Hi Gerry - it is possible to enter accurate dimensions when you are drawing things.

Like for example if you want a rectangle of a specific width and height, you can enter those dimensions in the Width: and Height: options that show up in the options area in the upper-right corner of the screen.

Also when you are entering points like when you are drawing a line, you can enter specific x,y,z coordinates, and you can also enter a distance for the second point of a line or angle using the controls in the bottom toolbar (just to the right of the Split / 3D / Top / Front / Right view control tabs).

But for version 1.0 there is not any option to draw dimension annotations like you would see in a blueprint (with a number and some arrows pointing out from it). That is definitely something that I would like to add in the next version though.

However, they will mostly be used as a kind of annotation or labeling system, not really as a way to control objects.

Some other CAD systems do use those kinds of on-screen dimensions to control objects (like a constraint-based CAD system) - MoI is not really intended to work in that exact same way. If you need to specify and change a lot of constraints like that, you will probably be better off in one of those systems that is designed more specifically for that kind of operation like SolidWorks, Alibre, Pro/E, etc...

- Michael