I had trouble with some straight fit test tube holders so I found this one and had no issues. I printed at 20% infill with snug supports. Prints in one piece!
Remixed to use less filament. Also created a horizontal version if you have a bigger printer but I need to clean up the mesh.
To hang, use twine or thin nautical rope and knot securely in the holes with enough space in between. Knot at even points so it doesn't skew off center. I used glass jars with herbs so all I needed was a thumbtack. This way it also easily converts to tabletop use for when you're cooking (or baking or making your tea etc).
The author remixed this model.