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Fix non-manifold edges, holes, flipped normals, and loose geometry in STL, OBJ, PLY, GLB, and 3MF files. Free, in your browser, no upload.
Files are processed entirely in your browser. Nothing is uploaded to a server.
Any 3D edit is just a prompt away.
Attach an STL, OBJ, PLY, GLB, or 3MF file above and press "Repair it". The tool welds duplicate vertices, re-orients flipped triangles, closes small holes, and optionally deletes loose debris shells. Those four defects cause most "non-manifold" slicer errors. Everything runs locally in your browser, so your model never leaves your computer.
When the badge turns green ("Watertight, ready to print"), the mesh is a closed solid that Cura, PrusaSlicer, Bambu Studio, and Orca will all accept without complaints.
GrandpaCAD turns a text prompt into a ready-to-print 3D model. Functional parts, organic shapes, multi-color prints. No CAD skills needed.
"Model a watertight 32 mm replacement cooker knob with a D-shaped shaft hole and a knurled grip."
