Can someone help me on creating or adding a scale in the plotter menu of version 10?
Hello & welcome!
It's just about the same way it works in any version since v5!
Go to Settings\Edit Defs\Scales\Change, select a scale that you will no longer need for this file.
It then prompts you to enter the way it will show up in the menu -- so 1:40 or 3/32" or what ever.
It then needs you to enter the factor for the scale -- this is the results of the scale as an equation. So for example, 1/4" = 1'-0" or 1/4" = 12", then .25"/12"=0.02083333333333... The trick is to either use a feet/inch calculator or convert each side to the same unit, and then do the math.
If you did it right, then the new scale should be listed in the correct position. Also, if you have any MSP details set up, then this may affect the scales that you used for them -- worst case is you have to select each detail and Page Up/Down once and then right-click to place it back where it was.