I have read 'No Experience Required', but, not the 'For Dummies' title, though I know the author to be an exceptional tutorial writer for the programming titles and classes we've worked on together. They will both be good for beginners.
Now 'No Experience Required' is probably more architectural in flavor, so you could always find something more mechanically geared (I believe 'applying autocad' is, but, I like the other titles I mentioned better, even if they show more houses than mechanical parts).
If you're looking for mechanical as in manufacturing, you'll want Inventor or even Solidworks.
For mechanical as in HVAC/R, you'll want Revit MEP.
Melanie Stone
Facilities Data Management
IWMS / CAFM / CMMS / AutoCAD / Archibus / Tririga / Planon / MRI Manhattan CenterStone / Revit / data normalization, data mapping, reporting and process documentation
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