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F4

Summer 2025 · Active

Automating compliance checks for engineering drawings

Location: San Francisco, US

Founded: 2025

Team size: 5

About

Built by former Tesla & SpaceX engineers, F4 is a platform that helps you catch and fix drawing compliance issues instantly. F4 ensures design engineers never release noncompliant drawings—and suppliers never misinterpret them. We help hardware teams eliminate costly scrap, rework, and miscommunication at the root. With a compliant drawing, F4 generates end-to-end drawing interpretations for standard definitions, inspection plan, and tolerance analysis application. F4 automatically interprets all GD&T symbols, datums, and notes based on the correct standards - no more second-guessing or misreading intent. Everyone from design to manufacturing sees the same definition, keeping teams aligned and avoiding costly miscommunication. F4 generates a complete inspection plan straight from the drawing, so quality teams know exactly what to measure, how, and where. This eliminates manual setup, reduces delays during first article inspection, and helps catch issues before they reach production. F4 gives engineers everything they need from the drawing to set up a reliable tolerance analysis, applicable features, and rule exceptions. By making it easy to bridge engineering drawings to tolerance analysis, teams can catch potential fit or function issues early - before parts are fabricated and assembled.

Founders

  • Paul ShinFounder

    CEO & Co-Founder @ F4 | Previously Mechanical Design Engineer @ Tesla Drive Unit where I owned 6 CyberCab & SEMI production parts and led the global drive unit heat exchanger program producing 3M+ units annually | Earlier, pioneered liquid-bipropellant rocketry @ UA & UC Berkeley

  • Aidan CantuCTO & Co-Founder

    CTO & Co-Founder @ F4 | Previously Avionics Test Engineer @ SpaceX where I designed and built hardware for Raptor 3 engine testing | Earned B.S. & M.S. in Electrical Engineering in four years with minors in CS & Math