The Rio Grande Class Cruiser is laid down in 1927, and will be launched in 1930. I'm going to take my time on this ship, and share how I've learned to put them together from the first pixel to the last. The Rio Grande is the 30th ship I've drawn for the Republic of Texas Navy, and I'm still refining how I do it.
This is what I used to call a base layer, but it is the first layer in the pdn file. The page is divided into three parts: at the top is the part that will become the inboard profile. The middle part is for body plan sections to help me shade the hull (I'm trying a new technique since I'm not completely satisfied with how I shade hulls). The bottom part has the beam and length lines to help me lay out the deck plans.
The top section has the hull dimensions laid out. The bottom box becomes the hull below the waterline, the top boxes define the slope of the main deck and the freeboard. The midships reference line is obvious, and the lines just to the left and right define the limits of the vital space...no guns or machinery past those points. Dimensionally, that data comes right off Springsharp.
My next step and next post will have the hull form refined and the decks laid out for the inboard profile.