I have been loving the DC Young Justice cartoon and want to make an Aqualad costume. However i'm having trouble deciding how to build his backpack and the hilts of his water swords. I was wondering if anyone could recommend a material to make the backpack out of that would be sturdy and not too flimsy. So I would appreciate any suggestions about what material I should try to make it out of. Also I'm open to ideas about how to build the hilts as well. I have thought about casting them in rubber but i'm not fully sure if that will work as well. So any thoughts or suggestions are appreciated.