Thermal Dynamics

Overview

Thermal Dynamics is the transport module of the Thermal Series, adding ducts that carry Redstone Flux (RF) energy, fluids, and items between your machines, tanks, and storage. It is designed to work alongside Thermal Expansion (machines), Thermal Foundation (materials), and CoFH Core, which are all required dependencies. If you've set up Thermal Expansion machines and need a way to connect them, Thermal Dynamics is the answer.

The mod adds five main categories of ducts: Flux Ducts for energy, Fluid Ducts for liquids, Item Ducts for items, Transport Ducts for moving players and entities, and Structural Ducts for cosmetic connections and covers. Each category has multiple tiers with increasing transfer rates and capabilities. On top of that, attachment items like Servos, Filters, Retrievers, and Relays give you fine-grained control over what moves where. You can browse every item and recipe this mod adds using the tabs at the top of this page.

Prerequisites

Thermal Dynamics requires Thermal Foundation and CoFH Core to be installed. Most duct recipes use alloys from Thermal Foundation such as Invar, Electrum, Signalum, Enderium, and Lead. You will need a way to smelt alloys, and some advanced recipes require a Fluid Transposer from Thermal Expansion to fill empty ducts with Destabilized Redstone, Energized Glowstone, or Gelid Cryotheum. If you haven't set up basic Thermal Expansion ore processing and alloy smelting, do that first before diving into the higher-tier ducts.

Flux Ducts (Energy Transport)

Flux Ducts transfer Redstone Flux (RF) between energy sources and machines. They are the simplest duct type to use: place them between a generator and a machine, and power flows automatically with no attachments needed. There are six tiers, each with higher transfer rates and connection capacitance. The base transfer multiplier defaults to 1,000 RF/t and is configurable in the mod's config files.

Understanding Capacitance

Each Flux Duct connection stores a small buffer of energy called its capacitance. This is per connection point, not per duct segment. A Leadstone Flux Duct stores 5,000 RF per connection, so a straight line with two endpoints holds 10,000 RF total in its connections. If you break a duct while it has stored energy, that energy is lost. Higher-tier ducts have proportionally larger capacitance, but the Cryo-Stabilized Flux Duct has zero capacitance because it transfers energy on demand with no internal buffering.

Tier Progression

Leadstone Flux Ducts are your starting point, crafted from Lead Ingots, Redstone, and Glass. From there, you can upgrade through Hardened (Invar), Redstone Energy (Electrum + Destabilized Redstone via Fluid Transposer), Signalum, Resonant (Enderium), and ultimately Cryo-Stabilized (Gelid Cryotheum). The Redstone tier and above require crafting an empty duct shell first, then filling it with Destabilized Redstone in a Fluid Transposer. Alternatively, you can upgrade ducts tier-by-tier using shapeless crafting recipes with nuggets of the next alloy and Redstone Dust.

Fluid Ducts (Liquid Transport)

Fluid Ducts move liquids between tanks, machines, and other fluid handlers. Unlike Flux Ducts, they require a Servo attachment on the source connection to begin extraction. Every Fluid Duct segment stores up to 3,000 mB (3 Buckets) of fluid internally, and throughput varies based on the fluid's viscosity. For standard fluids like Water, the base throughput is approximately 120 mB per tick, but thicker fluids flow slower and Steam flows at a fixed 600 mB/t.

Transparent vs. Opaque

All Fluid Ducts (except Leadstone) come in Transparent and Opaque versions. Transparent ducts let you see the fluid flowing through them, which looks great but requires extra rendering. Opaque ducts use Lead Ingots instead of Glass and are cheaper to craft at higher tiers while also being friendlier to server performance. You can convert between them: combine 6 Transparent ducts with a Lead Ingot to get 6 Opaque ducts, or combine 6 Opaque ducts with Hardened Glass to get 6 Transparent ones.

Temperature Restrictions

Leadstone (basic Copper) Fluid Ducts only handle moderate-temperature fluids. If you pipe Lava, Gelid Cryotheum, or other extreme-temperature fluids through them, the duct will break and spill the contents. The temperature safety range is 250K to 800K. Hardened Fluid Ducts and all higher tiers handle any temperature safely.

Signalum-Plated Fluid Ducts

The Signalum-Plated Fluid Duct is a hybrid that transfers both fluids and RF energy at up to 4,000 RF/t through the same pipe. Craft it by combining a Hardened Fluid Duct with Signalum and Electrum Nuggets. This is one of the most useful ducts in the mod because it eliminates the need for separate fluid and energy lines running to the same machine.

Super-Laminar Fluid Ducts

The top-tier Super-Laminar Fluid Duct has no throughput limit when pressurized. If the pipe system is completely full of fluid with no air gaps, it transfers fluid instantly regardless of pipe length. If the supply can't keep the pipe full, it falls back to normal throughput. The Super-Laminar duct does not connect with other Fluid Duct types, so your entire run must use Super-Laminar ducts. It is crafted in a 3x3 pattern using Bronze Ingots, Hardened Glass, and a Hardened Fluid Duct in the center.

Item Ducts (Item Transport)

Item Ducts are the item transport backbone. Unlike energy cables, items need something pushing them into or pulling them out of the duct network. A Servo on a source inventory pushes items out, while a Retriever on a destination pulls items in. Machines from Thermal Expansion can also push directly into Item Ducts when their output sides are configured.

Standard vs. Impulse

There are two speed tiers of Item Ducts. Standard Item Ducts (crafted with Tin and Hardened Glass) move items at normal speed. Impulse Item Ducts are the fast version, created by filling a standard Item Duct with Energized Glowstone in a Fluid Transposer. Items visibly move faster through Impulse ducts, making them ideal for high-throughput automation lines. Both types come in Transparent and Opaque variants.

Signalum-Plated Item Ducts

Like their Fluid Duct counterparts, Signalum-Plated Item Ducts transfer both items and RF energy (up to 4,000 RF/t with 40,000 RF capacitance) through the same pipe. This is particularly useful when running pipes to machines that need both power and item input. The Signalum-Plated Impulse variant combines the speed boost with dual functionality.

Dense and Vacuum Variants

Any Item Duct can be converted into a Dense or Vacuum variant using shapeless crafting. Dense Item Ducts (add 3 Lead Nuggets) have a path weight of +1,000, meaning items strongly prefer to travel through them. Vacuum Item Ducts (add 3 Silver Nuggets) have a path weight of -1,000, meaning items avoid them. This lets you build priority routing without complex Redstone logic. For example, items will take a longer Dense path over a shorter Vacuum path, letting you create overflow systems where a primary destination fills first.

Attachments: Servos, Filters, and Retrievers

Attachments are items that snap onto duct connection points to control the flow of items and fluids. They are the control logic of your duct network. There are four types: Servos, Filters, Retrievers, and Relays. Each comes in five tiers (Basic, Hardened, Reinforced, Signalum, and Resonant) with increasing capabilities.

Servos

Servos are the most fundamental attachment. They extract items or fluids from the inventory they're attached to and push them into the duct network. Right-click a Servo to open its configuration GUI where you can set whitelist/blacklist filters, Redstone control mode, and stack size limits. A basic Servo is crafted from Iron Ingots, Iron Nuggets, Glass, and Redstone Dust.

Filters

Filters attach to destination connections and control what can enter that inventory. They don't extract anything on their own. Use a Filter when you want specific items going to specific chests or machines. A basic Filter is crafted with Iron Ingots, Iron Nuggets, Glass, and a Paper (Items.field_151121_aF in the recipe code). Higher tiers unlock more filter slots: Basic gets 3 slots, Hardened gets 6, Reinforced gets 9, Signalum gets 12, and Resonant gets 15 filter slots.

Retrievers

Retrievers are the opposite of Servos. Instead of pushing items from a source, a Retriever pulls specific items from anywhere in the connected duct network into the inventory it's attached to. This is powerful for "on-demand" systems where a machine needs a specific input. Retrievers are crafted with Iron Ingots, Iron Nuggets, Glass, and an Ender Pearl. They support the same tier upgrades as Servos and Filters.

Attachment Upgrades and Crafting

All three attachment types (Servos, Filters, Retrievers) follow the same tier-upgrade pattern. You can either craft them directly at any tier or upgrade an existing lower-tier attachment. To craft directly, use the shaped recipe with the tier's corresponding Ingot (Iron for Basic, Invar for Hardened, Electrum for Reinforced, Signalum for Signalum, Enderium for Resonant), along with Iron Nuggets, Glass, and Redstone Dust (for Servos) or Paper (for Filters) or an Ender Pearl (for Retrievers). Shapeless upgrading works by combining any lower-tier attachment with the target tier's Ingot, skipping intermediate tiers entirely.

Filter Options by Tier

Higher-tier Filters unlock more filtering options. All tiers support whitelist/blacklist toggling. Starting at Hardened, you gain access to metadata matching, NBT matching, Ore Dictionary matching, and mod-based sorting. The filter grid width also increases: Basic gives you a 3x1 grid (3 slots), while Resonant gives a 5x3 grid (15 slots). Higher tiers also unlock stock-keeping mode, route type selection, and anti-spam filtering for precise logistics control.

Relays (Redstone Over Ducts)

Relays are a unique attachment that transmits Redstone signals through the duct network itself. They come in three modes: Input (reads a Redstone signal from adjacent blocks), Output (emits a Redstone signal), and Comparator Input (reads a comparator signal from adjacent inventories). Relays support 16 color channels, so you can run multiple independent Redstone signals through the same duct line without interference.

Each Relay can be configured with signal inversion and threshold logic. When threshold mode is enabled, the Relay outputs a full-strength signal (15) when the input meets or exceeds the threshold, and zero otherwise, acting like a digital switch. Relays are crafted from Signalum Nuggets, Lead Ingots, Nether Quartz, and Redstone Dust. They work on any duct type, including Structural Ducts, making them a way to run Redstone signals through decorative builds.

Structural Ducts and Covers

Structural Ducts are inexpensive non-functional ducts crafted from Iron Nuggets and Lead Ingots (6 per craft). They don't transfer anything on their own but serve two important purposes. First, they connect to all other duct types and can carry Relay signals, so they act as a cheap backbone for Redstone distribution. Second, and more importantly, they are the base ingredient for Covers.

Covers are cosmetic facades that snap onto any duct face. To create them, combine a Structural Duct with any solid block in a crafting grid to produce 6 Covers with that block's appearance. Place a Cover on a duct face by right-clicking, and remove it with a Crescent Hammer (from Thermal Foundation). Covers respect the block's directional textures, so a Grass Block Cover shows Grass on the top and Dirt on the sides, exactly as you'd expect. Covers also make the duct face solid, allowing you to place blocks against them.

Transport Ducts (Entity Transport)

Transport Ducts are large-bore ducts that move players and other entities. They are visually much larger than standard ducts and allow players to enter the duct network and travel rapidly between connected points. There are three types:

The Transport Duct (standard) is crafted by filling a Transport Frame with Aerotheum in a Fluid Transposer. The frame itself is made from Bronze Ingots and Hardened Glass. These ducts accelerate entities along the network and can be configured with a wrench to set direction preferences. The Long Range Transport Duct is crafted from Lead Ingots and Hardened Glass and is designed for extended-distance travel. The Linking Transport Duct (also called Warp) is created by filling a standard Transport Duct with Resonant Ender in a Fluid Transposer, and it enables cross-dimensional or long-range teleportation between linked endpoints.

Right-clicking a Transport Duct with a Crescent Hammer opens a configuration GUI where you can name the endpoint and set a display icon item. This name appears when players approach the endpoint, making it easy to build labeled transit systems in your base.

Key Materials and How to Get Them

Thermal Dynamics relies heavily on alloys and special fluids from Thermal Foundation. Here's a quick reference for the materials you'll need most:

Lead is used in basic Flux Ducts, Opaque duct variants, and Structural Ducts. Lead Ore generates in the world and is smelted directly. Copper is used for basic Fluid Ducts. Tin is used for Item Ducts. Invar (Iron + Nickel alloy) is used in Hardened-tier ducts and attachments. Electrum (Gold + Silver alloy) is used in Reinforced-tier items and empty Flux Duct shells. Signalum (Copper + Silver + Redstone alloy) is used for Signalum-tier ducts and plated variants. Enderium (Tin + Silver + Ender Pearl alloy) is used for Resonant-tier items. Bronze (Copper + Tin alloy) is used for Transport Duct Frames and Super-Laminar Fluid Ducts.

Configuration

Thermal Dynamics provides several configuration options. Client-side settings are in thermal-client.toml in the config folder, while server-side settings are in thermal-server.toml in the world's serverconfig folder. The most important configurable value is the base energy transfer multiplier (default 1,000 RF/t), which scales all Flux Duct transfer rates. You can also toggle whether Cover recipes are enabled and whether advanced duct recipes use the Fluid Transposer (if Thermal Expansion is installed) or fall back to shapeless crafting alternatives. If you're running on a server, copy your thermal-server.toml to the defaultconfig folder so it applies to all new worlds.