Senior Mechanical Engineer - Linear Electromagnetic Machine

Menlo Park, CASalary$140k–$165kPosted Jul 14, 2026

About Mainspring

Mainspring Energy manufactures and delivers fuel-flexible, low-emissions local power solutions that rapidly add new capacity and deliver reliable, affordable, and sustainable electric power. The company began commercial shipments of its Mainspring Linear Generators in 2020 and today has hundreds of megawatts in advanced development and field operations for leading Fortune 500 companies, data centers, and utilities. Mainspring also partners with global energy leaders including AEP, NextEra Energy Resources, Schneider Electric, and more.

The core values that ground our work, guide our decisions, and connect us together:

Pragmatic Optimism
Excellence without Ego
Proactive Collaboration

About Mainspring

The core values that ground our work, guide our decisions, and connect us together:

Pragmatic Optimism
Excellence without Ego
Proactive Collaboration

Core Responsibilities

Lead and participate in brainstorming activities to develop novel ways to improve all aspects of the LEM and the Linear Generator broadly.
Develop and optimize key mechanical and electromechanical subsystems within the LEM to drive down cost, improve performance, and deliver high reliability. These systems may include: magnetic encoders and other position sensors; high-voltage wiring and coil design; precision-machined steel and cast-iron components; magnet array assembly methods; composite material manufacturing and analysis; air bearing design, development, and testing.
Lead failure analysis on assembly, parts and process utilizing engineering fundamentals to drive containment and corrective action
Engage with data collection, analysis and review to aid in team, project and company level decision making.
Work with reliability and test teams to validate systems and components with fast cycles of learning for deployment into the next generation of Linear Generators.
Collaborate cross-functionally with manufacturing engineering, NPI, and external suppliers to rapidly deploy new designs into production.
Stay current on mechanical engineering advancements relevant to power generation, identifying opportunities to reduce costs, improve performance, and enhance reliability as Mainspring scales its technology
Uphold and further Mainspring's mission to create clean, affordable, and reliable power generators that accelerate the world's transition to a sustainable energy future

Qualifications

Bachelor's or Master's degree in Mechanical Engineering or similar field.
6+ years as a professional mechanical design engineer.
Deep understanding of metal castings, machining, welding/fabrication, bolted connections, datum selection, large tolerance stackup analysis, and finishing processes with the ability to identify and resolve design for manufacturability issues.
Proficiency in 3D CAD modeling (SolidWorks preferred), engineering drawing creation (GD&T), and tolerance stack analysis.
Hands-on experience with mechanical prototyping, assembly, and testing. Familiarity with FEA, CFD, and thermal analysis tools.
Excellent problem-solving, creative thinking, communication, and collaboration skills for effective cross-functional teamwork
Self-starter with a proven ability to deliver functional designs in a rapid development environment and a track record of innovation and continuous improvement. Ability to work independently, manage multiple projects in a fast-paced environment.
Experience with volume manufacturing of electric motors or generators is a plus, including: Design for Quality, inspection and testing methods, insulation system design and certification, formed and wound coil design, magnetic material specification and handling, lamination design and manufacturing
Passion for clean energy and commitment to creating a more sustainable world