Solenoid valve SG90 servo conversion

Convert the cheap, ubiquitous solenoid valve to servo-actuation so your arduino plant waterer doesn't need its own power station.
This mod means you only need power to move the servo arm, not the whole time you want water flowing. So you can make a plant watering system without all the batteries in the world and do everything with 5 V.

Requires:
SG90 servo
10mm disc magnet
Polypropylene solenoid valves
Microswitch for position feedback (optional)

Carefully bust off the solenoid part then slot this together and pop it on top.

Update: Now controls 2 valves. The main block has breakaway support built into the model. Split and remove that if it's not your thing.
There's a bit of wiggle room to get the servo lined up just right, so don't push it all the way in and screw it down tight right away.