Add pipes, mounts, and ducts to any STL in 5 minutes – no CAD needed.
STL ExtrudeLab lets you load existing 3D meshes (STL, OBJ, PLY, GLTF), select a surface, and build clean extensions like pipes, brackets, and connectors – all in your browser. Perfect for 3D printing hobbyists who want to adapt downloaded models without learning complex CAD software.
Everything you need to extend meshes
Focused tools for extending existing meshes – not a full CAD system, just what you need to adapt and tweak STL files for 3D printing.
Screenshot Needed:
File import dialog showing drag-and-drop area with supported format icons (STL, OBJ, PLY, GLTF/GLB).
Load STL, OBJ, PLY, or GLTF/GLB models. Everything is converted into a unified mesh format that you can work with directly in the browser. Supports files up to 50MB.
Screenshot Needed:
3D model with selected faces highlighted in blue/green, showing the face selection UI with click-to-select functionality.
Click to pick surfaces, extract edge loops automatically, and tweak them with simple edge editing so your extensions start from a clean, precise boundary.
Screenshot Needed:
Model with 2-3 visible waypoints (colored spheres/markers) showing a curved pipe extension being generated along the waypoint path.
Add one or more waypoints to control direction, length, and curvature. Create straight pipes, 90° elbows, or complex curved paths with just a few clicks.
Screenshot Needed:
Mesh simplification slider showing before/after face counts (e.g., "50,000 faces → 10,000 faces") with visual comparison.
Simplify heavy meshes with a single slider to improve performance. Run integrity checks to spot issues like non-manifold edges and get automatic repair suggestions.
How it works
The workflow is intentionally simple – import, select, extend, export. Most projects take under 10 minutes.
Screenshot Needed:
Freshly loaded STL model centered in viewport with file info panel showing format, face count, and file size.
Drag in an STL, OBJ, PLY, or GLTF file. The tool automatically loads and validates the mesh. Optionally run mesh simplification for smoother interaction on complex models.
Screenshot Needed:
Model with selected region highlighted, boundary loop detection panel showing "Outer loop: 24 points" with preview of extracted boundary.
Click faces to select the area you want to extend from. The tool automatically detects boundary loops. Fine-tune edges if needed to get the exact start shape you want.
Screenshot Needed:
Complete extended model with pipe/mount attached, showing waypoint controls and "Export STL" button highlighted.
Place waypoints to shape your extension. Preview in real-time, adjust parameters like diameter and rotation, then export the complete merged mesh as STL ready for your slicer.
See it in action
Watch how easy it is to extend an STL model from start to finish
Screen recording showing: (1) Importing an STL, (2) Selecting faces and detecting boundary, (3) Adding 2 waypoints to create a curved pipe extension, (4) Exporting final STL. Include narration explaining each step.
Why STL ExtrudeLab?
Built specifically for extending existing STL files – faster and easier than general-purpose 3D tools
| STL ExtrudeLab | Blender | Fusion 360 | Tinkercad | |
|---|---|---|---|---|
| Learning curve | ✓ 5 minutes | ✗ Hours | ✗ Days | ✓ 10 minutes |
| Browser-based | ✓ Yes | ✗ Desktop only | ✗ Desktop only | ✓ Yes |
| Mesh extension | ✓ Built for it | ✓ Complex | ✗ Parametric only | ✗ Basic |
| Waypoint control | ✓ Visual & simple | ✓ Advanced | ✓ Sketch-based | ✗ No |
| Installation | ✓ None | ✗ Required | ✗ Required | ✓ None |
| Price | ✓ Free | ✓ Free | ✗ $70/mo | ✓ Free |
Who is this for?
STL ExtrudeLab sits between Tinkercad and full CAD – easy to learn, but powerful enough to be genuinely useful.
Adapt files from Thingiverse, Printables, or other sources by adding mounts, supports, and extensions. "I downloaded a wall mount but needed a cable routing arm – MeshExtend saved me hours of CAD frustration."
Customize parts for your specific hardware setup: extra brackets, longer arms, cable guides, and one-off tweaks. Perfect for robotics, home automation, and workshop projects that need unique adapters.
Make quick mesh-level changes between revisions without parametric models. Extend existing prototypes, test fit variations, and iterate faster without going back to CAD every time.
Open STL ExtrudeLab in your browser, load a model, and try extending a simple surface. No account, no installation, no hassle – just the tool you need to adapt STL files for 3D printing.
Use ExtrudeLab in Browser – Free ➜