I don't understand the "middle of the page" - just eyeball it!
Depends on your CAM software. What filetypes does your CAM software accept?
Most will accept dxf if not ipt or stp.
File>Save Copy As type.....
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It sounds like you have not yet created a 2D drawing (*.idw or *.dwg) of the 3D model.
File>New and select appropriate *.idw template.
I recommend that you go through the Tutorials.
http://home.pct.edu/~jmather/SkillsUSA%20University.pdf
http://inventortrenches.blogspot.com/p/inventor-tutorials.html
http://wikihelp.autodesk.com/enu?adskContextId=HELP_TUTORIALS&language=ENU&release=2014&product=Inve...
CAM software (Computer Aided Manufacturing) creates machine toolpaths CNC-Computer Numerical Control (otherwise known as g-code) from your solid geometry.
http://cam.autodesk.com/inventorhsmexpress.php
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Inventor uses 3D models to create 2D drawings. You should spend time reading the links posted by JD
@Buhtwhai wrote:
...I have made a 2d drawing
Attach your 2d "drawing" file here.
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