To always know how much beer is left in my kegs, I followed these instructions:
https://www.instructables.com/Beer-Keg-Scales/
Some .stl files are provided to construct the scale main bodies from wood in the link above. However, I changed the design to fit on a Prusa Mk3S+, so it can be 3D printed. Despite the cut away segments of the originally circular scales, the corny kegs fit nicely.
I printed in PETG with 100% infill to get maximum stability. Probably a lower infill would still work, but I haven't tried it.
The author remixed this model.