Angle Iron, or L bar-shaped iron, is commonly used in types of construction work. Because the shape of angle iron is very basic and geometric, it's possible to calculate the weight of angle iron knowing only its dimensions and the density of cast iron.

Take the dimensions of the base of the angle iron. For this tutorial, the base will be defined as the "foot" of the "L." You'll need the width, length and height. Assume the width is the shorter side and the height will be measured as the vertical height if the "L" is oriented properly.

Calculate the weight of this segment. This is given by width times length times height times the density of iron, which is 0.259 lbs. per inch cubed.

Take the dimensions of the tall portion of the "L." Calculate the weight by multiplying the width times the length times the height and then multiplying the resulting volume by 0.259.

Add these two weights to get the total weight of the angle iron. If you counted the corner intersection of the long and short parts of the "L" twice, you'll need to find its weight and subtract that from your final result.