Principal Mechanical Design Engineer

Principal Mechanical Engineer - Electric Motor Design

Location: Hethel Engineering Centre, Chapman Way, Hethel, Norfolk NR14 8FP (3 days a week onsite)

Type: Permanent, Full-Time (8:30am - 5:00pm, Monday to Friday)

Start Date: End May or early June

About the Role

Are you passionate about electric machine design and eager to lead the development of next-generation electric motors? Our client is seeking a Principal Mechanical Engineer to join our dynamic engineering team. You will be responsible for the mechanical design, thermal performance, and integration of electric motors within our innovative products, ensuring robust, manufacturable solutions from concept through to production.

Key Responsibilities

• Lead the mechanical design and integration of electric machines, including rotor construction, structural integrity, and housing design.
• Develop and validate thermal management strategies using air cooling.
• Own the design and integration of key motor components (permanent magnets, flux paths, stator windings, insulation systems).
• Integrate speed, position, and temperature sensing solutions.
• Collaborate with electromagnetic and control teams to translate performance targets into practical designs.
• Conduct and guide design analysis (mechanical stress, rotor dynamics, thermal behaviour, manufacturability).
• Lead failure analysis, FMEA, and risk mitigation activities.
• Define and execute test and validation plans for performance, durability, and thermal requirements.
• Review and interpret test results, driving design improvements.
• Ensure designs are suitable for manufacture and scale-up, considering assembly, tooling, materials, and cost.
• Support internal and customer-facing activities by clearly explaining design decisions and outcomes.

What We're Looking For

• Proven experience in electric machine design, with a strong focus on mechanical and thermal aspects.
• Experience designing rotor systems (magnet retention, high-speed operation) and stator construction.
• Hands-on experience with motor build, testing, and validation.
• Experience leading FMEA and failure analysis.
• Understanding of air-cooled thermal management.
• Experience working in multi-disciplinary engineering teams.
• Engineering degree or equivalent professional accreditation.
• Strong knowledge of materials used in electric machines (electrical steel, magnets, conductors).
• Proficiency with mechanical and thermal analysis tools.
• Ability to balance performance, durability, manufacturability, and cost.
• Excellent communication skills and structured, evidence-based decision-making.
• Willingness to travel as required.

If you are interested in the above role then you can apply today 

Randstad Technologies Ltd is a leading specialist recruitment business for the IT & Engineering industries. Please note that due to a high level of applications, we can only respond to applicants whose skills & qualifications are suitable for this position. No terminology in this advert is intended to discriminate against any of the protected characteristics that fall under the Equality Act 2010. For the purposes of the Conduct Regulations 2003, when advertising permanent vacancies we are acting as an Employment Agency, and when advertising temporary/contract vacancies we are acting as an Employment Business.