replacing the rudder CA hinges on my giant scale PT 19. They are just old. I was rolling into the shop a couple of weeks ago and the rudder just came off. Glad it happened there instead of in the air. Anyway, I want to put robart hinge pins in place of the CA hinges. They come in different sizes, what diameter of hinge pin should I get for this plane? To be safe I'm going to replace all the control surface hinges with the Robarts.

Thanks