I know this is an ancient thread, but I have a new idea for potential complete automation of piston pumping. Basically using a 3x3 tube of air, only the center column of which is "outdoors" in a freezing biome. Pump pressurized water in, instantly filling the whole thing to the precise level of the first bridges (measured reservoir size, and you would close off the aquifer refill at the same time the valve is opened to the column), ice forms in a column which than collapses down and pistons some magma up, a small amount of which flows off into holding tanks. Then the ice collumn is swallowed by the semi molten rock, along with all the obsidian that results from the draining water. Aquifer refills tank. Repeat, on an automated timer, and those tanks halfway up will be always replenished with magma.
I haven't tested all the parts of this, but I do know that even if the piston gets swallowed by the SMR, the magma it pistons up WILL still flow to the sides before falling, at least some of it. I just did that on a map just now.
The question is more whether the whole ice column will form prior to collapsing or not. Not sure about that.
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