dont forget, when you print there can be up to 5mm difference over each metre of paper variation - just due to the humidity of the paper, something that a lot of perfectionists in the architectural world seem to forget when claiming drawings are 'to scale' I dont know of any printer manufacturer that claims better accuracy. It can be done better but only with a full calibration run just before the required print, even then if you move the print to a more humid location, you stand the chance it will stretch by up to the same 5mm from true.
on some machines they express it as a scale when printing or copying, so 113% would equate to 1.13 as a scale.
Grendel