I woud say the grid is too small, looks kinda flimsy to me. But here are some examples of cages made out of similar, sturdier stuff:
You could probably even use wire mesh found at most home improvement stores. I wouldn't use JUST the mesh - i would layer with wood, as well.
Those are fine for an inside cage. A predator could easily get into that if it was outside and weather would destroy it.
I Guess that would work but remember there for storing books not jumping and peeing Guinea pigs. im sure you have a local shelter or something that has cages
sorry if this answers bad
I wouldn't trust those myself....if anything you should look into C&C cages. They are meant for piggies.
I think those would work for the walls of a cage in place of the metal grids. You can buy Corflute in Australia- same thing as coroplast- for the flooring and low sides.