keith hufnagel wrote:
Hello DrPR, being an AutoCAD enthusiast myself, I was wondering if you could show a view which shows the distinctive "tumble home or is it tumble down?" feature of the Cleveland Class ships. Although I am modeling a 1/350 kit I am still a bit curious as to how it should actually look and to exactly it's design function. Thanks!
As originally designed, the Cleveland hull was shaped much like the Brooklyn hull, but with 12-18 more inches of beam to improve stability, and the corners knocked off of the main deck at the stern. When 1.1"/40MM mounts were later specified, it was determined that this extra beam was not enough to keep the design stable without ballast. The lower part of the hull was already in frame, making a simple addition to the beam difficult. But New York Shipbuilding came up with the solution of tilting the armor belt outward rather than inward (the original design had a slight tumblehome - the wider waterline with the slimmer deck promotes stability) but left the deck size unchanged. The idea was workable because construction had not het reached that level. This created a "knuckle" just above the armor belt, and increased the tumblehome above the knuckle. The main deck was not widened because that would have negated much of the stability gained from the revised "tilt". I have referenced a few online photos to illustrate.
The first shot is of Miami.
http://www.navsource.org/archives/04/089/0408917.jpgContrast that with this shot of Helena.
http://www.navsource.org/archives/04/050/0405029.jpgThese shots of Wilkes-Barre show the knuckle both forward and aft of the belt.
http://www.navsource.org/archives/04/103/0410309.jpghttp://www.navsource.org/archives/04/103/0410310.jpgThis shot of Dayton shows the tumblehome above the belt.
http://www.navsource.org/archives/04/105/0410512.jpgThe shot of the Wilkes-Barre's after end shows the tumblehome at the extreme stern created when the corners were essentially knocked off the maindeck at the back of the ship, while the corners at the waterline were left untouched.