I am thinking of using a 2m length of 5mm rod to make a marine danbuoy which I will use as a pick up buoy on a swinging mooring for my 30ft boat. This rod will pass through a float and have a weight attached to the base to keep it upright. Do you think that carbon fibre would be a suitable product for this purpose please and, if so, would a 5mm rod be appropriate or should it be a larger diameter?  Many thanks, Colin