Colossal Reactors

Build and run large multiblock nuclear reactors to generate power. Feed them fuel and coolant, then extract RF from a power port. Use the Reactor Builder to automate construction, the Melter to turn items into fluids, and Heating Coils to supply heat.

Reactor

A reactor is a hollow box made of reactor casing and reactor glass. Inside you place reactor rods (they hold the fuel) and coolant: either blocks (e.g. diamond blocks, water blocks) or liquids (e.g. water). The better the coolant, the more power and efficiency you get.

Reactor Controller — Place it on the reactor (e.g. on top). Open it to see status, stability, energy output, and to reboot the multiblock.
Rod Controller — Controls how far the rods are inserted. More insertion = more power and heat; you balance this with coolant to avoid overheating.
Resource Port — Insert solid fuel and coolant fluid, and extract nuclear waste and spent coolant.
Power Port — Connect cables here to take out RF.
Redstone Port — Optional. Use it to turn the reactor on or off with redstone, or to require a redstone signal to run.

You need fuel (e.g. uranium-based) and a way to keep the reactor cool. The controller screen shows you if the reactor is valid and how much power it produces.

Reactor Builder

The Reactor Builder automates building the reactor multiblock. You set the size (width, depth, height), choose a rod pattern, and fill its inventory with casing, glass, reactor rods, rod controllers, and optionally coolant blocks or a tank of coolant fluid.

When you start the build, it places the frame, then rod controllers and rods, then coolant (liquid from the tank or blocks from inventory) according to the coolant type you selected in the builder. It will not place blocks where you already have liquid coolant, and it only places the coolant type you chose (e.g. only diamond blocks if you selected that option).

Use it to build colossal reactors quickly and consistently.

Melter

The Melter turns items into fluids (e.g. ingots into molten metal). It has a single item slot and a fluid tank. It does not work alone: it needs a heat source on at least one of its sides (up, down, or the four horizontals). Valid heat sources are lava, campfires, torches, or Heating Coils. Heating Coils give the best heat and are the intended way to run the Melter; lava and campfires work too. More heated sides mean faster melting.

Place the Melter, put heat next to it (e.g. Heating Coils, or lava, or campfires), feed it the right items and it will produce the corresponding fluid. You can pull the fluid out with pipes from the front face.

Heating Coils

Heating Coils are what make the Melter work. They must be placed next to the Melter (any of the six sides). Each coil type “burns” something to produce heat:

Resource Heating Coil — Consumes fluids and/or items from its front face (e.g. water, fuel items). You pipe in what it needs; it heats up and passes heat to the Melter.
Energy Heating Coil — Consumes RF from its front face. Pipe power in; it heats the Melter with no fluids or items.

So you can run the Melter with steam and fuel (resource coil) or with pure power (energy coil). Coils have a simple interface on the front to configure input and, for the resource coil, what to consume.

Summary

Reactor — Multiblock that burns fuel and coolant to make RF; you manage rods and coolant for power and stability.
Reactor Builder — Builds the reactor for you from inventory and tank; you choose size, rod layout, and coolant type.
Melter — Melts items into fluids; needs heat from adjacent lava, campfires, torches, or Heating Coils.
Heating Coils — Supply that heat using either fluids/items (resource coil) or RF (energy coil).