Rework of the excellent original from Creative Tools of their Universal Filament Filter.
Originally in FreeCAD, now in OpenSCAD with the filament keeper at 45 degrees.
This helps to accommodate 3mm filaments better.
You will need to fiddle with the filament diameter and "Slot factor" so the filament can be pushed through the slot into its captive hole.
The Round base prints as well with no support as the Flat.(YMMV)
Remember to come back and post what you've printed as Make.
It's good for the designer and the community (that means you)!
To post a Make, come back to this Thing and click Post a Make.
Or, you can use the Thingiverse Mobile app found on
and the Apple App Store.