Repair, combine, and rebuild meshes.
Drop an STL, OBJ, or PLY mesh to heal it watertight, boolean-combine two meshes, or rebuild a surface from a PLY point cloud. Everything runs in your browser.
- .stl
- .obj
- .ply
About Mesh Fixer
Loft Mesh Fixer is a free in-browser mesh repair tool that turns a broken, open, or non-manifold STL / OBJ / PLY mesh into a watertight, manifold solid using signed-distance-field remeshing. It also boolean-combines two meshes (union, subtract, intersect) through a real CSG kernel with an honest result report, and reconstructs a watertight surface from a PLY point cloud via winding-number reconstruction. Everything runs locally in WebAssembly — no upload, install, or signup — so confidential CAD never leaves your device.
What it does
- One-click Heal — remeshes an open / cracked / non-manifold mesh into a watertight, manifold solid (SDF repair)
- Boolean combine — union, subtract, or intersect two meshes through a real CSG kernel
- Honest result report — volume, area, triangle count, component count, genus, and a watertight verdict
- Point cloud reconstruction — rebuild a watertight surface from a PLY point cloud (normals estimated if absent)
- Refusal is explicit — a boolean on a non-watertight operand tells you the open-edge count and to Heal first
- Chainable — heal a mesh, then boolean it, then export, without re-importing
- STL (binary + ASCII), OBJ, and PLY input; STL and OBJ export
- Shaded, shaded-with-edges, and wireframe display modes
- Runs entirely in WebAssembly — files never leave your device
- Works offline after the first visit (PWA cache)
How to use Mesh Fixer
Open a mesh
Drag an STL, OBJ, or PLY file into the browser, or click Open mesh and pick one. It loads instantly — nothing leaves your device.
Heal to watertight
Click Heal to remesh an open, cracked, or non-manifold model into a watertight, manifold solid. The result report shows the new triangle and vertex counts.
Boolean-combine (optional)
Open a second mesh as Mesh B, pick Union, Subtract, or Intersect, then click Combine. The report shows volume, genus, and whether the result is watertight.
Export
Click STL or OBJ to download the repaired or combined mesh.
Frequently asked questions
What does "watertight" mean?
A watertight mesh is a closed, manifold surface with no holes, no boundary edges, and no non-manifold edges — every edge is shared by exactly two triangles. Heal rebuilds your mesh to that standard so it is valid for 3D printing, boolean operations, and volume measurement.
Why was my boolean refused?
Boolean operations require both operands to be watertight solids. If an operand has open or non-manifold edges, the tool refuses rather than return garbage, and reports the open-edge count. Run Heal on that mesh first, then retry the boolean.
Will my file leave the browser?
No. Importing, repair, the boolean kernel, and reconstruction all run in your browser tab via WebAssembly. Nothing is uploaded to a server.
What formats are supported?
Input: STL (binary and ASCII), OBJ, and PLY (meshes and point clouds). Export: STL and OBJ. Point cloud reconstruction reads PLY points.
Can it rebuild a mesh from a scan or point cloud?
Yes. Load a PLY point cloud via Points → mesh and it reconstructs a watertight surface using winding-number reconstruction. If the PLY carries per-point normals they are used directly; otherwise normals are estimated.