8. 40 The first things to be moved to the colony location are the living quarters. Each unit is built to fit inside the Shuttle cargo bay, and can be delivered complete and operable. Next, the mast and an early small power station are deployed, the pieces of the work shacks are deployed and assembled, and the shacks are attached to the mast. The heavy and light machine tools are brought up in pieces and installed in the work shacks (see Figure 8.12). The remainder of the complete 60 MW power plant is then deployed and set up. The next step depends on the relative readiness of the lunar base facilities and transportation network which brings the raw material from the Moon. If this network is operating, the transportation of lunar raw material is begun and the cranes and frame are built using the industrial capability of the work shacks. If the lunar supply network is not ready, the material for the cranes and frame are brought from Earth. Once the cranes and frame are assembled--two to three years after the first human reached the colony location--the colony construction site is finished and ready to begin the receipt of lunar raw material and the construction of the colony. VIII.7.3 Colony Assembly Process VIII.7.3.1: Assembly Tolerances and Choice of Technique: This section explains the rationale behind the subassembly technique used for colony construction. As described in Section VII.3.4, the building block for the colony is the lm x lm steel plate. Such plates, separated by crack-stopping stiffeners, form the hull and bulkheads. The most straightforward construction scenario would involve assembling the entire colony directly from such plates and stiffeners. This would require transporting and positioning nearly 2 million pieces (plates, minor stiffeners, and major stiffeners) so that they could be joined together. Section VIII.5.2 explained the desirability of EB welding as a joining technique due mainly to its high speed, versatility, and low cost. However, the EB welding process also requires close alignment of the surfaces to be welded. The difficulties in achieving this alignment for close to 2 million pieces and the complication and expense of alternative joining
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