skip to content

Blender logoblender · HeyBraza shows you

blender boolean modifier not cutting

HeyBraza points at the operation dropdown, the object picker and the mesh cleanup steps that make booleans behave.

HeyBraza in a real session - not this exact fix.

a boolean needs a clean, closed cutter - doubled vertices, holes or flipped normals make it silently do nothing or carve the wrong side. clean the mesh first and the modifier just works.

or do it yourself

  1. 1select the object you want to cut (not the cutter), then modifier properties > 'add modifier' > 'generate' > 'boolean'.
  2. 2set the operation to 'difference' and use the eyedropper/object field to pick your cutter object.
  3. 3clean both meshes: edit mode, select all (a), then m > 'merge by distance' to remove doubled vertices.
  4. 4fix normals on both: still in edit mode with everything selected, press shift + n to recalculate them outside.
  5. 5make sure the cutter is a closed solid that fully passes through, then hide it (h) and apply the modifier via the dropdown > 'apply'.

let HeyBraza do this with you

HeyBraza is a tiny on-screen guide that points at the right buttons and talks you through it, on windows and mac.

download

common questions

why does the boolean cut the wrong part away?

the cutter's normals are inside-out - select it, edit mode, a, shift + n, then try again.

do i have to hide the cutter object?

yes, or it renders on top of the cut. press h with it selected, or move it to a hidden collection.

more fixes