Hello Gentlemen and Ladies

[Just Harry]

I did read through many filament posts, here and elsewhere, but im still not exactly sure which to use for my purposes. I have spent days studying properties of filaments and have read about or watched different reviews and such. So my new CR-10 S5 arrives today and im ready to purchase some filament. I have designed several parts for my hobby which is RC Sailboats (racers). Not much interested in printing Vases, Action Figures, or some artistic accomplishment. Dont need too much advice on how to set-up or improve my printer quality with engineered addons. I pretty much have those bases covered.My parts have several requirements, which leads me to questions.
Requirements: 1. Parts will be subject to water imersion and salt water from time to time as well. 2. Parts will be subject to heat/sunlight while the boat is sitting, waiting to be used. We do try to use shade or a towel to cover. Many of our boat hulls and appendages are Carbon Fiber laminates. 3. Parts need to be light, stiff and strong, 4. For some parts I will need to do a split on the slicer and then bond. Most all parts used will have a purpose involving stress.I can engineer the right balance of lightness, strength, and to a degree, stiffness into the parts, but with the choice of materials available, it becomes a jungle as to choice, not so much brand, but type. It would be nice to use just one material for everything and I think I can, depending on the input I receive. I understand that my abilities and accomplishments will be limited by my printer type (FDM) and my printer quality. Its not a 5K or a 65K printer. So just to open up on filament, my sailing buddies are saying to use ABS and of course it seems a good base material to start with. I would definitely want to take advantage of using the Carbon mix on any material I use, so lets just say CARBON (insert filament type here). I am in the process of shopping the high performance heated bed option, so that should be considered. I will also add one of the all metal hot ends so i can use something close to 300c if necessary. And an enclosure for quality of print. My main concern is trying to print a "keel fin" It would either have to be a vertical print which would place the layering of the filament in the wrong direction for strength, and present a tenuous build for the printers abilities, or do a vertical split and lay the piece down on the bed. This would give me both the best filament alignment and provide a huge flat base to work from. Since the keel is dimensionally thin on the chord of the profile, this wold result in a rather flat finished piece. Yes, it is designed with a NACA profile, hence the split, and a good advantage for a very good print. The problem now becomes one of bonding. The keel would be approx 18 inches vertical height with the top 4 inches inserted into a Trunk inside the boat. The other 14 inches will extend down into the water with a maximum weight, torpedo shaped, lead ballast bulb, of 4 pounds on the bottom end. That keel has to be "STIFF". The less deflection the better. Now, there isnt any real point in placing the keel at a 90 degree angle with the weight hanging off the end to see how much deflection is involved. If the boat is sailing in the water and the healing angle goes more than something around 60 to 65 degrees it doesnt matter anyway as the boats performance is already degraded by the inefficiencies of the rest of the dynamics involved. Now, I need advice on what filament(s). Please.