Episode 18 of Season 2 is a stream. Last time the wall reached the oil; this time Basket puts it to work. Pumps, refineries and chemical plants go in, and the oil becomes plastic once a coal problem is sorted out. After some cleanup of empty mines, work starts on parts for the rocket. When the stream ends, the parts are only just coming off the line.
Pumps and pipes
Some work happened between streams. A second row of blocks now runs past the forest, "just so my drones don't kill themselves," and a patch of ground has been cleared for oil. The pumps go down first, a lot of them, each turned so a pipe can reach it. The robots do most of the building, which means the pipes can be placed from a distance. "It's really nice having the drones." Once the power lines connect, every pump is running.
Refineries and the oil chain
Next comes a row of refineries, spaced one apart, with water piped underground from up top. The commentary works out the chain out loud: heavy oil gets turned into light oil, and light oil into petroleum gas, each in its own set of chemical plants. "I'm not sure what the good ratio is." Pipes run out partway through, and the robots bring more from the network. One group of plants sits idle until the commentary spots that it never got water. "Now everything has water, everything is happy."
Plastic needs coal
The plastic plants need coal on a belt, so a train drop-off goes in beside them. The first spot is blocked by defenses, so it moves. Then the coal train turns out to be useless. Its pickups are empty: one is "totally dead," another is an old design with missing track. Both stops come out and the equipment is recovered. A viewer's question about trains gets a quick explanation along the way.
The answer is the coal storage block, a cell where spare coal was dumped for a long time. A new pickup goes on its far side, CoalPick0, with stack inserters pulling coal out, and every coal train gets the new stop. It starts slow, so a belt gets looped back and faster inserters go in. The commentary figures there is now enough coal "for the remainder of our playthrough of this season 2."
Plastic, then red chips
"There we go, lots of plastic coming out." More filter stack inserters are added to keep up. Then the plants stop: the copy and paste had missed some pipe connections, so light oil backed up. Once those are fixed, the heavy oil runs faster.
A second plastic pickup station goes in, and Basket rides the train to the red chip area. Red chips are now the slow part. Blue chips come in from the network, and Speed module 2 goes into the crafting queue, to speed up the machines there. "Now we have too much plastic for our actual production."
Research and empty mines
Research has sat empty all stream. Now it starts again with Character logistic slots 5. The commentary wants to research everything before beating the game, for an achievement. Copper looks short too, so Basket rides out to check the copper pickups. Several are empty. Those stops get removed from the schedules and taken apart, along with an iron pickup that "never worked." The commentary calls this "some of the housekeeping I have to do."
Rocket parts
The last stretch is for the rocket. A crafting cell goes down from a template and gets set to Low density structure, which takes steel, copper plate and plastic. Trains for each of the three get the new drop-off added to their schedules. A few missing power poles hold up the build until Basket runs over and places them. The structures come out slowly.
With time running out, one more empty cell becomes a solid fuel maker. It needs no train, only a requester chest, since the commentary counts that "you only need 50."
Where it ends
Character logistic slots 6 is in the research box. "We're almost there, not quite there this episode," the commentary says, expecting to finish next time, and maybe to research the rest off camera. Then the stream ends.