Submarine (floating)
thingiverse
I built this model for my son, and it's a compact submarine that stays buoyant in the water! I highly suggest you print one out for your kid or grandkid. You can find more details on how to do it here - http://3d-pechatnik.ru/. If you're looking for something else fun to make, check out this balloon boat: https://www.thingiverse.com/thing:2800577, or try building a steamboat instead: https://www.thingiverse.com/thing:2800309. There's even an upgraded version of this submarine model available online - https://www.thingiverse.com/thing:2780736.
With this file you will be able to print Submarine (floating) with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Submarine (floating).