Smelting

Furnaces turn ore and stone into plates, bricks and glass. You build the Brick Furnace from the start; the faster Blast Furnace and the electric Electric Furnace come with research. All three smelt the same recipes.

Furnaces

	Brick Furnace	Blast Furnace	Electric Furnace
Epoch	0	1	4
Unlocked by	Start	Steel Processing	Advanced Smelting
Size	2 × 2	2 × 2	3 × 3
Energy	fuel, 90 kW	fuel, 90 kW	electric, 180 kW
Speed	1	2	2
Rune module slots	–	–	2
Noise	2 per minute	4 per minute	–
Recipe	5 Stone	10 Steel Plate + 10 Brick	10 Steel Plate + 5 Advanced Circuit + 10 Stone Brick

Speed 2 means a recipe takes half the time listed below. See Noise and Unrest and Rune Modules.

No recipe to choose

A furnace has one ingredient slot, one fuel slot and one output. You never pick a recipe: the furnace looks at what lies in its ingredient slot and smelts whatever recipe fits. Put in Iron Ore and you get Iron Plates; put in Stone and you get Stone Bricks.

Because there is only one ingredient slot, a furnace works on one ingredient at a time. A Grabber feeding an empty furnace puts in any smeltable item; after that it only adds more of the same until the slot is empty again. Keep different ores on different furnace lines.

• Press Use to open the furnace window. Click to put fuel and ingredients in and products out, right-click to take items out.
• Crouch and press Use with a stack in your hand to put it in (ingredients into the ingredient slot, fuel into the fuel slot). Crouch and press Use with an empty hand to take all products.

Recipes

Times are for speed 1 (Brick Furnace). The Blast Furnace and the Electric Furnace need half the time.

Product	Ingredients	Time	Locked until
Iron Plate	1 Iron Ore	3.2 s	–
Copper Plate	1 Copper Ore	3.2 s	–
Stone Brick	2 Stone	3.2 s	–
Brick	2 Clay	3.2 s	Masonry
Glass	2 Sand	3.2 s	Masonry
Steel Plate	5 Iron Plate	16 s	Steel Processing
Gold Bar	1 Gold Ore	3.2 s	Golemcraft
Iron Plate	1 Crushed Iron Ore	3.2 s	–
Copper Plate	1 Crushed Copper Ore	3.2 s	–
Gold Bar	1 Crushed Gold Ore	3.2 s	Golemcraft

Recipe locks

Some furnace recipes stay locked until you finish their research. A furnace simply does not accept the ingredient before that: Clay stays out of the furnace until you have researched Masonry, and Iron Plates only turn into Steel Plates after Steel Processing. See Research.

Crushed ore comes from the Stone Golems Refinery, which yields more plates per ore. See Golems.

Fuel

The Brick Furnace and the Blast Furnace burn fuel, and so do the Wooden Drill, the Coal Grabber and the SlaughterHouse. Only these items count as fuel:

Fuel	Energy	Burns in a furnace (90 kW)
Wood	2 MJ	about 22 s
Coal	4 MJ	about 44 s
Tallow	1.5 MJ	about 17 s
Solid Fuel	12 MJ	about 133 s

A furnace only uses energy while it smelts. Leftover energy from a burning item is kept for later. Tallow comes from the SlaughterHouse (Hunting and Farming); Solid Fuel from Oil Processing.

The Electric Furnace takes no fuel. It needs a power pole nearby, see Power.

See also

• Mining
• Grabbers
• Fabricators
• Power
• Research