Mechanical Design Engineer II

About Us

At Antares, our long-term mission is to make clean energy abundant from Earth to the Asteroid Belt. We’re fueled by the belief that advanced nuclear energy can strengthen our military, solve the climate crisis, elevate global living standards, and expand humanity's presence in outer space. To achieve our mission, we’re building mass-producible, inherently safe, deployable microreactors that can be used terrestrially, underwater, and in space.

The Antares team hails from SpaceX, the White House, the Pentagon, the Department of Energy, MIT, Rigetti Computing, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Idaho, Oak Ridge, Los Alamos, and Savannah River. Antares has raised over $600M in venture capital from top-tier investors and has hundreds of million-dollars on contract with the military services, NASA, and the Department of Energy.

About the Role

As a Mechanical Design Engineer in our Electronic Hardware, you'll serve as the Responsible Engineer (RE) for the mechanical design and development of hardware supporting the reactor's electronic systems. This includes the design of enclosures, equipment racks, mounting hardware, cable management features, and structural supports for control system electronics and associated instrumentation. You'll work closely with electrical, controls, manufacturing, and test engineers to define system layouts, enclosure requirements, thermal and environmental considerations, and verification plans. The ideal candidate has experience designing and releasing electronic hardware assemblies for production, creating detailed mechanical drawings and documentation, and managing CAD models, bills of materials (BOMs), and engineering data within a Product Data Management (PDM) system.

Roles and Responsibilities:

• Design and develop mechanical hardware for reactor electronic systems, including enclosures, equipment racks, mounting hardware, cable management, and structural support assemblies.

• Create and maintain 3D CAD models, manufacturing drawings, bills of materials (BOMs), and engineering documentation to support fabrication and product release.

• Perform engineering calculations and analyses to validate the structural, thermal, and environmental performance of mechanical hardware.

• Collaborate with electrical, controls, manufacturing, and test engineers to define mechanical interfaces, packaging layouts, and installation requirements.

• Support prototype fabrication, testing, design verification, supplier engagement, hardware deployment, and the resolution of manufacturing, assembly, and field issues.

• Maintain engineering configuration within the Product Data Management (PDM) system and participate in design reviews throughout the product development lifecycle.

Basic Qualifications:

• Bachelor's degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or a related engineering discipline.

• 2+ years of professional experience designing and developing mechanical hardware for electronic systems, including enclosures, mounting hardware, racks, or structural support assemblies.

• Experience creating 3D CAD models, detailed engineering drawings, and bills of materials (BOMs) for production hardware.

• Demonstrated ability to perform engineering calculations to size and validate mechanical components and support structures.

• Familiarity with geometric dimensioning and tolerancing (GD&T) and standard manufacturing processes for fabricated and machined components.

• Experience managing engineering documentation, revisions, and product structures within a Product Data Management (PDM) or Product Lifecycle Management (PLM) system.

• Demonstrated ability to collaborate effectively with multidisciplinary engineering teams, including electrical, controls, manufacturing, and test engineers, while clearly communicating technical information to both technical and non-technical stakeholders.

Preferred Skills & Experience:

• Master's degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, or a related engineering discipline.

• Experience designing electronic enclosures, equipment racks, mounting hardware, and structural support assemblies for demanding operating environments.

• Knowledge of electronic packaging principles, including thermal management, vibration isolation, EMI/EMC considerations, nuclear radiation shielding, cable management, and environmental sealing.

• Experience performing structural and thermal analysis using engineering tools such as ANSYS, Femap, COMSOL Multiphysics, or equivalent FEA software.

• Experience designing for manufacturing and assembly (DFMA), including sheet metal, machined, welded, and fabricated components.

• Experience managing CAD models, engineering drawings, and product structures within a Product Data Management (PDM) or Product Lifecycle Management (PLM) system.

• Experience in the nuclear, aerospace, defense, robotics, or other highly regulated or high-reliability industries.

Additional Requirements:

• Ability to work long hours and weekends as necessary to support critical milestones.

Location :

• We are located in Torrance, CA in a 322,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access

Culture

At Antares, we like to specifically tie each role to our founding document’s set of values–here are the top five cultural values we think you should believe at your core to be successful:

• Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities, conflicting policies, perverse incentives, and emergent and path-dependent properties. First principles thinking alone is insufficient. Think probabilistically and then take action. “If you want to be certain, then you are apt to be obsolete.” Over-optimizing the components often degrades the system

• Obsess over the End User - The customer and end user are often not the same. We will never build globally competitive commercial products if we lose sight of our end users and their entire interaction with the product life cycle

• Be Unconstrained by Convention - Our only limits are the laws of physics. Many, even experts, will say what we are working on is impossible. They said the same about SpaceX reusing rockets. Generationally impactful companies, by definition, must accomplish the seemingly impossible. If it were easy, it would have already been done. Never shy away from a solution because it has never been tried before, and never choose to do something because that's “how it's always been done”

• Go Where the Work I s - Never miss a chance to meet a customer, user, or stakeholder face to face, even if that means hopping on a plane. If you can’t make it, find a teammate who can channel your intentions and go in your place. Deep work can be done from anywhere, but we believe teams are built in person, and aim to maximize our time together

• Operate in the Grey - Embrace nuance in pursuit of truth. Question every fundamental assumption

Equal Opportunity

Antares is an Equal Opportunity Employer. Employment decisions are based solely on merit, competence, and qualifications, without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status.

ITAR Requirements

To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here .