We have some information regarding ship building from Michael Wagner (Star Atlas CEO). The time requirement will differ depending on the size of the ship/item. Mega projects will likely take quite a long time by default, but can potentially be sped up through additional contributions. He also added that “All resources will be required, though we might break it out so that segments of a ship can be built and combined over time“. In addition to that, large ships could take weeks/months to build. However, this is still being worked on.