The STL is for a 1:20 scale torpedo but can easily be resized in whichever software you use for 3D printing.
I printed the main part of the torpedo in spiralize(vase) mode with adaptive layer height set to range from 0.04mm to 0.2mm in increments of 0.04mm. The propeller was printed with 0.2mm layers and supports.
The author hasn't provided the model origin yet.