One of my kids has a water bottle with a cap that would be easy to lose, and wanted to make something to keep track of it. So we designed a cap keeper. Amazingly, we had the right colors of filament to make it match!
There’s a loose teal ring printed in ABS, with a tab with a hole in it. It is loose so that it can spin freely on the neck. Then two parts in a bright blue 95A TPU: a band a few mm smaller than the neck that stretches around the neck to hold the ring in place, and a strap that holds the cap. The strap attaches to the cap by being looped through at the end, and to the ring by a nub through a hole (after first looping it through the cap):
Here’s the information on the bottom of the bottle — Simple Modern Ascent 20oz:
(I don’t see exactly this bottle for sale right now; the caps they sell now appear to be the adult sip cup style, which doesn’t need a keeper as much. I also don’t know whether they have the same size neck. But the files aren’t hard to modify.)
FreeCAD (0.22 dev) file and STEP files attached:
Keeper.FCStd (805.0 KB)
Keeper-Band.step (19.1 KB)
Keeper-Strap.step (160.0 KB)
Keeper-Ring.step (69.6 KB)
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