Model a printable part, nothing to install.
Build parts from basic shapes like a construction set: solids add, holes cut, grouping makes them one part. Everything runs on your computer with manifold-3d, so what you export is always a closed solid, ready to slice.
Shapes
From the tools
Built by the same code as each tool's own page, and editable in Properties. Pick a gear and press “Add a mating gear” to build a pair or a whole train; racks and planetary sets are on the gear generator page.
Loading the modelling kernel…
Drag to orbit · scroll to zoom · right-drag to pan
Properties
Pick a shape on the left to add it, or click a part to edit it. Hold Shift while clicking to select several.
Saved automatically in this browser. Use “Save project” to take it to another computer.
Keyboard shortcuts
T / R / S — move / rotate / scale H — toggle solid ↔ hole D — drop to bed · F — set on a face · M — measure 0 — 3D view · 1 / 2 — front / back · 3 / 4 — left / right · 5 / 6 — top / bottom · Z — fit Arrows — nudge in X, Y · PageUp / PageDown — in Z · hold Shift: ×10 Ctrl+D — duplicate · Ctrl+G — group · Ctrl+Shift+G — ungroup Ctrl+Z — undo · Ctrl+Shift+Z or Ctrl+Y — redo Ctrl+A — select all · Esc — deselect · Delete — delete
How it works
Solids add, holes subtract.
Every part on the bed is a basic shape, an imported file or a group. Grouping unions every solid in the group, then subtracts every hole — the way Tinkercad works. A group is a part too: it can be made a hole, duplicated, or grouped again with others. A hole standing on its own cuts nothing yet, so it is not exported.
Union and subtraction run on manifold-3d, a kernel that always returns closed solids, so exported parts need no repair. Imported STL or 3MF files go through the same repair as /tools/mesh-fix: holes filled, flipped faces turned, overlapping shells merged. Every top-level part becomes its own object in the 3MF, in its own colour.
Checked: ten shapes with 12 random parameter sets each — every one closed, on the bed and centred. And 60 assemblies of a box, a cylinder hole and a sphere: the group's volume came out exactly box minus hole plus sphere, and after ungrouping every part sat where it had been, even with the group turned and moved. Over 200 random sketches, an extrusion's volume equals area × height and a revolve's matches Pappus's theorem within 1 %; in 300 set-downs on surfaces at random angles, each part touched the picked point without sinking in. For 80 random gears (spur, helical, herringbone, with hubs and lightening holes, some stood on edge), the gear from “Add a mating gear” cleared the first at rest and collided once turned past the backlash.
How is this different from Tinkercad?
The same solids-and-holes idea, but it runs entirely on your computer: no account, no upload, the project saved in your browser or as your own file. Imported files are mesh-repaired automatically, and ZORVA's generators are built in: QR codes, gears, Gridfinity, trays, name tags, lithophanes. In exchange, it has no dimension constraints in sketches, no text bent along curves and no community library yet.
How does a sketch work?
Press Sketch, draw an outline on the millimetre grid (or take a preset), then pick Extrude — pull the outline up into a solid, optionally twisted or tapered — or Revolve it round the axis for a vase, a cup or a knob. The outline can be redrawn any time from Properties.
How do I build a gear train?
Add a Gear and set its teeth, module, helix, hub and bore in Properties. Type the next gear's teeth and press “Add a mating gear”: the new gear lands at the centre distance, its teeth in phase and twisted the other way. Pick the new gear and repeat for a whole train. Moving or turning a gear afterwards takes it out of mesh — delete it and add it again.
How do I make text or a QR code a different colour from its plate?
QR codes, name tags and trays come with a colour for each element: plate, code, caption, letters, lid. For your own lettering, add a Box as the plate and a Text, set the text on the plate (or sink it in a little), select both and press Group: the new group keeps each part's colour. Export 3MF and every colour is a part of one object with its own filament, which Bambu Studio, OrcaSlicer and their kin read straight in for a multicolour printer (AMS…). Untick “Keep each part's own colour” for a group in one colour.
How do I cut a hole through a part?
Add a cylinder, press Hole, make it longer than the part and place it where the hole goes. Select both (hold Shift), press Group. For an M3 bolt make the hole 3.2–3.4 mm: printed holes usually come out a little small.
Where is my project saved?
Automatically, in the storage of the browser you are using (IndexedDB), so a reload keeps it. Clearing the browser's data or moving to another computer loses it — press Save project for a .json file you can open anywhere.