Computer Aided Design Intern Jobs in Fullerton, CA

About Castelion

Castelion is bringing a new approach to defense development and production: one that focuses on short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production at scale. We're designing, building, and testing next generation long range strike weapons systems to give America and its Allies a definitive edge and deter future conflicts.

Position Summary

The Mechanical CAD Designer/Drafter supports the planning, coordination, and execution of mechanical engineering projects from concept through production. This role serves as the link between engineering, manufacturing, supply chain, and project management by maintaining product configurations, managing Bills of Materials (BOMs), coordinating engineering changes, and tracking project schedules and deliverables. The position also provides hands-on engineering support through CAD model and drawing updates, documentation control, and configuration management to ensure products are accurately released and maintained throughout their lifecycle.

Essential Responsibilities

• Manage and maintain engineering Bills of Materials (BOMs) for new and existing mechanical products.
• Maintain CAD assemblies, part configurations, and engineering documentation within the company's CAD and Product Lifecycle Management (PLM) systems.
• Perform minor mechanical CAD modeling and drawing revisions under the direction of design engineers, including dimension updates, tolerance changes, and documentation corrections.
• Coordinate the Engineering Change Request (ECR) and Engineering Change Order (ECO) process, ensuring design changes are accurately documented, reviewed, approved, and released.
• Monitor project schedules, engineering deliverables, milestones, and key performance metrics to support on-time project completion.
• Track design release status, prototype builds, testing activities, and production readiness.
• Ensure engineering documentation, drawings, and specifications comply with company drafting standards and revision control requirements.
• Support mechanical engineers with prototype builds, manufacturing documentation, and design verification activities.
• Coordinate with Manufacturing, Quality, Supply Chain, and Production to implement engineering changes and support new product introductions.
• Assist with configuration management throughout the product lifecycle, ensuring product structures and documentation remain accurate and traceable.
• Develop and maintain project dashboards, schedules, and status reports for engineering leadership.
• Identify opportunities to improve engineering workflows, documentation practices, and change management processes.

Required Qualifications

1. Associate's or Bachelor's degree in Mechanical Engineering, Mechanical Engineering Technology, Aerospace Engineering, or a related technical discipline
2. At least two years of experience creating and maintaining detailed mechanical drawings, assemblies, and manufacturing documentation using CAD software.
3. Experience generating production-ready engineering drawings including dimensioning, tolerancing, and GD&T in accordance with company standards.
4. Execute drawing revisions and engineering change orders (ECOs) to support ongoing product development and manufacturing.
5. Experience developing and updating bills of materials (BOMs), assembly instructions, and release packages.
6. Experience collaborating with mechanical engineers to convert conceptual and 3D designs into complete fabrication and manufacturing documentation.
7. Experience with Product Lifecycle Management (PLM), Product Data Management (PDM), or Enterprise Resource Planning (ERP) systems.
8. Strong organizational, analytical, and problem-solving skills.
9. Excellent communication and cross-functional coordination abilities.
10. Proficiency in Microsoft Excel, Project, and other project tracking tools.

Preferred Qualifications

• Experience supporting new product introduction (NPI) programs.
• Familiarity with machining, sheet metal fabrication, welding, plastics, or mechanical assembly processes.
• Experience creating or revising mechanical drawings and technical documentation.
• Knowledge of Design for Manufacturing (DFM) and Design for Assembly (DFA) principles.

Benefits And Perks

All full-time employees are granted meaningful long-term equity, sharing in the company's significant growth trajectory. We offer four (4) weeks of paid time off, ten (10) company-paid holidays, and comprehensive health benefits - including 100% employee-covered medical and strong dependent coverage, along with dental and vision plans. We also provide paid parental leave to support growing families, a $100 monthly fitness stipend to promote health and performance, and onsite EV charging for convenience. In addition, employees enjoy perks like catered meals, company-covered food during high-demand periods, and a fully stocked kitchen to stay fueled throughout the day.

While this position does not currently require a U.S government-issued security clearance, it may in the near future. Therefore, the ability to obtain and maintain a U.S. government–issued security clearance is required. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance.

Affirmative Action/EEO Statement

Employment with Castelion is governed on the basis of competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.