PET bottle irrigation spike

The cap is designed to fit PET bottles (with thread PCO1881 which fit all bottles I could find in my household) and turn the bottle into a water irrigation system for e.g.  flowers.

The cap is printed without support, but a 0,2 mm surface is to be cut out from the bottom, refer to the pictures.

Make sure the soil is wet before the bottle is installed, otherwise the bottle will drain faster.
Fill a bottle with water, screw the cap on the bottle and place it upside down in e.g. a flower pot. Now the plant can be left for a few days.

The tip can be cut if a larger hole is needed.

2022-06-08: MkII added with improved profile to allow better support in the pot. Also added four rows of holes on the wall. 
Hole dimension decreased on first version.

2022-08-05: Added different versions of MkII with alternative hole sizes.
There are now versions with 1 mm, 0,75 mmm and 0,5 mm sized holes. It seems different type of soil requires different hole dimension not to be emptied too quickly.

2022-08-16: Added 0,5 mm single (top) hole only version.