Create an interlocking block

Select the border of the workplane in the viewport. A Command Mini Toolbar (CMT) opens. The CMT displays relevant commands.

Click

on the CMT.

Draw a rectangle on the workplane.

Select the border of the workplane and Pull the rectangle (2D profile) into a 3D object. After pulling the profile to a 3D object, you can delete the workplane.

Don't forget to click

to complete each operation. Click View and then, in the Viewing group, click:

rotate,

pan,

or zoom for a better view.

Shortcuts:

1.		Watch video
2.		Select the lateral face of the 3D object and click on the CMT to draw a circle. A workplane is automatically created on the face.
3.		Draw four circles; the radius of each circle must be 20 units.
4.		Select the border of the workplane and Pull all four circles (2D profiles) into bosses (3D objects). After pulling the profiles to 3D bosses, you can delete the workplane.
5.		Select the top edge of a boss and create a constant radius blend with a radius of 1 unit.
6.		Select the edges of the remaining bosses to propagate the blend.