I there a way to save a 2018 version file to an earlier version?
The only way to do it is to save the file as a non-sw file like a stp file. The best choice is to save it as a parasolid as that is the native file format.
For drawings, DWG suffices but font, property, and other detail disconnects will occur. PDF is about equal, as it only makes vector lines on page.
I'd stick to the parasolid of a part or assembly like Jim mentions, then make a new drawing instead of trying to carry future version back.
Thank you all.
If it is a drawing... no. A model can be taken to other formats as Jim mentions, although I would prefer a Parasolid since SW is built on that kernel.
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