Mechanical Design Engineer

Pacific Fusion; Fremont (CA); On-site; USD 138,000 - 207,000; Full time

Benefits offered by this job

Equity plan

6% employer 401k matching

Generous paid time off

Medical, Dental, and Vision insurance

Job summary

Pacific Fusion is seeking a Senior Vacuum Seal Engineer to advance the design and integration of complex sealing systems for vacuum environments. You will lead experiments, validate test plans, and guide cross-functional teams across internal groups, vendors, and partners.

The role emphasizes FMEA, tolerance analysis, and reliable seal integration, with mentoring responsibilities and close collaboration with the external suppliers. Base compensation reflects high-demand expertise.

Qualifications

• Bachelor's or Master's in Mechanical/Aerospace or related field.
• 5+ years in mechanical design focused on vacuum seals in various vacuum environments.
• Strong CAD, FEM, and engineering analysis tool proficiency.
• Expertise in tolerance analysis, FMEA, seal design, and mechanical integration.

Responsibilities

• Design and analyze large, high-performance vacuum seals for various transitions.
• Lead experimental design and testing with internal teams, vendors, and academic partners.
• Conduct research into novel sealing techniques; define and execute test campaigns.
• Perform FMEA and tolerance stack-up analyses to ensure seal reliability and safety.
• Design test assemblies and risk-reduction.
• Review and present technical work across multidisciplinary teams; support system-level discussions.
• Provide subject-matter expertise in sealing strategies and guide system integration.
• Document sealing processes, validation data, and lessons learned.
• Mentor and support junior engineers on design challenges.
• Interact with suppliers of vacuum systems components for purchasing.

Skills

Vacuum seals design

CAD

FEM

Engineering analysis tools

Tolerance analysis

FMEA

Mechanical integration

Education

Mechanical/Aerospace degree

Tools

CAD software

FEM software

Engineering analysis tools

Job description

About Pacific Fusion

Pacific Fusion was founded in 2023 with the mission to power the world with abundant, affordable, clean energy.

We are rapidly designing and building a pulser-driven inertial fusion system to achieve net facility gain (more fusion energy output than stored energy input). In parallel, we are developing the key components required to build affordable fusion systems.

Our plans are ambitious. We have raised over $900M so far from incredible investors, resourcing us to deliver on these plans. We are bringing together the best scientists, engineers, and operators from the fusion community, hard tech industry, and other sectors. We are united by a shared sense of urgency to provide clean power for the world, particularly managing climate change while meeting growing global energy demand. You can read more about us in this letter from our founders.

About Pacific Fusion

Pacific Fusion was founded in 2023 with the mission to power the world with abundant, affordable, clean energy.

We are rapidly designing and building a pulser-driven inertial fusion system to achieve net facility gain (more fusion energy output than stored energy input). In parallel, we are developing the key components required to build affordable fusion systems.

Our plans are ambitious. We have raised over $900M so far from incredible investors, resourcing us to deliver on these plans. We are bringing together the best scientists, engineers, and operators from the fusion community, hard tech industry, and other sectors. We are united by a shared sense of urgency to provide clean power for the world, particularly managing climate change while meeting growing global energy demand. You can read more about us in this letter from our founders.

Why This Role Matters

This role is critical to the design of systems and components, prototyping, and implementing new solutions to pulser systems

What You'll Do

• Design and analyze large, high-performance vacuum seals for water-to-air, air-to-high-vacuum, and water-to-high-vacuum transitions
• Lead experimental design and testing in collaboration with internal teams, external vendors, and academic partners
• Conduct research into novel sealing techniques; define, execute, and evaluate test campaigns
• Perform FMEA and tolerance stack-up analyses to ensure seal reliability and system safety
• Design test assemblies and risk-reduction
• Review and present technical work across multidisciplinary teams; contribute to system-level integration discussions
• Provide subject-matter expertise in sealing strategies and help guide the integration of systems in the target area
• Document sealing processes, validation data, and lessons learned
• Mentor and support junior engineers on design and integration challenges
• Interact with suppliers of vacuum systems components and electrical testing components for purchasing

What You Bring

• Bachelor's or Master's degree in Mechanical, Aerospace, or a related engineering field, or equivalent experience
• 5+ years of mechanical design experience with a focus on vacuum seals and systems, including rough, high, and ultra-high vacuum environments
• Strong proficiency in CAD, FEM, and engineering analysis tools
• Proven expertise in tolerance analysis, FMEA, seal design, and mechanical integration

Bonus Points For

• Experience in high vacuum systems design and assembly
• Experience using CREO
• Experience of high voltage electrical work
• Experience implementing instruments controls and software

Pay Range

$138,100—$207,100 USD

Total Compensation And Benefits For Eligible Employees

• Industry-competitive salary
• Equity plan
• 6% employer 401k matching
• Generous paid time off (including sick leave, vacation, paid family leave)
• Medical, Dental, and Vision insurance

Actual base salary offered will be determined by: experience, skills, and work location. This range is for base salary, our total compensation includes equity and benefits.

EQUAL OPPORTUNTITY

Pacific Fusion is committed to creating a diverse environment and is proud to be an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status.

Pacific Fusion is committed to providing reasonable accommodations for qualified individuals with disabilities in our job application procedures and throughout employment. If you need assistance or any accommodation, please let us know.

U.S. EXPORT CONTROL COMPLIANCE

This position may require access to information or technology that is subject to U.S. export control laws, such as ITAR or EAR. Under these regulations, we are required to ensure that such access is provided only to individuals who are classified as 'U.S. Persons.' This status includes U.S. citizens, U.S. nationals, lawful permanent residents (green card holders), and asylees and refugees with such status granted, not pending.