I made this to clean up the appearance of a hole I needed to drill into the top of my printer enclosure to run filament from above. It is sized for 1.75mm filament, and just sticks out on the bottom of the .75" MDF I used for the top of my enclosure.

This fits well into a hole drilled with a .25" drill bit, and a bit of super glue applied to the underside of the lip has held it in place perfectly well.

You can tweak the dimensions in OnShape, if need be.