Hi,
In the plot dialog box, on the Plot Settings tab, there is an option to set the plot scale. There's a drop list to select a predefined scale or input a custom scale as well as a Scale To Fit option..
To make sure that viewports have the correct scale, simply select the viewport border and go to Tools >> Properties. In the properties box, look for the scale section and select a scale. Alternatively, you could have the viewports toolbar showing on your screen and when you double-click inside the desired viewport (so that you're in floating modelspace), simply select the desired scale from the drop list in the toolbar..
I hope that this helps..
Cheers,
Paul @ basepoint designz..
basepoint designz
renegade@tiscali.co.uk