V = Width x Thickness x Length
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 Then we need to know the density of the metal or alloy we’re working with, this is a set value, for example, mild metal has a density of 0.00785 g/mm3, We can then calculate the weight with:
 The conversion factor in this formula talks about the system we’re using to input data, if we’re using inches, we need to convert the density to pounds/in, we can achieve so by multiplying by 36.13
Have in mind that this formula only works in the shape is a sheet.