Combine shapes (booleans)

Union, subtract, or intersect selected solids.

Booleans are non-destructive: the result remembers its inputs, so you can ungroup to get the original shapes back and re-edit them. The Combine menu collects all of these operations.

Selection order decides what a Subtract keeps. The first shape you click is the body; everything selected after it is a cutter. Get it backwards and the body is what gets cut away, which usually looks like the model vanishing — the toast that appears after a Subtract names the shape it kept and offers a one-click Flip to reverse it. Union and Intersect do not care about order.

Selecting many shapes is quicker in the scene tree than in the viewport: click the first row and shift-click another to take the whole run between them, which is the fast way to subtract a whole imported drawing from a plate. Ctrl-click (⌘-click on a Mac) toggles a single shape in or out without disturbing the rest, and the row you last clicked plainly — without shift — is where the next range measures from.

1. Select two or more overlapping shapes — for a Subtract, click the one you want to KEEP first.
2. To pick up a run of shapes, click the first and shift-click the last; ctrl-click (⌘-click) adds or removes one.
3. Open Combine and choose Union, Subtract, or Intersect.
4. Ungroup later to recover the originals, or Split a body into its parts.