I modeled this springo after my popular Chromatic Vase. It has the same distinct ridges... but it's a springo!
Two sizes. I got the best results printing with 3 outlines/shells, 0.15mm layer height, and enough solid top & bottom layers to make the spring part solid infill. No supports required.
After printing, carefully separate the coil using a thin spatula, palette knife, butter knife, etc. Work slowly and with caution, especially if you are using sharp tools!
Springos pictured were printed using MatterHackers PRO PLA on the KR-10S dual color 3D printer.