I’m building a 1/48 scale City Class Civil War gunboat, the Carondelet, and my hull is flat bottomed just as the prototype. The hull is mostly solid foam sheathed in styrene. Then I covered it in bondo followed by a couple of layers of fiberglass cloth and marine grade resin. Anyhoos, the bottom is completely flat but should I add a couple of long ridges along the bottom to assist in keeping her going straight or should the twin rudders make that unnecessary? I don’t want to add them if they aren’t needed.
It will be a fairly slow moving vessel and used in calm ponds.