Exactly right, I dont have much in my collection from the 1700-late 1800s era, but I've looked at several blades in museums and friends collections from that era. 1/8" looked to be the most common thickness, and the bowies from then arent nearly as thick as the ones made today. A Confederate D guard with a 1/4" thick blade would probably weigh 3 pounds or more, the originals were much thinner than that. Most knives that forged this nation were probably simple belt knives with a 5" blade that was close to 1/8" thick, of course what really was the edged tool that did more on the frontier than anything else was a full length axe. I cant think of a old knife I've seen or a military issue knife that would hold up long to the "testing" y'all seem so fond of. I suppose on the frontier they didnt have much need to try to hack through a heavy gage section of sheet metal (not that today we have the need for it either). Of course back then men knew what tool to use for what purpose.