Staff Manufacturing Process Engineer
Menlo Park, CA, USA
USD 137,500-162k / year + Equity
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
Job Overview
We are seeking a highly capable Senior/Staff Manufacturing Process Engineer with a strong foundation in manufacturing process planning, industrial engineering, and data-driven problem-solving to bridge the gap between product development and scalable manufacturing.
In this role, you will partner closely with Mechanical, Electrical, Manufacturing, Quality, and Supply Chain teams to develop robust, scalable manufacturing processes that enable safe, repeatable, and high-volume production. You will drive end-to-end process planning, PFMEA workshops, risk mitigation strategies, process validation, and quality planning to ensure new products launch successfully and existing products continuously improve.
This is not a downstream execution role. You will proactively influence product and process decisions by leveraging shop floor data, structured experimentation, and lessons learned from production to eliminate manufacturing risks before they impact volume production.
The ideal candidate combines strong process engineering fundamentals, lean manufacturing principles, and hands-on manufacturing experience, and thrives in a fast-paced, highly collaborative environment where continuous improvement is part of the daily culture.
What You'll Do
Develop, validate, and optimize manufacturing processes from early prototype builds through high-volume production
Lead manufacturing process validation activities using PFMEA, DOE, capability studies (Cpk), and GR&R
Drive cross-functional, closed-loop risk mitigation plans by partnering with Design Engineering, Quality, and Operations
Establish manufacturing readiness plans, process validation strategies, and quality gates for new product introductions
Partner with Industrial Engineering to evaluate cycle times, line balancing, and resource utilization using Yamazumi charts and time studies
Drive touch-time reduction initiatives through process optimization, improved assembly sequencing, ergonomic improvements, fastening strategies, automation opportunities and subsystem testing
Lead structured root cause investigations using 8D, 5 Whys, DOE, and statistical analysis to improve first-pass yield and process capability
Identify and eliminate manufacturing bottlenecks to improve throughput, labor productivity, and overall equipment effectiveness (OEE)
Champion Lean Manufacturing, error-proofing (Poka-Yoke), standardization, and continuous improvement initiatives across production
Own the transition of assembly processes from prototype builds to scalable production systems
Partner with Quality, Supply Chain, Operations, and NPI teams to successfully launch new manufacturing processes
Support factory layout development, production line design, capacity planning, and equipment selection
Support new factory launches, manufacturing transfers, and production ramp activities across domestic and international sites
Manufacturing Process Development
Manufacturing Optimization & Operational Excellence
Manufacturing Scale-Up
What You'll Bring
7–10+ years (Senior) or 10–15+ years (Staff) of manufacturing/process engineering experience supporting complex electromechanical products
Expertise in PFMEA, Control Plans, Process Flow Diagrams, DOE, SPC, 8D, Cpk, and GR&R
Experience developing scalable manufacturing processes and supporting New Product Introduction (NPI) from prototype through high-volume production
Experience developing assembly equipment, fixtures, gauges, and automation systems
Strong knowledge of Lean Manufacturing, Six Sigma, Kaizen, line balancing, Yamazumi charts, time studies, and capacity modeling
Proven ability to lead cross-functional technical initiatives and influence engineering decisions through data
Experience working in fast-paced NPI environments with evolving designs and manufacturing challenges
Experience in automotive, aerospace, energy, or other high-volume electromechanical manufacturing environments
What Sets You Apart
Hands-on mindset—you enjoy working on the production floor to validate ideas, troubleshoot issues, and implement improvements
Comfortable making technical decisions in ambiguous situations while balancing quality, cost, schedule, and manufacturability
Passion for Lean Manufacturing with a bias toward simple, robust, and cost-effective solutions over unnecessary complexity
Strong systems thinking with the ability to connect product design, manufacturing processes, quality, and operational performance
Does your experience not meet all of our posted requirements? Studies have shown that some people are less likely to apply to positions unless they meet every listed requirement. At Mainspring, we are committed to building a diverse, inclusive, flexible, and collaborative environment, so if you want to help us transition the world to clean and affordable electricity, and don’t meet all posted requirements for a particular role, we’d still love to hear from you. Mainspring can sometimes be flexible enough to shift responsibilities for the right person, or otherwise identify open or upcoming roles that may better fit your professional background.
In more traditional words, Mainspring Energy, Inc is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.
This compensation and benefits information is based on Mainspring Energy's estimate as of the date of publication and may be modified in the future. We generally do not negotiate on salary once we have made an offer. The level of pay within the range will depend on a variety of job-related factors that may include location, relevant prior experience and/or education, or particular skills and expertise. New hires joining the company tend to be paid within the starting base pay range noted above, with opportunities to increase pay over time based on development of additional skills, competencies, and company-specific knowledge.
137500 - 162000 USD a year
This position is onsite at our Menlo Park HQ. The salary will be adjusted to reflect local market conditions based on employee location as well as the experience of the employee. Along with the base salary, Mainspring offers pre-IPO stock options + benefits.