Updated for Blender Version: 3.1
To the Point
- In Object mode, select the object on which to apply the Boolean
- Navigate to the Modifiers tab in the Properties Panel
- Click the “Add Modifiers” dropdown and select Boolean
- On the right side of the Boolean settings, click the Object box to select the second object to use in the Boolean operation (select it either by the drop-down or with the eyedropper tool)
- Select the desired Operation from the dropdown
Optional:
- Select the second object in the Boolean operation
- Navigate to the Object tab in the Properties Panel
- Scroll down to Viewport Display
- From the “Display As” drop-down, select “Wire”
The Details
The boolean is an extremely useful tool when modeling complex objects. There are a few options for what a Boolean can do to two objects: it can either show the difference of two overlapping objects, the intersection of two overlapping objects or join two objects together into one mesh. Joining two objects with Booleans is a bit different than other joining or merging methods.
To start with, you need two objects – a primary object on which the Boolean modifier will sit, and a secondary object – the object that overlaps the primary object. Here’s a simple example. The highlighted cube will be the primary object, and the sphere on top is the secondary object. Click on the primary object, and go to the Modifiers tab in the Properties panel.
Click the Add Modifier dropdown and select Boolean. From here, we need to tell it what object we want to use in the operation (in our example, we want to select the sphere). On the right of the Boolean box in the Modifiers panel, click the white square on the Object drop-down to select an object from a list, or simply use the eyedropper tool to pick the object.
To help see what’s going on here, select your secondary object. Navigate to the Object tab in the Properties panel.
Scroll down and find Viewport Display, click the “Display As” drop-down and select “Wire”. You will now see what’s really happening with the Boolean operation. To do any further modeling to the affected object, the Boolean modifier must be applied.
Settings
Now that you can see through your secondary object, you can see the effects it has on the primary object.
Intersect
The intersect setting will only display the portion of the object where both meshes overlap.
Difference
Difference will show everything on the primary object except what is overlapped by both meshes.
Union
Union will merge both objects. To see the complete effect, make sure you click “Apply” once the objects are in place. Then you can go into edit mode and see both meshes fused together as one.