A prominent feature of most pre-WWII capital ships was the large cowl vents used for ventilation. Although smaller sizes continued to be used, the large "man sized" ones used for primary ventilation gradually disappeared, especially as battleships and such went through rebuilding in the 1930's
While the few ship plans of battleships from the pre-WWI period show the deck openings, it is hard to know the size of the main opening as these vents had a graduated diameter.
Does anyone know of a reference that lists the various sizes on US ships and, especially helpful, are there vendors how sell these in standard sizes, i.e. 1/350
While not impossible to make - the dimensions are critical to get them to look "right"
Thanks

Saransk,

One possible source of information is the Philadelphia Seaport. In their collection they hold plans and images of many of the ships built by William Cramp & Sons Shipbuilding. As you may know, Cramps was a premier shipbuilder of the era and constructed a number of ACR, protected cruisers, armored cruisers, and predreadnoughts, for both the USN and some foreign navies (Protected cruiser Kasagi for Japan, protected cruiser Varyag and predreadnought Retvisan for Imperial Russia). Since they have breadth and depth to their collection, you can get a feel for the cowl size for a particular type.

Kip

https://www.phillyseaport.org/images/Cramp_Ship_Building_Company_Collection-PhillySeaport.pdf