Made one this winter,
based on designs seen at my dock. Didn't use the fender float. Broom end is a tee two feet wide with astroturf wraped around, then a 45 degree elbow about 3 feet up from the tee with a 10 foot straight after that. the 3 ends are capped so air tight, this provides enough flotation so you have to push the gizmoe down under the boat. Just leave on dock and write on it " Use and return to slip _______" no one complains.