# Custom Bicycle & E-Bike 1/2" Pitch Chainring .DXF/.STL

Create custom tooth-count 36T–58T single-speed, track, and mid-drive e-bike chainrings in AutoCAD .DXF and 3D-printable prototype .STL.

## Engineering Geometry & Export Specification
- Computes 12.70mm bicycle pitch seating geometry for CNC 7075-T6 chainrings and laser-cut steel cargo-bike drives.
- CAD Outputs: 0.005mm AutoCAD R12 `.DXF`, `.SVG`, Watertight 3D Binary `.STL` (4–40mm face + hub boss + bore), and `1:1` Printable `.PDF`.
- Pricing: Free Spec Proof PDF ($0) · Single CAD Pack ($11.90) · Mechanical Engineer Pro ($19.00/mo).
- Live Interactive Workbench: https://gearcadpro.com/templates/bicycle-ebike-chainring-130bcd-dxf.html