Smelting is the process of melting metal. Home smelters are used mainly for melting lead for casting into bullets and fishing sinkers. You can make your own smelter using a hotplate and a heavy pot.
You don't need an expensive hotplate to smelt lead. A cheap model that will get up to the required temperature will do. Lead melts at 327 degrees Celsius. Pick a hotplate that has a wattage of at least 750, so it will get up to temperature quickly.
You need a sturdy pot with a handle that can stand up under high temperatures. Use a pot that's rated for a grill. Cast iron works great. Once you've melted lead in a pot, though, never use that pot for food.
Lead can give off toxic vapours when heated, so always smelt lead outdoors. Never let water come into contact with molten lead, because this will cause the lead to splatter out of the pot.