The Official Handbook of the Marvel Universe: Spider-Man 2005 is out, written by Spiderfan's Al Sjoerdsma and a bunch of his fellow webheads from the site. Al came to me for assistance with some heights and weights because of my extensive training as a clown with the travelling carnivals guessing people's physical attributes. Or perhaps it's my professional engineering license which grants me the right to estimate the earth's gravitational pull on anatomically exaggerated cartoon characters? Whatever the case, because nobody asked, I present for you the calculations that went into the weight estimate for the vibranium skinsuit of the world famous nerd, Charlie Weinerman.
I first had to make some underlying assumptions. We estimated Charlie Weinerman weighing 140 lbs. I found a statistic online that the surface area of skin is somewhere around 1.6 m². I wasn't sure if that would be too high or too low for 5' 7" Charlie, so I just left it. I then assumed the thickness of the skinsuit would be 1 mm (0.001 m). Multiplying the surface area by the thickness produces a volume of 0.0016 m³ of vibranium.
Next, I needed the density of the metal. Steel has a density around 7850 kg/m³. I looked up vibranium and adamantium in the old Official Handbooks of the Marvel Universe. The only clue I could find was that Captain America's shield, a mixture of adamantium and vibranium, weighs 12 lbs and has a 2.5' diameter. I know there's a curvature to the shield, but for simplicity, I assumed it was a disc about 1/20th of an inch thick. That would yield a volume of 0.000578 m³. At 12 lbs (5.44 kg), the density of Cap's shield is 9398 kg/m³. I opted for the density of Cap's shield to approximate pure vibranium. At a density of 9398 kg/m³ for a skinsuit volume of 0.0016m³, the additional weight on Charlie's body is 15.04 kg or 33 lbs. Therefore, Charlie's weight with the skinsuit is 173 lbs! Class dismissed!