Trieste the bathtub bathyscaphe (submarine)

thingiverse

This is the bathtub version of the famous batyscaphe Trieste. The original Trieste was the first manned submarine to dive to the deepest point of the earth, the Mariana trench. The Trieste was filled with fuel, which has a lower density than water. To be able to dive, the Trieste had iron weights that were dropped to resurface. You can see this nicely on the Wikipedia page: [Trieste](https://en.wikipedia.org/wiki/Trieste_(bathyscaphe)). The bathtub playboat version works very similar, it needs to be filled with water. It has two weights that are filled with metal (coins or fishing led) and that can be dropped and the little Trieste will reappear :) Printing and assembly need a bit of tweaking but should work fine: Print the upper and the bottom part with supports (at least I had to). I used PETG with ~4 shells and ~10% infill (not quite sure anymore). Don't use more infill as this will reduce the trapped air that is needed to float the Trieste up. Removing the supports was a pain was possible eventually. Then glue the two parts together. I printed in PETG and used cyanoacrylate glue (superglue). To help with the gluing process, you can print 2x the alignment bolt and nut to clamp the two parts together. You should print the weights separately and add a layer change in the gcode (this can be a simple colorchange in prusaslicer) or simply pause the print manually when it is at the correct height. Then insert small coins or a led pieces and resume the print. Make sure the metal will not crash with the print head. The last thing you need are the two release hatches. They are fastened with small M3x10mm bolts (or something similar as long as it holds). The release should slide smoothly and not have too much play. If something doesn't work out, I also included the Fusion360 files so you can modify everything as needed. **All aboard!** To start the dive, fill the Trieste with water by submerging it in the bathtub. Then insert the weights and clamp them with the latches. When you are finished with the dive, release the weights and the Trieste will resurface :) Have fun and happy printing!