[@Zelosse]He's not sure if he does want to speak( still confused about the idea if wanting in general), and if he does do so it'll take more than just metal, it'll take a bit of wiring, magic circuitry, and other bits and baubles to make it function as needed, not to mention the time nerfed for him to come up with a compatible design. If you gave Risty metal right now, he'd deconstruct it, then just stare at you in silence as he waits for something else to happen. 

He'll either be talking, or finding some other method of communication, probably after the 2 year time skip scheduled after the games, or whenever it feels right.