ELI5: Why are metals smelted into the ingot shape? Would it not be better to just make then into cubes, so they would stack better?

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Whenever you pour something into a mold to solidify, you have to worry about getting it out again, and that’s much easier when the walls are at an angle like \___/. That’s also why molds for cakes or ice cubes are often shaped that way.


It’s to do with the shape of the mould an ease of getting the metal out. Needing the curved sides to release for the mould easier, theres more chance of the metal being stuck in a mould that’s cube shaped. Also, the metal cools better in this shape, cools a lot more evenly resulting in a smaller chance of cracks etc forming.


Twice as long as wide allows for an interlinking stack. All cubes would be unstable. The slight slope to the sides makes it easier to pick up, also pops out of mold easier


Lots of bread pans are a similar shape for a similar reason. They are wider at the top than the bottom, think about why: If they were wider at the bottom then the top if you lifted the bar it couldn’t come out of the mold. If it was the same at the top and bottom the bar would scrape against the edge the entire time you lifted it. So you have to have it be perfectly smooth or pull it hard. if the bottom is smaller, the second you start lifting it upwards it’s no longer touching the sides. So you only need to get it to move a tiny amount then it will fall out on it’s own if you turn it upside down.


When you pack wet sand into a bucket and turn it upside down on your castle, the sand comes out in one piece as the shape of your bucket. If you pack sand into a coffee cup and turn it upside down, likely only the first inch would come out and the rest would be stuck in the bottom of the cup. As others have said, the angle of the walls helps the bar be removed more easily.