I looked at lots of different funnels trying to find one that fits a common paper resin-filter. To be fair, there are a few good ones out there. But the good ones seem overly complex.

I do like the ventilation idea. And I like the flutes ("innies") better than the fins ("outies").

This project started as a set of SCAD parameters for Luu Lac's Smart Funnel (https://www.printables.com/model/42702). However, the code had some geometry issues, and the resulting model was broken.

This is a near total rewrite, which seems to be better behaved for a wide variety of parameters.

The default parameters will make a funnel with flutes that fits common paper resin filters. The .stl and .bgcode files were generated using the default parameters.

But my primary objective is to post what I believe is a working SCAD script which creates simple fluted funnels.