The alumacraft 12′ flat-bottom jon boat features 4 extruded aluminum ribs and pressed-in chines for strength and great tracking.. 25′ cabin cruiser . build your own floating paradise. outboard motor cart . move your outboard around and store easily with this cart. flat bottom jon boat. A simple to build, versatile classic flat bottom garvey, jon boat, duck boat. learn how to build a jon boat with our jon boat plans. these plans are available as a.