Type XXI submarine model whose source proposes printing the interior hollow and making modifications to convert it into an RC. This is a base for a naval modeling project, not a complete or dive-ready remote-controlled submarine. No waterproofing, ballast, propulsion, diving mechanisms, or electronics are documented.

Preparation, compatibility, and printing

Study the file before deciding how to split or hollow it. A printed hull does not guarantee water-tightness, and any transformation must be developed as a separate project. Keep copies of the originals and first define how to access the interior and check joints. No materials or printing settings are documented; no inferred ballast or depth values are added.