“Hey, which do you think is heavier, the Katana Buddha or Soto the Twin? I know that the Katana Buddha was made from like a hundred thousand swords, but the Twin has gotta be heavier than that. To be honest, I’m kind of worried that Konayuki’s ship might sink before she makes it to Owari.”
“No need to worry. She’s on a man-of-war, the pride of the Owari Bakufu. The Old Shogun never saw a ship the likes of this. It’s practically unsinkable.

Katanagatari Omnibus 2, Page 293