rattleCAD Tutorial: How to Move from Bike Fit Data to CAD Drawings

rattleCAD is a specialized, parametric 2D computer-aided design (CAD) software built exclusively for bicycle design and bespoke framebuilding. Developed since 2008 by Austrian cyclist and programmer Manfred Rosenberger, it guides builders from initial rider measurements to finalized workshop blueprints. The Core Design Principle

The software is built around a distinct “Outside-In” method. Instead of starting with arbitrary tube lengths, the kernel uses the rider’s contact points—the exact saddle and handlebar positions relative to the bottom bracket—as its primary reference points. The frame geometry skeleton adapts dynamically to fit these fixed parameters. Key Features rattleCAD 4.0 – Bicycle FrameBuilding CAD – Home