The 'hull' is a sheet of 1/4 inch bass wood. sheathed in Evergreen scribed sheet. The deck was carved into alternating plates--actually engraved as I used my Dremel and a small grinding bit. The turret was formed from card board rings and a band and sheathed in 20 though plastic sheet. Rivets are Grandt Line or Tichy Train Group model railroad rivets, drilled and placed by hand. The stack is an Evergreen tube.
CSS Arkansas. Similar construction, but casement is a styrene box from scribed sheet. Boat davits are brass wire. 10 guns of various calibre were carried.
USS Shamrock is a union "double ender". The boat had a large gun fore and aft, paddle-wheels amidship and a bridge and rudders on each end. It was literally double-ended and could travel either direction with ease. Some models show what looks to be furled sails on the masts. I don't believe these boats were intended to be sailed. Some images do show some sort of canvas on the masts. I believe these were canvas duct work that was used to vent fresh air downward to the below-deck spaces.
Each end of the double ender had an 11 inch gun. The circular rails were used to shift the gun from side to side and to pivot the gun when firing out the side ports. I don't believe the guns could shoot directly fore and aft. The gun would pivot on the front point of the carriage and ride on the semi circle rail. To change to the opposite side, the front pin was unlocked and a rear pin was set (at the intersection of the semi-circular tracks. The gun would then swivel around the full circle, to be locked on the opposite side. Several smaller deck guns were carried. Four life boats were also mounted two each side just fore and aft of the paddle-wheels. (Or fore and fore or aft and aft as there really was no fore and aft!)