If you're unable to find a free version, consider reaching out to Autodesk's customer support or checking if there's an option to purchase the documentation or a user guide directly from them.
If searching for the "ArtCAM 2018 Manual PDF" leads to dead ends, consider these alternatives: Artcam 2018 Manual Pdf
Users who had an active subscription or maintenance plan in 2018 were given access to the "Autodesk ArtCAM 2018" download portal. If you still have your login credentials, you can access the "Documentation" tab in your Autodesk Account under "Products & Services" > "Previous Versions." If you're unable to find a free version,