Toaster from scratch
Here is an interesting project: Thomas Thwaites, who is studying at the Royal College of the Arts in London, has embarked on the quest to build a toaster from scratch, using only raw materials such as iron ore and crude oil.
Though his reasons in no part mention space colonization, his work could have some valuable lessons for those of us wondering what are the minimum necessary equipment, resources and manpower necessary for a group of people to survive and thrive in a colony mostly separate from the mass produced resources available here on earth. Even at this early stage he has learned how to smelt iron ore using only a domestic microwave oven - a handy skill for an off earth colonist.
Some people may disagree with me, but I'm guessing that the first off-earth settlers will be pretty much self sufficient initially. Any supplies delivered on an ongoing basis are likely be limited to lightweight, high value goods, such as roll/fold up solar panels, fuel cell membranes, precision mechanical components, semiconductor devices and medical supplies. Therefore, before they can head out, we will need a clear idea of the infrastructure the settlers will need to maintain their colony at a given minimum mass or value transfer rate from earth.
A lot more work needs to be done in physically building and testing the needed infrastructure for an off-earth colony, and the Toaster Project is a step in the right direction! I would like to see a lot more of this kind of thing, and to get our heads around the problem, I suggest it could be done as a kind of competitive event where several teams compete to see who can reproduce various important technologies from scratch the fastest, based on a set of resources that are themselves reproducible. Possible technologies could range from basic ones such as a smelting facility and forge, glass or glue and fabric, to more complex tech such as a pressure chamber, liquid pump, insulated electrical wire, oxygen/hydrogen production or a functioning mining drill. (I think it would make a great TV show!) Ideally, equipment provided for the competition will also be a goal technology for the competitors, to demonstrate that the colony will be perpetually self sustaining with the given equipment set.
Let me know if this idea or a variant is already in existence.