[James Sterrett]

You need more starbases. Each one only holds *one* plate or cable component for 10kT of materials each.

You need 100kT of each for a ringworld and 200kT for a Dyson sphere. So you need 10 of each base for a ring, and 20 of each type of base for a sphere. (You only need 1 of the "make it all work" component bases.)