Download VW Up! v baseplate as a free 3D printable phone mounts STL for Volkswagen up!. Made some openings where the mount grips this plate. I found it…
Print setup recommendations
Material: PETG or ASA
Infill: 20-30% infill with 1.2-1.6 mm walls
Supports: verify in slicer
Ensure a brim or raft is used for stability if necessary
Use a moderate to high adhesion setting for the print bed
Final orientation and support decisions should be checked in the user's slicer
A higher infill percentage may be needed if the baseplate will be subject to heavy stress