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Whip something up *fast*

Shape building

Drop primitives onto the grid, mark each as solid or hole, group them, and let Manifold boolean CSG fuse them into one watertight part.

Shape building is the core of CubbyCAD: you assemble a model out of simple primitives — boxes, spheres, cylinders, cones, and more — then combine them with boolean operations. Every shape is either a Solid (it adds material) or a Hole (it carves material away), so you can rough out a body and then drill, slot, and pocket it without ever leaving the parametric scene.

Reach for this whenever you want precise, editable geometry. Because shapes are combined with the Manifold engine, the result stays a clean, watertight mesh you can keep tweaking — change a primitive's size and the whole assembly rebuilds.

Shape building: various primitives

How to use it

  1. Add a primitive

    Drag a tile (such as Box, Sphere, or Cylinder) from the shapes palette and drop it onto the grid or an existing face. You can also run the command-palette command Add Box (or Add Sphere, Add Cylinder, etc.) to drop one at the origin.

  2. Position and size it

    Select the shape and use the move/rotate gizmo, or edit its dimensions (Radius, Height, and so on) in the Properties panel.

  3. Choose add or remove

    With the shape selected, open the Role section of the Properties panel and click Solid (adds material) or Hole (subtracts it). The same toggle is available as the Make solid and Make hole commands and in the Object menu.

  4. Group the shapes

    Select the shapes you want to combine, then choose Group (Ctrl/Cmd+G) from the Object menu or command palette. Grouping is what tells the app to run the boolean — holes inside the group cut the solids in that group.

  5. Inspect the result

    The group rebuilds automatically into a single combined body. Adjust any child primitive's parameters and the boolean re-evaluates live.

  6. Ungroup to undo

    To break a combination apart again, select the group and choose Ungroup (Ctrl/Cmd+Shift+G).

The Role section: Solid vs Hole
In the editor. A hole primitive cutting a solid inside a group, with the Properties panel’s Role toggle.

Tips

  • Booleans happen inside a group. A loose Hole sitting next to a Solid won't cut it — they must be children of the same group for the subtraction to apply.
  • The shapes palette has fuzzy search: type "cube" or "square" to find Box, "ball" for Sphere, "donut" for Torus, "ramp" for Wedge, and so on.
  • A new shape defaults to Solid; switch it to Hole whenever you want it to carve rather than add.
  • By default a group's combine Style is Sharp — exact, crisp boolean edges via Manifold. Switch it to Blended for rounded joins (see Smooth blends).
  • Turn on a group's Multicolor option to keep each part's own colour in the combined shape instead of one flat group colour — useful for coloured parts and required for colour export.

Try it in your browser

Open CubbyCAD and put Shape building to work — it runs in the browser, no install.

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