Senior Tooling Engineer

About Castelion

Castelion is bringing a new approach to defense development and production: short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production at scale. The company is designing, building, and testing next-generation long-range strike weapons systems to give America and its allies a definitive edge and deter future conflicts.

The Opportunity

Castelion is looking for a Senior Tooling Engineer to own the end-to-end development of tooling for their products — from concept through implementation on the production floor. You will architect and implement innovative tooling solutions to achieve aggressive production cost, quality, and delivery targets, leading projects from requirements through validation while mentoring junior engineers and technicians.

What You’ll Do

•      Design and develop complex tooling systems including jigs, fixtures, molds, dies, and assembly tools for aerospace manufacturing processes

• •      Create detailed tool designs in CAD and perform tolerance stack-up analysis and FEA to validate designs for durability and precision


• •      Lead tooling projects from concept through production: requirements gathering, design reviews, prototyping, validation, and on-time delivery within budget


• •      Collaborate with manufacturing and production teams to improve tooling efficiency, reduce cycle times, and enhance product quality


• •      Ensure all tooling designs comply with aerospace industry standards such as AS9100 and NADCAP, and implement DFM principles to minimize defects and ensure repeatability


• •      Partner with supply chain teams to select appropriate materials, coatings, and manufacturing methods for tooling


• •      Coordinate with production teams to troubleshoot tooling issues and drive corrective actions


• •      Support quality assurance teams in developing inspection criteria and validating tooling performance


• •      Mentor and provide technical guidance to junior tooling engineers and technicians

You Should Have

• •      5+ years of experience in tooling design and development


• •      Bachelor’s degree in Mechanical, Electrical, or Manufacturing Engineering or a related field


• •      Experience with CAD-based tool design, tolerance stack-up analysis, and FEA for tooling validation


• •      U.S. citizenship or permanent resident status required (ITAR)

Nice to Have

• •      Proven record supporting NPI, pilot runs, and transition to production with robust, scalable manufacturing systems


• •      Experience troubleshooting complex build issues and driving corrective actions to closure


• •      Background working in regulated or defense environments


• •      Experience interfacing with design, systems, test, and supplier teams on manufacturability and production readiness

Compensation and Benefits

Base Salary: $140,000 - $230,000, depending on experience, plus long-term stock incentives for all employees.

Benefits include comprehensive medical, vision, and dental insurance, and four weeks of paid time off per year.