A structural engineer asked me to find the weight of a structural steel frame. I prefer to do calculations with SI units and then convert to necessary units afterwards. I applied a steel material to the assembly and got 393.67 kg for the mass and 0.29 m^3 for the volume. I calculated the density based off of these numbers and I get 1357.5 kg/m^3. The density of steel ranges between 7750 and 8050 kg/m^3. What did I do wrong? I dragged over the cast carbon steel material onto the assembly. I'm needing to get the mass so that I can find the weight of the assembly.