Anvil
Put an ingot on it and strike it with a hammer. Each blow beats it further: bar, then sheet, then plate. One too many and it cracks.
Smithing is how metal becomes parts. Lay an Ingot on the anvil and hit it with a Hammer. Take it off at whichever stage you want:
How many blows
Harder ores take more strikes per stage. A typical common ore goes to bar in 2, sheet in 4 and plate in about 7. The hardest exotics take roughly twice that.
Scrap isn't wasted: a Smelter turns it back into the ingot it came from.