Subtract for Holes and Cutouts

Subtract is the most useful boolean for practical modeling.

Creating a Hole

To make a hole through an object:

1. Create your main shape (e.g., box)
2. Add a cylinder where you want the hole
3. Make cylinder penetrate both sides
4. Select box first, then cylinder
5. Click Subtract

Result: Box with cylindrical hole through it!

Selection Order

Critical for subtract:

• First selected = Shape to keep


• Second selected = Shape to cut away

Wrong order = wrong result!

Practical Examples

Drilled Holes

• Box + Cylinder = Hole
• For screws, cables, decoration

Cutouts

• Box + smaller Box = Window/door cutout
• For architecture, electronics cases

Carved Details

• Base + detail shapes
• For grooves, slots, recesses

Tips for Clean Subtracts

1. Tool should extend past surface

- Cylinder should poke out both sides - Avoids thin artifacts

2. Keep it simple

- One cut at a time - Easier to troubleshoot

3. Check from all angles

- Orbit to verify the cut - Look for unexpected results

4. Name your results

- "Block_With_Hole" - Helps track what's what

Common Uses in 3D Printing

• Screw holes
• Cable management holes
• Interlocking joints
• Lightening cuts (remove material)