Under watering tray with bottle, 16 cm

UPDATE 28.6.2021

After using this for some days, I can say that it is very difficult if not impossible to use without watering the general area around the tray when turning the tray around with the bottle. The tray is also impossible to move with the pot without making a mess, so I will design a new tray which will address these issues. I will leave this post as is.

Original

You can attach a regular 1.5 liter cola bottle to this bottom/under watering tray to keep the plant watered. The bottle will keep the water level at about half the height of the tray edge, at 1-1.5 cm. The diameter of the tray is around 16 cm and the angle of the edge is 60 degrees, so any pot within these limits fits. I haven't devised a method to attach the bottle when the tray is right side up, but might come back to it later.

The design is not super stable, you can easily knock the bottle over if you nudge it too much. It will not however fall over on its own.

I live in Finland and have designed the thread with bottles sold here. The thread is not perfect, its quite stiff if not impossible to screw fully in, but its not required. The bottle won't leak once the water level rises to the lips of the bottle, the thread or the amount screwed does not affect that other than raising the bottle.

The gcode has the tray in two parts because it does not fit M3KS+ in one piece. I used a solder iron to join them, as I do not know a good glue for PETG. In the image there is some strings sticking out, because I haven't cleaned it with sanding.

I might upload the thread model separately, so you can attach bottle threads to your own designs.