Well you have to go at a certain time, I think it was 6 to 10 pm, he is busy doing something, I forget what....but he is out! And let me tell you...when he is out and when you get the blueprints (I beat the game a while ago), you have to go on the sundeck, and then you have to defeat that robot and his clones or whatever! Good luck!
He's recharging. And don't forget you have to beat him 3-4 times. So don'y get discouraged!