I didn't use Blender, but the way I understood it, it is more like modelling. Opposed to that, Inventor is technical drawing. E.g. I could: Draw 2D plane 10x10

I didn't use Blender, but the way I understood it, it is more like modelling. Opposed to that, Inventor is technical drawing. E.g. I could: Draw 2D plane 10x10 mm; extrude; on one surface, create a diagonal helper line; put three circles on that line; define diameter of one circle to be 2.5mm; constraint diameter of the other circles to be equal to the first; split the helper line at every circle intersection; constrain all line segments to be equally long - now all things are fully constrained. Negative extrude the circles (e.g. make holes into the first volume). Should produce something like this: *---* |o | | o | | o| *---* You can now change values (e.g. make the base plate 20x50mm and adapt the diameter to 4mm) and the program will keep rearrange everything according to the constraints, if possible.