parts?
A: Over-specifying tolerances is a common issue. We help you balance cost and function with moulding-appropriate specs.
Q: Do I need to provide a STEP file or full production drawing?
A: We can work from sketches, legacy files or early CAD. We’ll create tooling-ready outputs from there.
Q: I have a CAD design already. Why would I need more before manufacture?
A: Many CAD files look good but lack the detail toolmakers need—leading to delays and costly rework. We use Siemens NX and draw on real toolmaking experience to deliver production-ready designs that work first time.
Q: What are the most costly design errors in plastic injection moulding?
A: i) draft angles, ii) inconsistent wall thickness, iii) overcomplicated geometry, iv) over-specification of tolerances, v) failing to consider material behaviour. We’ve compiled a pdf quick-fix checklist of these five most common – and costly – mistakes. Click here to access your free copy.
Want expert feedback on your part design?
“Not all plastic injection moulding companies can afford their own full time product designers. They need to outsource. And that’s where Convert Design step up. When we don’t have the time to do professional images ourselves for new business presentations, we’ve successfully collaborated with Convert Design who act as extended members of our team to present concepts to customers. We’re delighted how often those meetings have led to full design briefs.”
Glyn Olden, Managing Director, Chess Plastics.
Design for Manufacture (DFM)
Smarter product design. Built for real-world production.
At Convert Design, we believe great product ideas deserve manufacturing-ready execution. We specialise in Design for Manufacture (DFM)—optimising every aspect of your CAD model so it moves smoothly from screen to shop floor.
Our end-to-end approach combines deep engineering insight with practical manufacturing experience. We help clients avoid costly late-stage changes by factoring in:
- Wall thickness, draft angles, split lines, and ejection strategy
- Tolerances appropriate to your production process
- Tooling feasibility and material behaviour
Whether you’re designing a single-use plastic component or a critical part for automotive, aerospace or marine applications, we use Siemens NX and Finite Element Analysis (FEA) to simulate performance and simplify manufacture.
“We brought (Convert Design) in to take over a mechanical design job that had previously been taken to first prototype stage, but that was lacking in terms of what it needed to be usable for a real-world system…. refined the design and produced variants for three different manufacturing technologies to enable us to migrate to different manufacturing solutions as the product scales….work and approach are exemplary, participating fully ….contributing above and beyond expectations.“
Mike Callender – Klarian”
Prototyping & Product Feasibility
Test fast. Refine smart. Avoid expensive mistakes.
Before you commit to tooling, make sure your design can deliver in the real world. At Convert Design, we support clients with virtual and physical prototyping, helping you prove form, fit and function before investing in manufacture.
Our prototyping services include:
- Virtual design validation using CAD simulation and FEA
- Material and tolerance testing under simulated loads
- Low-volume physical prototyping, including 3D printing and machined parts
We help you answer essential questions early:
- Will it withstand heat, pressure, or drop impact?
- Will the geometry allow for clean ejection from a mould?
- Are we over- or under-engineering key features?
We’ll also help you compare your prototype process vs final production method, highlighting adjustments needed when transitioning from CNC or 3D printed samples to injection moulded production.
“It’s so important to avoid a costly retool with Convert Design’s early-stage review. Their prototype insights can save weeks, or even months.”
Need a second opinion before committing to tooling?
👉 Ask us to validate your design