[Robotgroup] Cool water printer

[TomD]

The trick is, finding valves that don't distort the water flow when they change state.
you need something that has a very smooth flow when on, or you won't get the nice water columns.
Putting a long pipe after the valve is going make for ragged turn off and drips.

They may have a large manifold just above the valves that is a room pressure, so the flow is gravity
feed only.