Pipes, conveyors and shafts

What can I lay between two machines?

Every chest, machine and tank has ports, and you join two ports with a link. There are five kinds: conveyors for items, pipes for liquids and gases, cables for power and signals (power), shafts for rotation and optical fibres for signals. Hold a link and look at a machine: its sockets show up, green for in, orange for out, blue for both, grey if your link does not fit and red if only its size is wrong. A link has no direction of its own: what flows goes from the out socket to the in socket. It all runs in the OVM, even when you are far away.

How do pipes carry liquids and gases?

• A voxel of liquid is 1/64 of a cubic metre, about 15.6 litres.
• Make them at the metal mill: 4 small pipes from one iron or copper sheet; 2 large pipes from 4 steel plates and 2 bolts. Pipes of the older sizes, already laid, keep working.
• One size per socket: a socket takes the size it is made for, and a junction joins sizes (each line flows at its own rate) or splits a line: liquids divide equally.
• Downhill costs nothing: a pipe carries by itself when its arrival socket is lower than its departure and the link is 20 m long at most. Uphill, or farther, it needs a booster pump in line. There is no length limit otherwise, so a pipeline can run for kilometres.
• A valve between two pipes of its size is open or shut by hand (no power) or opened by a signal from 0 to 255 while powered (20 W). A tap on a small pipe fills the empty bucket you hold out to it with any liquid, water or oil.
• Gases never fall into the world: they live in cylinders, in machine tanks and in tanks. A tank holds 16 m³ of one liquid or one gas, never both; the large tank holds more and shows its level. Gases come out of machines under pressure, climb as they descend (20 m), and one line carries one fluid.

How do conveyors move items?

• A glass tube in which you watch the items slide. Lay it from a chest to a machine's input and the machine fills itself; lay it from its output to a chest and the products leave by themselves.
• Craft: conveyors from a hide belt, two iron sheets and a cogwheel; fast conveyors from conveyors, a coil spring and iron sheets. Pieces of the old middle speed keep working.
• A conveyor holds nothing: an item is in a chest or a machine, never two places. Each turn a conveyor passes at most its rate from the node it leaves to the node it reaches; the items you see sliding are only the picture of what passed.
• Same gravity rule as pipes: a tube carries downhill over 20 m at most; otherwise lay a blower (the booster for tubes) in line. To split a line use a junction: items go round robin, each in turn.

How do shafts, gears and pumps work?

• Shafts carry rotation as power: wooden 2 kW, steel 32 kW. Ask more and it slips, everything on it gets its share. A shaft loses 1 % per metre and reaches 32 m between nodes. An electric motor turns it at 120 rpm, up to 2 kW (it draws 2.2 kW).
• Gears come small (1 m across), medium (3 m) and large (5 m), in wood, iron or steel, mounted on a shaft. Two gears with parallel axes, in the same plane, whose distance is the sum of their radii, mesh with no link: the speed changes in the ratio of their sizes, the direction reverses, and each mesh loses 1 % plus 1 % per metre between axes. Output rpm = input rpm x input radius / output radius.
• The pump draws liquid from the ground under it: a 9 x 9 m area around it, down to 32 m, water, oil, lava, milk or kerosene (set the filter on its sheet). It asks 1.5 kW on its shaft and works best at 30 rpm: its efficiency drops by a third at each doubling or halving of the speed, and never goes under 10 %. Straight on a motor (120 rpm) it gives 33 %; a small gear driving a large one (24 rpm) gives 89 %.
• Mind the terrain: the server counts the source voxels in the pump's reach and pumps that amount even in unloaded chunks. The ground drops when those chunks load again.

Updated 2026-10-22