Gerber Solder Paste Layer to Solder Stencil Converter

A Go tool to convert Gerber files (specifically solder paste layers) into 3D printable STL stencils.

Features

• Parses standard RS-274X Gerber files.
• Supports standard apertures (Circle, Rectangle, Obround).
• Supports Aperture Macros (AM) with rotation (e.g., rounded rectangles).
• Automatically crops the output to the PCB bounds.
• Generates a 3D STL mesh optimized for 3D printing.

Usage

Run the tool using go run:

go run main.go gerber.go [options] <path_to_gerber_file> [optional_board_outline_file]

Options

• --height: Stencil height in mm (default: 0.16mm).
• --wall-height: Wall height mm (default: 2.0mm).
• --wall-thickness: Wall thickness in mm (default: 1mm).
• --keep-png: Save the intermediate PNG image used for mesh generation (useful for debugging).
• -server: Start the web interface server.
• -port: Port to run the server on (default: 8080).

Example

go run main.go gerber.go -height=0.16 -keep-png my_board_paste_top.gbr my_board_outline.gbr

This will generate my_board_paste_top.stl in the same directory.

Web Interface

To start the web interface:

go run main.go gerber.go -server

Then open http://localhost:8080 in your browser. You can upload files and configure settings via the UI.

3D Printing Recommendations

For optimal results with small SMD packages (like TSSOP, 0402, etc.), use the following 3D print settings:

• Nozzle Size: 0.2mm (Highly recommended for sharp corners and fine apertures).
• Layer Height: 0.16mm total height.
  • First Layer: 0.10mm
  • Second Layer: 0.06mm
• Build Surface: Smooth PEI sheet (Ensures the bottom of the stencil is perfectly flat for good PCB adhesion).

These settings assume you run the tool with -height=0.16 (the default).

How it Works

1. Parsing: The tool reads the Gerber file and interprets the drawing commands (flashes and draws).
2. Rendering: It renders the PCB layer into a high-resolution internal image.
3. Meshing: It converts the image into a 3D mesh using a run-length encoding approach to optimize the triangle count.
4. Export: The mesh is saved as a binary STL file.

License

This project is licensed under the MIT License - see the LICENSE file for details.