Sustainable Infrastructure Ltd is a business built around three core areas of success:

➡️Major UK Infrastructure Projects
We operate as a trusted contractor supplier, partnering with clients across the UK to deliver safe, sustainable, and technically robust infrastructure staffing solutions. SI are active on Sizewell C, HS2, Havant Thicket, National Highways and other major infra projects. 

➡️Data Centre Recruitment Across Europe
Our team supports the full PMO skill set within the fast-growing data centre sector, connecting specialist talent with high-performance projects and helping clients scale efficiently. Personnel placed in UK, Ireland, Finland, Sweden, Netherlands, Belgium and Poland. 

➡️Technical Engineering for UK Start-Ups
We collaborate with innovative, high-growth UK start-ups, providing access to the technical engineering expertise they need to accelerate product development, strengthen their teams, and move from concept to execution.

Sustainable Infrastructure Ltd

Building a sustainable infrastructure starts with your people

Mechanical Design Engineer - Contract - 6-9 Months, outside IR35 - Remote. 3 days per week.
About the Company
We are looking for a Mechanical Design Engineer to lead the mechanical design of our next-generation variant and to take a leading role in mechanical engineering across our wider product portfolio. The headline project is a new form-factor variant of using the same core technology. You will own this design end-to-end: concept, detailed design, prototyping, validation, and handover to manufacture. Alongside this you will improve the existing product line and contribute to the technical direction of the company as it grows. You will report to the CTO and be the senior mechanical engineer on the team. A graduate mechanical engineer is already in post and will work alongside you on smaller projects and as design support.
My client is a technically rigorous start-up at the point where engineering decisions still move the company. As the mechanical design engineer on the team, you will own the design of the next product and have a direct hand in how the discipline grows. You will see your work installed in real buildings with measurable customer outcomes.
About the Role
What you will do
Lead the design of the new product variant from concept through to manufacturing handover, owning the mechanical design decisions and trade-offs throughout.Drive precision motion improvements - investigate linear bearing solutions that reduce acoustic noise while preserving precision and low friction; design and integrate the motor / bearing / mass assembly.Run finite element analyses - modal, structural, fatigue, etc as required using SolidWorks Simulation to validate designs before prototyping.Produce engineering documentation - design reports, drawings, simulation reports, test plans, and the technical documentation needed for compliance and for the wider team.Improve the existing product - cost, manufacturability, reliability, and noise performance.Support and mentor our other team members on day-to-day design work.
Qualifications
We expect at least 5 years of post-degree experience designing electromechanical or precision-motion products that have made it into production. The specific domain matters less than the discipline; strong candidates from robotics, industrial automation, semiconductor precision motion, medical devices, aerospace mechanisms or similar fields are very welcome. Prior vibration or dynamics experience is not required.
Required Skills
Degree in mechanical engineering or a closely related discipline.Proven track record taking electromechanical products from concept to manufacture, with examples you can talk through.Strong SolidWorks and SolidWorks Simulation skills, including FEA for structural, modal and fatigue analysis.Comfortable owning design decisions, trade-offs, and the technical documentation that goes with them.Hands-on instincts - happy to prototype, test, measure, and iterate, not only design at the screen.Excellent written and verbal communication; the role involves producing reports and working closely with the team and external stakeholders.Existing right to work in the UK. Visa sponsorship will be considered only on an exceptional basis.
Preferred Skills
Experience designing for linear motors, voice coils, or other direct-drive actuators.Working knowledge of linear bearings, flexures, or other precision guidance systems, particularly where acoustic noise is a constraint.Experience driving products through CE / UKCA marking and mechanical safety standards.Familiarity with DFM, supplier qualification and the transition from prototype to volume production.Chartered status (CEng) or working towards it.
Mechanical Design Engineer - Contract - 6-9 Months, outside IR35 - Remote.