Mechanical Design Engineer (Combustion)

We are seeking a Mechanical Design Engineer for our Combustion team to own the 3D design of high-temperature, high-pressure hardware from concept through fabrication.  You’ll collaborate closely with combustion engineers, analysts, and test engineers to develop practical, test-ready systems. Your work will leverage metal additive manufacturing, precision machining, and algorithmic design techniques to push the boundaries of modern fabrication. 

Arbor’s team of world-class engineers and scientists are developing a scalable, low-cost approach to Bioenergy with Carbon Capture and Storage (BECCS) based on modern rocket engine technology. BECCS is a carbon dioxide removal (CDR) approach that uses biomass to produce energy and remove CO₂ from the atmosphere and store it permanently underground, while ensuring food security, rural livelihoods, and biodiversity are not affected. Our modular technology leverages the power density of supercritical CO2 to enable compact gasification, oxy-combustion, and high-pressure turbo-expansion to convert abundant waste biomass into clean electricity, water, and high-purity CO2, capturing and sequestering all emissions from the process. Our team brings together a passion for science, technology, and global stewardship to make low-cost, high-quality carbon removal and baseload power a reality. 

• Lead detailed 3D modeling of complex components and assemblies. 
• Apply Design for Additive Manufacturing (DfAM) principles to optimize performance, cost, and manufacturability. 
• Create complete drawing packages with GD&T, assembly documentation, and bill of materials (BOMs). 
• Translate engineering requirements into practical, buildable designs. 
• Generate work instructions and collaborate with technicians during builds and test campaigns. 
• Continuously iterate based on feedback from analysis, testing, and fabrication. 

• Bachelor’s degree in Mechanical, Aerospace, or a related Engineering discipline. 
• 3+ years of experience in mechanical design of high-performance systems. 
• Proficiency in CAD software (Siemens NX preferred; others such as SolidWorks or Creo also acceptable). 
• Experience producing fully detailed drawing packages including GD&T and manufacturing specs. 
• Experience with additive manufacturing and DfAM principles. 
• Understanding of additive constraints: overhang angles, support strategy, build orientation, powder removal, etc. 

• Exposure to material behavior and surface finish considerations in high-temperature AM alloys (e.g., Inconel 625/718, Hastelloy, Haynes). 
• Familiarity with FEA or fluid/thermal analysis workflows. 
• Prior experience in a fast-paced, hands-on R&D or startup environment. 
• Exposure to combustion systems, high-temperature materials, or pressure vessels. 

• Stock options 
• Medical, dental, and vision insurance (Arbor covers 90% for employees) 
• Basic life insurance fully covered 
• Health savings account (HSA) with matching 
• Flexible savings account (FSA) 
• Unlimited PTO   
• 12+ company holidays, including Earth Day!   
• 401(k) 
• Commuter benefits 
• Annual learning and development stipend 
• And more! 

Arbor is an equal-opportunity employer.  We never discriminate on the basis of race, religion, national origin, gender identity or expression, sexual orientation, age, or marital, veteran, or disability status. Building a global solution to this global problem will require humans of all varieties to contribute diverse ideas and experiences, so we have put finding and hiring qualified individuals from underrepresented groups at the top of our priority list.