I would like to use this for 3D printing. I often find that I need to go back and modify features because the size didn't come out correctly. Lets say a partial hole is formed by some boolean operation where the subtraction wipes out the tool.
My question is it possible to go back and modify sizes that are not shown in the final model? its seems inefficient to undo to that point & rebuild the model from there. so the question is how to you get around not having history?

I attached the model in question.

Hi dean, well if you want to make the hole larger you can just use a larger cutting object. If you want to make it smaller you can fill it in using untrim or boolean union and then redo the cut. Or on a simple shape like you have here just build a new one.

If making changes like this is something you need to do frequently then you might be better off with a parametric history based CAD program, there are a lot out there like SolidWorks, Alibre, OnShape, Solid Edge, etc...

MoI is not really intended to be a complete replacement for those types of programs, it's focused on other qualities like being easier to use and to have a more fluid drawing environment.

- Michael

thanks and I completely understand. Just checking to see if I missed anything.
I'm currently using Alibre which seems to work but has other limitations. just looking for something better suited to dimensionally accurate models for 3D prints.

I guess its about work arounds. Boolean make it easy to poke features in to the part and I'm impressed how this program works. the workaround could be to save a copy with tools in place so you can go back to that point in the design if needed. I'll keep playing with it.
Dean