Flash CS3 Tutorial
How to Erase Shapes, Objects and Bitmapped Images in Flash
The Eraser tool in Flash works with Merge Objects, Drawing Objects and broken apart Bitmapped Images (Modify > Break Apart).
Add a rectangular object to the workspace with the Rectangle tool (r key).
Select the Eraser tool (e key) and click and drag across the object.
To erase with horizontal or vertical lines, press and hold the Shift key.
At the bottom of the Tools panel are the Eraser tool options.
With the Eraser Mode menu, you can choose to erase Normal, Fills, Lines, Selected Fills or Inside.
The Faucet option allows you to erase large sections.
The size and shape are set in the Eraser Shape menu.