When a viewport is selected, a padlock icon appears to the left of the viewport scale button. Lock the viewport scale.
Specify the printer you want to use, its paper size, and so on, but leave the Plot Area drop-down list set at Layout. The first step is to define the paper, and the second step is to define the viewport or viewports. You thus can have multiple layouts or multiple page setups or both in one drawing.
Click Close to apply your new setup to the current layout. The New Page Setup dialog box appears. The instructions below explain how to re-scale a drawing from metres to millimetres. The new paper size is a user-defined size, not a standard size. You can add more layouts to the drawing, and each layout can have many viewports.
If you are creating a paper size that is larger than the paper sizes offered in the Custom Paper Size wizard, verify that the plotter is capable of plotting the new dimensions.
Note: Each plotter has a maximum printable area determined by where it grips the paper and how far the pen shuttle reaches.
A viewport is an actual drawing object. On the layout page, delete the existing Viewport to give you a blank page.