are you wanting to calibrate your actual X-Y output scale, or your sensors for reading registration marks...?
Also you have not said at all what software you are using, or exactly what problems with scale that you are having....and it really depends on software type...
if using Graphtec sofware plugin to adobe ( for example) using GPGL command mode, scale can be tweaked using "step size" as shown in section 3.2 of your Graphtec manual...
With software using HPGL command mode, you should have scale settings there, and plotter scale is also tweaked Using "Distance Adjustment" as explained in section 4.9 of your Graphtec manual...
it correlates and can be saved with condition settings....
it is a o.oo% percentage setting relating to +/_ mm gain or loss and calibrated separately for X and Y axis...(see step 7)
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