Summary

Several Nautilus submarines from 20,000 Leagues Under the Sea, each painted a different colour.
UPDATE: I've made the tail a bit thicker so you can print at smaller scales.

Instructions

Using Blender I modelled these from an image I found on the Internet.
There are two halves and a stand.

For the Nautilus submarine itself, I usually print each half separately then glue them together.
I scaled the stl by 2000% before printing these samples and I am using PLA with a Replicator 2.
There is a slight amount of warping so you have to hold or clamp the two pieces fairly tight at both ends until the glue sets.
I use super glue (it's the only adhesive I've found that really works with PLA), so you need to align really carefully then commitÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¢ÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂÃÂ¦
Again, I have no alignment tabs of any kind in the models - sorry.
It's easy to paint them after gluing.
Finally, the windows are Wiggle Eyes from any craft store that were painted then glued on.
I could have printed them but you just can't get the finish or resolution that I want on 3D printers (yet).

Oh, make sure you rotate the model so the flat side is on the build plate.
You will need to print the stand twice.

Fleet of Nautilus