FuMesh
Early accessVersion 0.1.1: Combine's seam blend now works on detailed parts. → A mesh editor for fixing 3D models

Fix the mesh. Print the part.

FuMesh fixes 3D models and gets them ready to print, without the weight of a full CAD or 3D suite. Close holes, remove loose pieces, clean up bad triangles and smooth rough surfaces, cut, sculpt and combine parts, then check that a slicer will take it.

Download for Mac dmg · 177.1 MB Windows and Linux
macOS on Apple siliconWindows 10 / 11Linux x86-64STL · OBJ · PLY · 3MFWorks offline
The FuMesh window with a model of a French bulldog that has five holes and three loose pieces floating beside it. The Auto Repair panel shows a dry run: the loose pieces would be removed and all five holes closed, and a before and after table says the model would go from four parts and five holes to one watertight part.
Auto Repair's dry run on a model with five holes and three loose pieces: what it would do, before anything changes.
Download

Version 0.1.1

— downloads— visitorscounted once the page is on stigern.net

This is early access, shared as is. FuMesh is free and open source, with no account and nothing to sign up for. The Mac app is signed and notarized by Apple. The Windows builds are not signed, so Windows asks once before the first start (see below).

macOS

Apple silicon (M1 and later). Tested on macOS 27; parts of it are built for macOS 26, so older versions may not start it. Open the disk image and drag FuMesh to Applications.
FuMesh-0.1.1-macos-arm64.dmg177.1 MB
Download

Windows

Windows 10 or 11, 64-bit. Installs for your own user, or for everyone if you run it as an administrator, and adds FuMesh to “Open with” for STL, OBJ, PLY and 3MF.
FuMesh-0.1.1-windows-x64-setup.exe110.2 MB
Download

Windows, as a zip

The same app without an installer: unpack it anywhere and start FuMesh.exe.
FuMesh-0.1.1-windows-x64.zip174.0 MB
Download

Linux

x86-64, glibc 2.43 or newer: Ubuntu 26.04, Fedora 44 or later. Runs on Wayland and X11. A desktop file and icon are included, with INSTALL.txt.
FuMesh-0.1.1-linux-x86_64.tar.gz236.8 MB
Download

Source code

Everything needed to build FuMesh yourself, under the GNU GPL v3.0.
FuMesh-0.1.1-source.tar.gz6.2 MB
Download
SHA-256 checksums
5699dae1ea3cc2be9d53d3393a42d32f9a735c922ad57ab66e647294995dea53 FuMesh-0.1.1-macos-arm64.dmg
17767929ff503fd9be71891035c476e762cb4479bbf27fa57fe30442002c508b FuMesh-0.1.1-windows-x64-setup.exe
ba18a7e74944ce4a375bdee6f02e62e60c3a553a95bc9c21a7bef188964da73e FuMesh-0.1.1-windows-x64.zip
5a71819237bb0755ce75f57d1dedfab66be116feb74554c9db2ccc4a72a30f94 FuMesh-0.1.1-linux-x86_64.tar.gz
600ce38e72889b23ae38f144768ce1f3d04154eea464d084178278d8bde5e3a7 FuMesh-0.1.1-source.tar.gz
SHA256SUMS.txt

Windows: the first start

SmartScreen says Windows protected your PC; choose More info, then Run anyway. The Mac app opens without asking: it is signed and notarized by Apple.

Linux

Unpack it and start FuMesh in the folder. INSTALL.txt says how to add it to your menu.

tar xzf FuMesh-0.1.1-linux-x86_64.tar.gz

Free. What is in this version is in the changelog below. If it saves your print, you can buy me a coffee.

☕ Buy me a coffee
Getting started

Open, fix, export.

Step 1

Open a model

STL, OBJ, PLY or 3MF, from a download, a CAD export, a sculpt or a scan. Drag the file onto the window; FuMesh asks for the units when the file doesn't say.

Step 2

Fix it

Auto Repair closes the holes it is sure about, removes loose pieces and cleans up bad triangles. Run it as a dry run first to read what it would do, or use the tools one by one: Fill Holes, Islands, Clean Up, Smooth.

Step 3

Check and export

Print Check shows what a slicer would trip over. Export STL or 3MF for printing, or save a .fumesh project to keep working later.

The Fill Holes panel beside a bulldog model with five holes. Each hole has its own colour in the list and the view, with its perimeter, area and shape, flat or curved, and the panel offers a flat patch or a curved fill.
Fill Holes lists every hole with its size and shape, coloured to match the view. Flat or curved fills, previewed first.

Every change shows first, and undoes

Each tool explains what it found and shows a preview before it changes the mesh. Every change can be undone with ⌘Z or Ctrl+Z, and colours or UVs are never dropped without asking.

Projects save the whole scene with units and placement. Autosave keeps your work, and after a crash FuMesh offers to bring it back.

Tools

What a mesh usually needs, and not much more.

RepairClose holes (flat or curved), remove loose pieces, clean up bad and duplicate triangles, fix self-intersections, or all at once with Auto Repair
Cut and placePlane cuts with caps, split, lasso and brush selection, transform, lay flat, drop to bed
SculptSmooth, flatten, move, inflate and deflate brushes, with masks
CombineUnion, difference and intersection; Auto-Fit lines up two overlapping scans
Smooth and tidySmooth rough surfaces, Reduce heavy meshes, Remesh into even triangles, each with a preview and how far the surface moved
SolidsMake solid, Hollow with drain holes, Thicken, Text, Compare
MeasureThe size of a part, and the distance between two points on it

FuMesh is made for the meshes you have: a download that won't slice, a CAD export with gaps, a sculpt with loose bits, or a scan. It fixes what is wrong and keeps the rest of the surface as it was.

Heavy work runs in the background, so the window stays responsive on meshes of millions of triangles, and a running job can be cancelled.

Booleans use Manifold, so unions and cuts of closed parts give closed results.

The Print Check panel beside a bulldog model with three loose pieces. It reports one problem to fix, an open surface with three holes, and two to review, a non-manifold vertex and three tiny loose parts, each with a Show button and, where there is one, a button for the tool that fixes it.
Print Check sorts what it finds into what to fix and what to review, and points to the tool that fixes each.
3D printing

Know it will slice before you send it.

Print Check looks for open edges and holes, non-manifold edges, flipped triangles, loose parts, self-intersections, walls thinner than your nozzle can print, and whether the part fits your build volume.

Units are kept from import to export: an inch-sized STL stays an inch, and 3MF files carry their units and placement.

In numbers

Tested on all three systems.

18toolsPanels for repair, editing, combining, solids and printing
4formatsSTL, OBJ, PLY and 3MF, plus FuMesh's own project files
1,081testsRun on macOS, Linux and Windows before this release
14checksIn the built-in self-test, passed by every package: FuMesh --self-test
Private

Your models stay on your computer.

FuMesh works offline. It needs no account and no online service, and it sends nothing anywhere.

  • No internet connection is needed for anything: repair, editing and checks all run on your own machine.
  • No account, no sign-up, no tracking in the app.
  • Free software under the GNU GPL v3.0: you may use it, study it, share it and change it. The source is in the download list.
  • Help → About lists every package FuMesh is built on, with its license.
Early access · a note from the author

Made with Claude, for my own models and prints, shared as is.

I wanted a simple tool to fix models before printing them, without learning a full 3D suite. The code was written with Claude. I take no responsibility for what it does to your files or machines: no warranty, no support promise. It works for my models and prints, and that is why it is here. This is an early version, so expect bugs and rough edges, and keep a copy of anything you can't afford to lose.

Changelog

What changed in each version.

Version 0.1.1

2026-11-03

A small update, still early access: Combine's seam blend now works on finely meshed parts.

Fixed

  • Smooth blend on finely meshed parts. Joining two detailed parts used to be refused, or blended only part of the way with a jagged seam, the more so the finer the mesh or the smaller the radius. The blend now goes all the way.
  • Adaptive join works in more of those cases, though not yet all: with very fine meshes and a wide band it can still refuse and keep the sharp join.
  • Print Check and the joins no longer report crossings that aren't there when two triangles lie in the same plane or along a thin shell.

Changed

  • Help → About has a Buy me a coffee button and links to this page.

Version 0.1.0

2026-11-03

The first release, for macOS on Apple silicon, Windows x64 and Linux x86-64. Before it, a bug hunt and its follow-up fixed more than 90 problems.

In this version

  • Repair: close holes flat or curved, remove loose pieces, clean up bad triangles, fix self-intersections, or Auto Repair with a dry run.
  • Editing: plane cuts with caps, split, lasso and brush selection, transform, lay flat and drop to bed.
  • Sculpt: smooth, flatten, move, inflate and deflate brushes with masks.
  • Combine: union, difference and intersection with Manifold, seam blending, and Auto-Fit for lining up two scans.
  • Optimize: Reduce, Smooth, Remesh and Make solid, each with a preview and an error report.
  • Solids: Hollow with drain holes, Thicken, Text and Compare.
  • Printing: Print Check, units from import to export, STL, OBJ, PLY and 3MF.
  • Projects: .fumesh projects with autosave and crash recovery.

Known issues

  • The Windows packages are unsigned, so SmartScreen asks before the first start.
  • The Mac package is for Apple silicon only, and has only been tested on macOS 27.
  • The Linux package needs glibc 2.43 or newer, so older distributions such as Debian 13 can't run it.
  • The seam blend in Combine can give up on finely meshed parts and fall back to a sharp join, with a warning. Fixed for Smooth blend in 0.1.1.
  • Compare and the adaptive seam blend are slow on large meshes: several seconds or more.