Specific gravity of steel is 7.8 times that of water Water weighs 1000 Kg/m3 Therefore (depending on the grade) acubic meter of steel would weigh 7800 kg
As a guide it is easy to compare weight and cubic metres of water and so; 1 cubic meter of water weighs one metric ton ( 1000kg). The density of wood can vary so much eg balsa is so light perhaps 150kg per cubic metre and ebony perhaps 2000kg. The only real answer is that you need to know what sort of wood and then work out with a small test (displacement) what the mass is. If you sink the wood in to water and collect the water you can work out the mass, weigh the wood and you have the answers.... simples