Export 3MF

Export your Gridfinity layout as 3MF files ready for slicing and 3D printing. All geometry is generated client-side using Manifold CSG for guaranteed watertight meshes.

Overview

The 3MF export system converts your bin designs into industry-standard 3MF packages compatible with all modern slicers. Each export includes proper metadata for Bambu Studio integration and multi-object support.

Export Options

Export Single Bin

Selected bin only

One bin geometry
Positioned at world origin
Filename: gridfinity-bin-[WxDxH].3mf
Fast export (<1 second)

Export All Bins

Complete layout

All bins in scene
Grid positions preserved
Filename: gridfinity-layout-[date].3mf
Multi-object 3MF

Use Export All to print an entire baseplate worth of bins in one slicing session.

3MF File Format

The 3MF (3D Manufacturing Format) is a modern replacement for STL:

Format Structure

gridfinity-layout.3mf (ZIP archive)
├── [Content_Types].xml          # MIME type mappings
├── _rels/.rels                  # OPC relationships
├── 3D/
│   └── 3dmodel.model            # Mesh geometry (XML)
└── Metadata/
    ├── model_settings.config    # Bambu Studio metadata
    ├── project_settings.config  # Project config
    └── slice_info.config        # Slice metadata

Why 3MF over STL?

3MF Advantages

Multi-object support
Embedded metadata
Color/material info
Native slicer integration
Smaller file sizes (compressed)

STL Limitations

Single object only
No metadata
No color info
Larger files (uncompressed)
Requires manual positioning

Geometry Generation Pipeline

Step-by-step process:

User clicks Export button
Web Worker generates CSG meshes for each bin
- Manifold WASM ensures watertight geometry
- Boolean operations (unions, subtractions) computed
Manifold mesh extracted:
- Vertices: Float32Array of [x,y,z] coordinates
- Triangles: Uint32Array of [v0,v1,v2] indices
XML serialization:
- <vertices> block with all vertex positions
- <triangles> block with face indices
3MF package assembly (JSZip):
- Content types, relationships, metadata
- OPC (Open Packaging Convention) structure
ZIP compression (DEFLATE)
Browser download triggered

Example 3MF Mesh XML

<object id="1" type="model">
  <mesh>
    <vertices>
      <vertex x="0.000000" y="0.000000" z="0.000000"/>
      <vertex x="41.500000" y="0.000000" z="0.000000"/>
      <vertex x="41.500000" y="41.500000" z="0.000000"/>
      <!-- ... more vertices ... -->
    </vertices>
    <triangles>
      <triangle v1="0" v2="1" v3="2"/>
      <triangle v1="2" v2="3" v3="0"/>
      <!-- ... more triangles ... -->
    </triangles>
  </mesh>
</object>

Manifold CSG Engine

Why Manifold ensures printable geometry:

Watertight meshes: No holes, gaps, or non-manifold edges
Exact arithmetic: No floating-point errors
Robust booleans: Unions and subtractions always succeed
WASM performance: Near-native C++ speed in browser

Manifold guarantees that every exported mesh is a valid, closed 2-manifold suitable for 3D printing.

Bambu Studio Integration

Optimized Metadata

The exporter includes Bambu-specific config files: model_settings.config

<config>
  <plate>
    <metadata key="plater_id" value="1"/>
    <metadata key="plater_name" value=""/>
    <metadata key="locked" value="false"/>
  </plate>
</config>

3dmodel.model (root element)

<model unit="millimeter"
  xmlns="http://schemas.microsoft.com/3dmanufacturing/core/2015/02"
  xmlns:p="http://schemas.microsoft.com/3dmanufacturing/production/2015/06"
  xmlns:BambuStudio="http://schemas.bambulab.com/package/2021"
  requiredextensions="p">
  <metadata name="Application">BambuStudio-02.05.00.66</metadata>
  <metadata name="BambuStudio:3mfVersion">2</metadata>
  <!-- ... -->
</model>

These metadata fields ensure Bambu Studio recognizes the file and opens it without warnings.

Coordinate System

Manifold uses Y-up (CAD convention), but Three.js uses Z-up (graphics convention). The export pipeline handles this:

Coordinate Transformation

// Swap Y ↔ Z when transferring Manifold → Three.js
for (let i = 0; i < positions.length; i += 3) {
  const y = positions[i + 1];
  positions[i + 1] = positions[i + 2]; // Y = old Z
  positions[i + 2] = y;               // Z = old Y
}

This transformation is automatic. Do not manually rotate models in the slicer—they will import with correct orientation.

Multi-Object 3MF Structure

Exporting all bins creates a multi-object 3MF:

Object Hierarchy

Each bin requires two objects:

Volume object (odd ID): Contains actual mesh
Parent object (even ID): References volume + adds name

<object id="1" type="model">
  <mesh><!-- vertices & triangles --></mesh>
</object>
<object id="2" type="model" name="Bin 2x3x4u">
  <components>
    <component objectid="1"/>
  </components>
</object>

Build Items

The <build> section lists all printable objects:

<build>
  <item objectid="2" p:UUID="a1b2c3d4-..."/>
  <item objectid="4" p:UUID="e5f6g7h8-..."/>
  <!-- ... one item per bin ... -->
</build>

UUIDs are auto-generated for each build item to ensure slicer compatibility.

Slicer Compatibility

Tested and working:

Bambu Studio

Full support:

Multi-object import
Metadata recognition
Auto-arrange on plate

PrusaSlicer

Full support:

Multi-object import
Instances and copies
Auto-arrange

Cura

Full support:

Multi-object import
Group operations
Per-object settings

Import Behavior

Bambu Studio: Opens with all bins on plate, ready to slice
PrusaSlicer: Imports all objects, may require auto-arrange
Cura: Imports as group, drag to separate if needed

File Naming Convention

Single bin: gridfinity-bin-2x3x4u.3mf
- Format: gridfinity-bin-[W]x[D]x[H]u.3mf
All bins: gridfinity-layout-2024-03-15.3mf
- Format: gridfinity-layout-[YYYY-MM-DD].3mf

Export Performance

Single Bin

Typical time: 0.5-1 second
Depends on divider count
Simple bins (<0.5s)

Full Layout

Typical time: 2-5 seconds
Depends on bin count
10 bins: ~3 seconds

Complex bins with many dividers take longer to generate. The Web Worker keeps the UI responsive during export.

Privacy & Security

Fully client-side: All geometry generation and 3MF packaging happens in your browser. No server uploads, no data collection.

No internet connection required (after initial load)
Your designs never leave your device
Works offline (PWA mode)
No file size limits

Troubleshooting

File won't open in slicer

Possible causes:

Browser canceled download (check download folder)
File corrupted during download (re-export)
Slicer version too old (update to latest)

Solution: Ensure the file size is reasonable (>1KB) and try a different slicer.

Bins appear at wrong position

This is expected—slicers may auto-arrange objects. Use the slicer’s “Arrange” function to optimize plate layout.

Missing bins in exported file

Cause: Only bins that successfully generate CSG meshes are included. Check the 3D preview for any wireframe placeholders (red boxes)—these indicate failed geometry.Solution: Simplify the bin (reduce dividers, avoid extreme dimensions) and re-export.

Tips & Best Practices

Test print a single bin first before exporting and printing an entire layout. Verify fit on your baseplate.

Group similar bins in your layout to take advantage of slicer’s “duplicate” and “arrange” features.

Check 3D preview before exporting. If a bin shows as a red wireframe, it failed CSG generation and won’t export.

Technical Implementation

Export module: src/gridfinity/export3mf.ts
3MF packaging: JSZip library
Mesh format: Manifold → TriangleMesh adapter
Compression: DEFLATE (ZIP standard)
XML generation: Template strings with escaping
UUID generation: Crypto-random hex (RFC 4122 v4)

3D Preview

Verify geometry before exporting

Bin Configurator

Configure bin parameters for export

Get Started

Core Features

Gridfinity Spec

Guides

Overview

Export Options

Export Single Bin

Export All Bins

3MF File Format

Format Structure

Why 3MF over STL?

3MF Advantages

STL Limitations

Geometry Generation Pipeline

Manifold CSG Engine

Bambu Studio Integration

Optimized Metadata

Coordinate System

Coordinate Transformation

Multi-Object 3MF Structure

Object Hierarchy

Build Items

Slicer Compatibility

Bambu Studio

PrusaSlicer

Cura

Import Behavior

File Naming Convention

Export Performance

Single Bin

Full Layout

Privacy & Security

Troubleshooting

Tips & Best Practices

Technical Implementation

3D Preview

Bin Configurator

Build docs developers (and LLMs) love

Get Started

Core Features

Gridfinity Spec

Guides

​Overview

​Export Options

Export Single Bin

Export All Bins

​3MF File Format

​Format Structure

​Why 3MF over STL?

3MF Advantages

STL Limitations

​Geometry Generation Pipeline

​Manifold CSG Engine

​Bambu Studio Integration

​Optimized Metadata

​Coordinate System

​Coordinate Transformation

​Multi-Object 3MF Structure

​Object Hierarchy

​Build Items

​Slicer Compatibility

Bambu Studio

PrusaSlicer

Cura

​Import Behavior

​File Naming Convention

​Export Performance

Single Bin

Full Layout

​Privacy & Security

​Troubleshooting

​Tips & Best Practices

​Technical Implementation

​Related Features

3D Preview

Bin Configurator

Build docs developers (and LLMs) love

Overview

Export Options

3MF File Format

Format Structure

Why 3MF over STL?

Geometry Generation Pipeline

Manifold CSG Engine

Bambu Studio Integration

Optimized Metadata

Coordinate System

Coordinate Transformation

Multi-Object 3MF Structure

Object Hierarchy

Build Items

Slicer Compatibility

Import Behavior

File Naming Convention

Export Performance

Privacy & Security

Troubleshooting

Tips & Best Practices

Technical Implementation

Related Features