Customizable Self-Starting Siphon

A customizable parametric version of the self-starting siphon that you can tweak to find the optimal size/parameters.

Attached stl file is just an example with a pentagonal tubing.

Suggest printing with 100% infill for water-tightness, and with clear filament. No support required unless you bump up the facet count above 9.

To use, drop it into a glass of water that's filled to the brim (the glass must be deep enough that the inside loop is submerged).

I'm listing dougfeig's design as the source since it's where I got the idea and it contains some useful links for more info, but I wrote this version from scratch in OpenSCAD.

(Updated 9/29/20 to add configurable bend angles and a better example)