Mechanical Engineer

Salary Range $135K/yr - $175K/yr About Avalanche Energy Avalanche Energy is a Washington-based startup building compact, deployable fusion systems through rapid hardware iteration. Rather than pursuing fusion as a single grid-scale outcome, Avalanche develops transportable fusion machines designed to be built, tested, and operated on short cycles, turning real hardware into steady progress. This approach enables near-term applications that demand extreme energy density and endurance—starting with fusion neutron production for radioisotope power and other defense and space uses—while advancing the underlying fusion platform. Backed by U.S. government programs and a team experienced in delivering complex systems, Avalanche is focused on building fusion that runs in the real world, not just on paper. Avalanche might be a fit for you if: You are energized by hands‑on problem solving and building real hardware. You enjoy working in a lab or machine shop, fitting parts together, chasing leaks, and making stubborn systems behave. You are comfortable moving between CAD modeling, design analysis, and elbows‑deep assembly and troubleshooting. You are motivated by delivering solutions to complex problems in aggressive timelines. You care about clean designs, well‑toleranced parts, and systems that work reliably under real‑world conditions. You take pride in hardware that performs because the fundamentals were done right. About the Role Avalanche Energy is seeking a Mechanical Engineer to design, build, and maintain the mechanical systems that support our compact fusion devices. You will work directly on vacuum hardware, structural assemblies, thermal management systems, and supporting laboratory infrastructure, contributing to experiments that are designed, built, and iterated rapidly. This is a deeply hands‑on role. You will be responsible for everything from CAD modeling and component selection to fabrication, assembly, testing, and troubleshooting under demanding conditions. The work spans precision vacuum systems, structural design, thermal and high‑voltage management, and integration with experimental hardware. You will be working with materials ranging from stainless steels to refractory metals and ceramics. This is not a desk job or a simulation‑first role—this is lab‑centered engineering focused on getting complex mechanical systems to work, reliably and repeatably. Responsibilities Design, build, and maintain mechanical and vacuum systems supporting fusion experiments, diagnostics, and laboratory infrastructure. Work alongside physicists and engineers to conceive, implement, and refine mechanical systems for experimental hardware, from initial concept through fabrication, assembly, and iteration. Specify, procure, fabricate, and test mechanical hardware including vacuum vessels, structural mounts, thermal interfaces, feedthroughs, and precision mechanical assemblies. Perform hands‑on troubleshooting of mechanical and vacuum systems, diagnosing issues related to leaks, thermal performance, structural loading, alignment, and hardware fit‑up. Support experiment operation by setting up, validating, and maintaining mechanical systems, vacuum hardware, and associated diagnostics. Provide mechanical insight into experimental results, helping interpret hardware performance, system behavior, and failure modes. Contribute to continuous improvement of lab mechanical practices, documentation, fabrication standards, and build processes. Required Qualifications B.S. degree or higher in mechanical engineering, aerospace engineering, or a closely related field. 5‑8 years of post‑degree experience in hands‑on mechanical engineering roles, preferably in a laboratory or experimental hardware environment. Strong command of mechanical engineering fundamentals, including structural analysis, thermal systems, fluid mechanics, and materials selection. Proficiency in 3D CAD tools (e.g., SolidWorks, CATIA, or equivalent) for design, assembly modeling, and drawing generation. Experience designing, assembling, and operating vacuum systems, including familiarity with pumping systems, gauging, and leak checking. Experience with thermal management design, including heat transfer analysis, cooling system design, and thermal interface materials. Experience working with machine shops and fabrication processes, including tolerance specification, GD&T, and hands‑on assembly of precision mechanical hardware. Familiarity with FEA tools for structural or thermal analysis (e.g., ANSYS, Abaqus, or equivalent). Comfort working directly with physical hardware in a laboratory or machine shop environment, including hands‑on assembly, installation, and test. Desired Qualifications Experience designing or building hardware for laboratory experiments, research programs, or scientific instruments. Experience working with design or fabrication using ceramic materials, including MACOR or Alumina. Experience with high‑vacuum or ultra‑high‑vacuum (HV/UHV) systems, including system design, bakeout, and troubleshooting. Familiarity with plasma physics hardware or fusion‑related systems, such as magnetic coils, ion sources, beam optics, or high‑voltage electrical feedthroughs. Experience with precision machining or direct hands‑on fabrication, including lathe, mill, or other shop equipment. Experience working with cryogenic systems, high‑pressure hardware, or other mechanically demanding environments. Additional Considerations Location: Prefer onsite to support hands‑on laboratory work and close integration with experimental teams. Sites: Tukwila, Washington. Travel: Occasional travel for equipment procurement, integration, or collaboration as needed. Schedule: Standard business hours, with flexibility during experimental campaigns or critical test periods. Excellent medical, dental, and vision benefits. 10 paid holidays and a company‑wide December holiday break. Generous paid vacation and sick time. Small, tight‑knit team with low barriers to action. Exposure to a wide range of challenging, hands‑on engineering problems. Meaningful equity in the form of stock options. Stock Options We are embarking on an unrealistically ambitious project that will change the course of life on earth. We are all owners; success will be shared. Paid Time Off A successful company requires rested, enthusiastic and energetic employees. We offer excellent paid time off for you to take care of yourself so we all succeed. Flexible Schedule Our job is to build and test fusion devices, not warm seats. We will work with you on a schedule that fits all of us. Competitive Salary We are a start‑up with constraints, but we take care of our people. Health Insurance We need a healthy team. We provide 100% employer paid health, dental and vision insurance premiums, with one of the best plans available. Team Offsites A couple times a year we head somewhere new and do something fun to change our paradigm. #J-18808-Ljbffr