Senior Mechanical Engineer

About the Company: This San Diego-based climate-tech startup is building thermochemical energy storage (TCES) systems for energy-intensive industries. The technology lets industrial operators time their power usage to cheaper periods and replace fossil-fuel combustion with electrified heat — delivering a continuous stream of combustion-free, high-temperature air (up to 1,200°C). The company is venture-backed by major climate and energy investors.

The Opportunity: We're looking for a hands-on, welding-capable Engineering Technician to help fabricate parts and build out testing rigs, instrumentation, sensors, prototypes, and power electronics hardware. This is a great fit for someone early in their career (2-4 years of hands-on experience, ideally out of a strong technical program) who wants to get real reps on cutting-edge R&D hardware in a fast-moving startup. You'll split time between independent fabrication work and close collaboration with the engineering team, directly shaping components for next-generation high-temperature energy storage systems.

What You'll Do: Read and interpret 3D CAD models, 2D drawings, and spec sheets to plan, measure, and cut raw stock for part production Perform TIG/MIG welding on structural builds and run shop equipment (mills, lathes, drill presses, band saws) to fabricate or rework parts Support assembly of mechanical and electromechanical systems Check finished parts for dimensional accuracy and weld quality ahead of inspection Rework and repair parts, prototypes, and test rigs on the fly to keep pace with R&D needs — welding, grinding, cutting, machining as needed Fabricate with high-temperature and specialty materials (refractory metals, ceramics, alloys) built for thermochemical-grade durability Work directly with engineers to troubleshoot fabrication issues and flag design-for-manufacturability improvements Inspect welded/fabricated components for structural soundness, finish, and tolerance Keep welding equipment and machine tools properly maintained, and follow safety protocol around welding, high-heat materials, and machinery Log build data — assembly steps, fabrication parameters, modifications — and loop engineering/R&D in with real-time feedback

Physical Requirements: Mix of desk-based design/documentation work and hands-on shop/lab time Able to lift/carry up to 50 lbs. (team lift or mechanical assist for heavier loads)Strong hand dexterity for assembly, fabrication, and equipment operation Sharp visual acuity for reading drawings and spotting dimensional/surface defects Comfortable working in required PPE (safety glasses, heat-resistant gloves, safety shoes, etc.) in high-heat environments Solid grasp of shop/lab safety practices — hazard recognition around high-temp equipment, energized systems, and fabrication machinery Minimal travel (under 5%) for occasional tool/material runs What Success Looks Like Here You communicate directly and proactively — no one has to chase you for updates You pitch in wherever needed, whether that's helping a teammate troubleshoot or flagging something outside your usual scope You're curious about the full system — chemistry, mechanical engineering, power electronics, software — not just your slice of it You factor cost and timeline into your technical decisions, not just elegance You're comfortable moving forward without a fully built-out playbook, and know when to ask versus when to just decide You own your outcomes, including the misses — and focus on fixing and learning rather than explaining