This design represents a dental floss holder that fixes the main problem of almost all floss holders - tensioning! Floss tends to stretch almost immediately, causing handling problems.
My design uses a movable part that serves the function of both holding the floss in place and providing a way to tighten it. Look at the pictures and you will understand how to use it. I use mine daily and it really works exceptionally well for me. Of course, your mileage may vary.... ;-)
I recommend printing in PETG for higher elasticity, 0.15 mm layer height, 40% infill without supports. PLA also works well, but can be a bit more brittle in the long run.
This is a print-in-place design - after printing just wiggle it a bit to release the moving part.
Note: The design is widely tested for nozzle sizes of 0.4 mm or smaller on different printers. For bigger nozzle sizes (e.g. 0.6 mm) I have added a STL file using bigger tolerances for the tightening sled (0.35 mm instead of 0.2 mm) in the file “DentalFlossHolder_0.35-spacing.stl”. Just load it in the provided PETG or PLA Prusa Slicer files, replace the main object and slice it with the given settings.
Required parts:
Here is a tech drawing:

Change history:
The author marked this model as their own original creation.