Hi Andy, you might try using DXF export instead of PDF for this, it may be a bit easier since the DXF data will be 2D entities but won't be constrained to have the active viewed area limited to a printed page boundary like is implied with PDF files.

> I tried to use the CPlane thinking that it would reorient the coordinate system to
> selected geometry, but the exported geometry dimensions were scaled down.

The scaling can be turned off if you use the "Scale : Preserve units" option rather than "Scale : Fit to page":



With the default "Scale : fit to page " option, the generated output will be scaled and positioned so that it is centered on and fills up the PDF printed page extents. You can use "Scale : Preserve units" to avoid that from happening and instead control the mapping for conversion of units in MoI to units on the printed page. You will run into one other problem with doing that though which is that positioning is also turned off and your 2D output will have the world 0,0,0 point in MoI mapping to the 2D page lower left origin, that can mean that your objects although at the desired scale are located some long distance away from the visible page boundaries. In the future I want to add some options to control where the page origin will be taken from to make this easier.

In the meantime you may instead want to use DXF format which will do the same thing but whatever reads in the DXF will probably be able to zoom to fit the data inside of it and won't be so focused on only viewing just the printed page area as you will tend to get with PDF.

You could also do a post processing step on the PDF output to move it to a better origin point - to do that use File > Open to open the PDF file in MoI, MoI will zoom to fit so you'll see the output in the Top view. Now select all, run Transform > Move, click the base point at the lower left in the top view so it is just below your curves, then type in 0 and push Enter to move it to the 0,0,0 origin spot and then re-export it.

Another reason why you may prefer DXF format is that DXF can contain entities like exact circles, unlike PDF where there are only Bezier curves for everything.

- Michael