Materials
In Feedback, what something is made of matters more than what item it is. Machines, magnets and guns don't check for "an iron ingot". They look at the material: how hard it is, how dense, whether it's magnetic, how strong. Any item made of that material behaves the same way.
The metals
| Metal | Hardness | Density | Strength | Melts at | Notes |
|---|---|---|---|---|---|
| Lead | 0.3 | 11.3 | 0.5 | 327 Tu | Dense: the classic bullet metal. Useless for guns. |
| Silver | 0.9 | 10.5 | 3 | 962 Tu | Soft and bright; the best conductor. Its smite hurts the undead. |
| Gold | 0.5 | 19.3 | 2 | 950 Tu | |
| Tin | 0.6 | 7.3 | 1 | 232 Tu | For bronze. |
| Copper | 1 | 9.0 | 4 | 1000 Tu | The first metal you'll work. Wire, cable, plates, foil. |
| Zinc | 2 | 7.1 | 3 | 420 Tu | For brass and the Galvanic Cell. |
| Brass | 4 | 8.5 | 5 | 900 Tu | 65% copper, 35% zinc. Good cartridge cases. |
| Bronze | 5 | 8.8 | 6 | 950 Tu | 90% copper, 10% tin. |
| Wrought Iron | 6 | 7.9 | 8 | 1600 Tu | Magnetic. Vanilla's iron: soft, tough, worked cold. |
| Cast Iron | 12 | 7.2 | 6 | 1200 Tu | Magnetic. Too brittle for plates, rods or wire; good for steelmaking. |
| Steel | 15 | 7.9 | 15 | 1450 Tu | Magnetic. Only moves between 900 and 1100 Tu. See Making Steel. |
| Hardened Steel | 25 | 7.9 | 35 | 1450 Tu | Magnetic. Only the Grinding Wheel can shape it. |
| Tempered Steel | 20 | 7.9 | 28 | 1450 Tu | Magnetic. Tempered hardened steel: tough again. Worked cold, never hot. Springs, blades, gun parts. |
| Netherite | 40 | 13.5 | 50 | 2600 Tu | Magnetic. Harder than every cutting tool. |
What the columns mean in play:
- Hardness decides what can shape a metal. A blow weaker than the hardness, or a cutting tool not harder than the metal, does nothing at all. Above that, each blow does strength of the blow ÷ hardness in work. See Metalworking. It also decides what a bullet goes through: see Guns.
- Density (kg per litre, water is 1) decides how heavy things are: bullets, guns, engines and vehicle plates. Dense bullets keep their energy.
- Strength decides how much pressure a gun chamber or a cartridge case holds, and how fast an engine can rev. A 9 mm chamber with a 3 mm wall holds 1.33 × strength in Pu. See Gun Parts.
- Melting point is where a crucible melts it, and where a Fuse wire or a pair of tongs gives out.
- Magnetic metals are pulled by the Electromagnet and work as coilgun slugs.
Electrical figures (how much current a wire of each metal carries, its voltage loss, and its electrode potential) are on the Fuse and Electrolytic Cell pages.
Other materials
Not everything is metal. A few others matter for parts and protection:
| Material | Hardness | Grip friction | Stands | Used for |
|---|---|---|---|---|
| Wood | 0.5 | 0.4 | 150 Tu | grips turned from a stick |
| Bamboo | 1 | 0.4 | 150 Tu | grips turned from a stalk |
| Bone | 3 | 0.5 | 200 Tu | grips turned from a bone |
| Leather | 0.3 | 0.6 | 100 Tu | gloves; wrapping a grip |
| Wool, Paper | 0.5 | wrapping a grip | ||
| Honey | 1.5 | wrapping a grip: the grippiest there is | ||
| Diamond | 100 | armour: nothing pierces it | ||
| Heavy Core | 9 | found, not made: see Heavy Core | ||
| Graphite | coal baked at 2200 to 2600 Tu; no use yet |
Every material also decides how well it takes an enchantment when it's the main part of a tool or piece of armour: gold is best, then leather, wood, iron and netherite, with stone worst.
"Stands" is the temperature a grip or glove can bear against your hand. See Hazards.
Forms
Every metal comes in a family of forms, each made by a particular machine:
| Form | Made by |
|---|---|
| Ingot, Nugget, Block | crafting (nine nuggets ↔ ingot ↔ block) |
| Plate | hammering an ingot |
| Foil | hammering a plate (keep going) |
| Scrap | hammering foil (too far) |
| Rod | Rolling Mill |
| Wire, Fine Wire | Wire Drawer |
| Case | drawing a plate |
| Bullet | hammering a nugget, or casting |
| Drilled Plate | Drill Press |
| Turned Rod | Lathe |
| Ground Ingot | Grinding Wheel |
| Swarf | the leftovers of drilling, turning and grinding |
| Gun Barrel, Receiver, Slide, Bolt, Trigger Group, Grip, Cylinder, Magazine Tube, Suppressor, Muzzle Brake, Relief Vent, Barrel Shroud | machined: see Gun Parts |
So there's a Bronze Plate, Lead Wire, Gold Foil and so on, for every metal. A few don't exist: cast iron is too brittle to be made into plates, rods or wire, and neither is hardened steel. Tempered steel is: plate, rod, wire and the machined parts, but no foil, nuggets or blocks.
How much work each step takes depends on the metal: a fixed amount plus a little more for every point of hardness. A copper plate takes 14 Fu; a steel plate 60. JEI shows the figure for every step and every metal.
Where to find them
Copper, iron and gold come from vanilla ores. Brass and bronze are alloyed. Steel and cast iron are made in a crucible. Pure copper can also be refined out of brass or scrap in the Electrolytic Cell.
Tin, zinc and lead are ores in the ground. Silver has no ore of its own: heat galena hot enough and a little silver comes out of it. Silver comes as ingots, nuggets and blocks.
Some materials also carry a perk: what they do to whatever a weapon made of them hits.