Menu: Edit / Eraser
In this menu you will be able to activate the "Eraser" by clicking 
. You can drag the eraser around with your mouse, it will move on the plan dictated by the view. You can choose between a "Cubic" or "Spherical" shape, and then decide on the "Size" and "Opacity".
The "Size" will be the radius of "Spherical" and the length for "Cubic".
Press"D" to erase and "R" to restore
