I drained a mountain!
Well, one level of a magma pipe, anyway.
The dwarves are lifting magma up in prep for an epic Stupid Dwarf Project. I’ve not had much luck with bloody stones or wells, elevators, massive pumps, cradles, wind farms or any of the many other methods described on the boards. Just simple pumps, dwarven powered. After much fumbling personal study, I’ve determined that while NecroRebel’s 1-over-3 powered stacks might be the most efficient means of lift, the Magma Lift Project breaks down if any pump loses prime, collapsing the chain above it and for my guys, in a fortress of about 60 adults, the best we can do is to have about 24 at a time willing to man the pumps. So we bring it up 20 levels at a time, 5x5 (same gain in lag efficiency as the original 3x3 but with extra cushion, doesn’t take that much longer to dig) and then every 20th level is a reservoir with raising bridges that double and then double again the volume, which is more than enough to supply the next 20 z levels toward the surface.
The theory is good, it works, the first 20 levels went off without a hitch. So did the second 20. For the third, it was time to refill that first series and the pump directly over the magma, wouldn’t. ?? It did work, then it didn’t. Turns out, while I’d been watching the pool numbers dance in red between 1’s and 7’s, it wasn’t refilling as expected: that entire top level just evaporated! Very odd, that. To continue the Project, it was necessary to dig down one more level below that first, original pump and have the guys construct another pump station just to bring it up to a reservoir on a level where the stuff used to be. I watched this for nearly two years, waiting for that pool to refill, never did. Still hasn’t.
The Pipe:
This isn’t an elegant solution, in part because there were some valuable gems discovered (couldn’t just leave ‘em there), making for an uneven shape. The raising bridges in lower corridors are just my paranoia from earlier fortresses with flying surprises. It actually isn't a true pipe, either; you can see the candy floor tiles in the upper corner -- this is just the uppermost of three levels above the sea, the part that first opened up on the screen.
A typical pump station and a 20th level pit stop:
Urist’s Cradle can sometimes be constructed by the first 7 dwarves within a year of embark, Wiki says. This stacked system took a dozen dwarves nearly three years to complete and burned a lot of trees for fuel to get that many glass pump parts and grates (107 levels of lift). But now we have magma furnaces and smelters just two levels below the original Metalworks and access to unlimited magma, the only restriction being the near-surface reservoir of 20x20 size. That should be plenty to deal with those damn highly skilled War Elephants that come to visit. I’m thinking, minecart shotgun …
