Sandustry Wiki

Slag Burner Guide

There is no official building named “Slag Burner” in Sandustry. Players use the term for any setup that turns Residue into Burnt Residue, the intermediate material that feeds the Kinetic Press. This guide covers every reliable method, from manual ignition to full automation.

Why Burn Residue?

Residue is the slushy by-product of sifting Wet Sand in a Shaker. Burning it is the middle step of the core Gold chain:

Wet Sand → Shaker → Gold + Residue → burn → Burnt Residue → Kinetic Press → 1 Gold + 1 Seed

Key facts from the official wiki:

  • Residue has a density of 50 and is burnable.
  • When Residue touches Fire, each pixel has a 25% chance to become Burnt Residue; otherwise it burns away.
  • Fire spreads through touching Residue pixels.
  • Burnt Residue must fall at least 25 blocks through a Kinetic Press to output Gold and Seeds.

Method 1 — Manual Burning

The cheapest method requires only early-game tools:

  • Flamethrower (Tier 2, 400 Gold): aim at a Residue pile and ignite it. Fire spreads through the pile on its own.
  • Rocket Launcher with the napalm upgrade can also start fires.

With a steady Residue feed, a single ignition can keep burning continuously. Feed the pile rather than burning batch by batch.

Method 2 — Lava Trap

Before unlocking dedicated machines, you can automate burning with Lava:

  1. Trap Lava in place using a Filter (Tier 1, 250 Gold) set to let Residue through but hold the Lava.
  2. Run the Residue stream over or through the trapped Lava on a conveyor line.
  3. Collect the surviving Burnt Residue at the end.

For details on moving Lava, see the Beginner’s Guide: freeze it into Cinder, move it, then reignite it.

Method 3 — Burner Belt + Thermal Buffer

This is the official automated setup, unlocked at Tier 2:

ComponentResearch CostRole
Burner Belt500 GoldIgnites flammable materials passing over it when heated.
Thermal Buffer1,000 GoldStores and distributes heat to nearby machines.

Setup steps:

  1. Place a Thermal Buffer next to the Burner Belt and supply it with heat.
  2. Route Residue across the Burner Belt on its way from the Shaker.
  3. Surviving pixels fall off as Burnt Residue; drop them 25+ blocks through a Kinetic Press.

Method 4 — Pyro Dispenser

ComponentResearch CostRole
Pyro Dispenser2,000 Gold (Tier 3)Fires a flame burst every 3 seconds when fueled by an adjacent Thermal Buffer.

Point the Pyro Dispenser at the Residue pile or belt section. It re-ignites automatically on a fixed cycle, making it a hands-free way to keep a burn pile alive.

Troubleshooting

ProblemCauseFix
Residue vanishes, little Burnt ResidueExpected — only 25% convertsIncrease Residue throughput; you cannot “burn hotter.”
Burn pile goes outIntermittent inputKeep a steady Residue feed; add a Pyro Dispenser.
Kinetic Press outputs nothingDrop height too lowBurnt Residue must fall at least 25 blocks through the press.
Need Seeds as well as Gold—The press always outputs both; route Seeds to Planter Boxes.

Sources

This guide is a rewritten compilation based on:

Related Pages