Mechanical Technician

ABOUT SUBCRITICAL SYSTEMS

Subcritical Systems, Inc. is a venture-backed startup in Austin, Texas building the accelerator driven systems and the only US commercial manufacturer of accelerator cavities. What Space X did for rockets, we plan to do for accelerator cavities and commercialize across applications of power production, medical isotopes, semiconductors and waste transmutation.

We are in the process of building the Energy Amplifier, a novel nuclear fission system in which a particle accelerator drives a subcritical core, making meltdown physically impossible for clean power production. Due to its inherent safety, our system has a more streamlined licensing process. Our founding team includes successful entrepreneurs with a track record of building several multibillion dollar companies in deep-tech, and scientists who were leading U.S. national labs with deep experience in accelerator & nuclear technologies.

We are actively hiring to expand our team as we work toward licensing, regulatory submissions, and construction of our first energy amplifier. More information is available at subcritical.com.

ROLE SUMMARY

We are looking for a skilled Mechanical Technician to join our engineering and scientific team. You will fabricate, assemble, and test mechanical systems and subassemblies supporting advanced particle accelerator and nuclear technology development. The majority of your time will be hands-on in the lab and shop building hardware to specification, supporting test campaigns, and iterating quickly on prototype designs.

This is a primarily hands-on role requiring careful mechanical assembly, fixture and tooling fabrication, and the ability to read and mark up engineering drawings as designs evolve. Occasional off-shift or weekend work may be required to support test schedules; paid overtime applies.

KEY RESPONSIBILITIES

Fabrication & assembly

• Fabricate, assemble, and disassemble mechanical components, subassemblies, and test fixtures to engineering drawings and specifications
• Operating shop equipment (mills, lathes, drill presses, hand tools) and precision measurement instruments (calipers, micrometers, and dial indicators).

Systems installation & commissioning

• Support installation, verification, and commissioning of vacuum, compressed gas, fluid, and cryogenic systems in partnership with engineering and scientific staff.

Test campaign support

• Set up instrumentation, run test procedures, log data, and assist with troubleshooting during test campaigns alongside engineers and scientists.

Documentation

• Document work through redline drawings and test reports; communicate findings and results clearly with the engineering team as designs evolve.

Safety & shop standards

• Maintain a clean, organized, and safe work area in accordance with lab and company safety practices at all times.

QUALIFICATIONS

Required

• 2+ years of hands-on mechanical fabrication, assembly, or maintenance in automotive, aerospace, semiconductor, laboratory, or similar hardware environments
• Proficiency with standard shop equipment and precision measurement tools; ability to read and interpret mechanical drawings and GD&T
• Strong attention to detail and disciplined documentation habits; familiarity with CAD viewers for reviewing and marking up drawings
• Good verbal communication skills; ability to coordinate effectively with engineers, scientists, and fellow technicians
• Ability to coordinate effectively with engineers, scientists, and fellow technicians.

Preferred

• Associate's degree or technical certificate in mechanical technology, manufacturing, or mechatronics preferred; relevant hands-on experience may substitute
• Experience with ultra-high vacuum practices, cryogenic hardware, or clean assembly protocols, welding, brazing, or soldering experience.
• Welding, brazing, or soldering experience

BENEFITS

Benefits: We offer health, dental, and vision insurance.

LOCATION & WORK POLICY

This role is fully in person in Austin, Texas. Our facility is located next to Austin Airport.

HOW TO APPLY

Apply on LinkedIn or submit your resume and a brief cover letter to careers@subcritical.com with the subject line "Mechanical Technician - Application". Applications are reviewed on a rolling basis.