First please look at this video: https://www.youtube.com/watch?feature=player_detailpage&v=USyoT_Ha_bA#t=200

So idea is to add at least two craftable items: "CAD computer" object which allow player to create a low-poly object in mini-game

and "mold machine" object which can create metal representation of created model.

Game consoles players will not have access to tools for creating mods, and it looks like lore-friendly way to give them a way to create objects of any shape they want.