See the attached. Or just try by yourself: draw a cube in ACAD, switch to an ISO view, print out at 1:1 scale, measure it on paper. Think about this case: a circle in ISO view is an ellipse. How can the dimensions of an ellipse are the same as those of a circle?
@caronte01 said:
In isometric, you should get real dimensions. Lines on the x, y and z direction should be to scale(1:1). There´s probably a bug in 2d iso export that will export isometrics at .8 ish of the correct scale. I´ve also had it. The solution has been to scale with reference in acad the exported dwg.
S