Double Bottom! (Patreon)

With enough plating blocked out, I decided to start work on the double bottom structure. I started with the center keelson which ranges in height from 5' 3" to 6' 3" under the engines with some variation at the bow and stern. This center keels connects to the keel plates and bars and tank top plating.

Attached to the center keelson are the tank frames. These are what the bottom plating is riveted to and they have some variation fore and aft. There will also be intercostals running throughout. The structure of the double bottom isn't 100% clear everywhere but it's fairly simple to figure out and extrapolate from the iron plans and photos we do have.

I still have a few details to add to the bottom frames - what you see here is a preview - but there are a few things you can see in the images now, like the butt straps for the keel plates, the various angle bars for connecting the keelson to the keel, the frames to the keelson, and the plating to the frames, as well as the plate overlaps of the center keelson plates. Note the way the overlaps are cut or "scarphed" to make way for the angle bars top and bottom.