I used to just punch a hole in the bottle cap to make a “self-watering” kind of water reservoir, and i thought the must be a better way.

So i designed this. It screws on every standard glass bottle we have here in Germany and i believe it is the GPI GL25 Thread standard (Glass Packaging Institute).

I prefer Charitea/LEMONAID bottles for their size & aesthetics. Club Mate bottles also work fine and pretty much every other glass bottle with a thread on it.

Just print it in standard 0.2mm settings, no supports, maybe a few more outer perimeters, to make sure it is watertight and only leaks from the 2 small holes. I'd recommend using PETG or ABS, since PLA will degrade overtime or will become leaky.

As of today, 09.03.2024 it is still WIP and i'm still examining if it releases enough or to little water. If i'm not satisfied with it, i'll make sure to update the 3D Models or provide a V2.
I also want to add a thread on the outside to you could “thread” it into the soil.

UPDATE 17.03.2024

I modeled the thread and played around with hole size/quantity. For me, 2x 0.8mm holes work quite well. I've uploaded this V2 and i would't recommend V1 anymore. You can download the .f3d file and adjust hole size/quantity with Fusion 360. You can find two parameters under modify > change parameters tab.

drip_hole_size is gonna be the hole diameter (useful ranges are 0.4mm - 2mm)
extra_thread_tolerance add's some more tolerance to the glass bottle thread (default in the exported models is -0.15mm)

If you need more holes, just modify the quantity in the circular pattern operation near the end of the timeline.


If you want to support my open source work, you can buy me a coffee :)
https://www.buymeacoffee.com/matteohoeren