Looking for a (very) simple funnel? My wife needed a very simple (and pretty small) funnel to fill some nail polish bottles (10ml / 0.3oz). The funnels we had were too big so I designed a very simple one in Fusion360.

I asume it should be scalable to the size you need. Just print it with no bottom and top layer and no infill. I used 2 walls since it is a small print, if you go bigger I suggest you go with 3 or 4 walls.