The Mud-Duck plans we got have sort of Jedelski wing airfoil with only the front 1/3rd a full depth box and a curved single surface to the T/E. I feel like continuing the bottom with a slightly concave sheet to the T/E to give a "proper" undercambered airfoil. It would also give a bit more rigidity to the wing for little weight penalty. Cardboard tube wheel hubs, yikes ! Seems the company that made the original kits sold the rights to someone who plans to rework them. Some were made of balsa, must have cost a slice of the rain forrest to produce. If you kept the timber-work rough and added an "Engaged" sign on the door you would have the original flying dunny
The Ag-Duck is more like it. Check out
www.rc-cropduster.com for some proper models of that ilk. If`n when you start your Mud Duck ,you know where to get the foam-board, get the floats on you can collect as much as you like at Loch Insh in Sept.