The smeltery is created using a smeltery controller, a seared tank, and a number of seared bricks. Drains can also be added to any place on the smeltery. To drain you need to attach a faucet to a smeltery drain block.
Alloys are created automatically when you insert the right combination of materials.
Aluminum + Copper = Aluminum Brass
Aluminum + Iron + Obsidian = Alumite
Colbalt + Ardite = Manyullyn
Copper + Tin = Bronze
Gold + Silver = Electrum
Iron + Nickel (Ferrous) = Invar