To add a new custom paper size starting
from an existing paper size
ClickFile
menu Plotter Manager.At the Command prompt, enter
plottermanager.
In the Plotter Manager, double-click the plotter configuration
(PC3) file you want to edit.
In the Plotter Configuration Editor, Device and Document
Settings tab, double-click User-Defined Paper Sizes &
Calibration to display the calibration and paper size
settings.
Select Custom Paper Sizes.
Under Custom Paper Sizes, click Add.
In the Custom Paper Size wizard, Begin page, select Use
Existing.
In the list of existing standard paper sizes, select a paper
size on which to base the custom paper size you are creating.