Summary

With cooler weather, the butter won't just melt on the counter, and I like to leave it out. So I made a covered dish. The hinged lid is convenient. The little triangle thing is to wipe excess butter off the knife.

The dish fits a standard (?) 4 ounce butter cube, roughly 1.5 x 1.5 x 3.25 inches.

Bottom section, 80 minutes, 45g ABS. Top 100 min 50g using Afinia defaults (0.3mm Z, medium speed with a raft).
Metric files included.

ABS is plenty flexible enough to slide the top onto the hinge-pins. I wouldn't know about PLA... probably will be OK.