7.3. Mechanical Engineer II
Other Engineering
Burlington, MA, USA
USD 90k-120k / year + Equity
Posted on Jun 24, 2026
About Phoenix Tailings
Phoenix Tailings is a rapidly-growing clean mining and metals production startup dedicated to sustainable and economic critical metals production. Our mission is to be the world's first fully clean mining and metals production company, producing the resources needed for the next generation of our economy.
Why Phoenix Tailings
At Phoenix Tailings, we believe that nothing great is ever accomplished alone or without the passion of people who push and motivate one another. If you are someone who shares our relentless pursuit of a better future, passion for innovation, and are excited about working with some of the top innovators in the world, then this is the place for you.
Our Values:
● You are only crazy if you are wrong, it’s ok to be wrong
● Lead with Compassion
● Be Resourceful
● Listen
● Hustle
Who We Are Looking For:
Phoenix Tailings is looking for a Mechanical Engineer II to help take next-generation processing equipment from concept to deployment. In this role, you will design, build, test, validate, and commission complex mechanical systems that support high-temperature electrolysis, furnace technologies, and innovative electrochemical and thermal processes.
This is a hands-on engineering role for someone who thrives in a fast-paced R&D environment and is excited by the challenge of turning ambitious concepts into reliable, deployed hardware. You will work on first-of-a-kind equipment that combines mechanical, thermal, vacuum, and process engineering to solve complex challenges at the forefront of industrial decarbonization, advanced manufacturing, and critical metals production.
Key Responsibilities:
- Own mechanical systems and equipment from early concept development through design, fabrication, testing, commissioning, and deployment.
- Design and develop novel processing equipment for high-temperature electrolysis, furnace systems, and critical metals production technologies.
- Create 3D CAD models, assemblies, drawings, and technical documentation using SolidWorks to support fabrication, procurement, assembly, installation, and commissioning.
- Select and specify critical mechanical components and mechanisms, including pumps, bearings, lead screws, actuators, seals, thermal components, fixtures, and industrial hardware based on engineering analysis and test data.
- Develop and execute verification and validation plans for components, subsystems, and integrated equipment to prove performance, reliability, and readiness for deployment.
- Use Design of Experiments, structured testing, and data analysis to validate new concepts, troubleshoot equipment performance, and make sound engineering decisions.
- Build, assemble, modify, and commission mechanical tooling, fixtures, prototypes, and pilot-scale equipment in hands-on lab, R&D, and production environments.
- Apply V-Model system development principles to connect requirements, system architecture, detailed design, integration, testing, validation, and deployment.
- Investigate mechanical, thermal, vacuum, and process-related issues, identify root causes, and implement practical design improvements that move technology forward.
- Drive rapid design-build-test iterations with urgency while maintaining sound engineering judgment, safety, and documentation discipline.
Qualifications:
- Bachelor’s degree in Mechanical Engineering or a related engineering discipline.
- 3+ years of mechanical engineering experience designing, building, testing, and commissioning complex equipment, industrial systems, process hardware, or R&D systems.
- Familiarity with V-Model (V-Diagram) based system development methodologies
- Strong SolidWorks experience, including part design, assemblies, detailed drawings, and design documentation for fabrication and assembly.
- Experience developing and executing test plans for system, subsystem, or component verification and validation.
- Experience selecting and integrating mechanical components such as pumps, actuators, bearings, lead screws, seals, fasteners, thermal systems, and industrial hardware.
- Hands-on experience with mechanical tooling, fixtures, prototype assembly, equipment troubleshooting, and commissioning in a lab, pilot, manufacturing, or industrial environment.
- Able to wear a respirator
- Ability to lift up to 50lbs
We offer a competitive compensation package that is based on expertise. We also offer the following benefits:
- Healthcare: 100% Medical, dental, and vision coverage for employee.
- Stock Options: Ownership in a fast-growing venture-backed company.
- Time Off: Unlimited PTO.
- Learning: Learning and development opportunities to grow your skills and career.
This pay range reflects best estimate for the total cash compensation which includes salary + discretionary bonus for this role. Total package may vary based on experience and qualifications.
Pay Range: $90,000- $120,000 total cash compensation plus equity
