Looking for plans for decent 16` Aluminium fishing boat

[etienne1963]

As a recreational fisherman I've owned a 14` which was too small and crowded yet economical to operate and easy to store and tow. I've owned a 17` and found you need a crew of 3 to launch and its difficult to store and heavy to tow long distance. I'm not really interested in travelling far offshore and average 7 to 10 nautical miles as that's where the fish is that I target. My boats have been glass and I've taken an interest in aluminium fishing boats but wonder how they will compare in our conditions and why they are not as popular in Cape Town as in other regions. I'm interested in a 16` as I would be able to launch with two crew and I would also be able to launch and fish our rivers. I'd think about a 15` but am not convinced. We have strict regulations that require 2 motors and I would want that from a safety POV. Also buoyancy regulations are very strict. I need to research the latest requirements.
I'd like to build my own boat. I need the challenge and it would give myself and my kids something to enjoy together. I'm hoping someone can guide me in this respect. I have facilities to bend , weld etc an Aluminium boat.
Thanking you.

[Squidly-Diddly]

Or could be operated independently.

Only question is where/how to mount the motor.

I guess you could hang it off the side like a canoe, or since you are already fabbing in aluminum, make a custom bracket.

[Mr Efficiency]

Interesting that the law requires twin motors for offshore boating in South Africa. Goes a long way toward explaining the popularity there of small power cats. 16 feet is probably the minimum size for a plate alloy boat, otherwise pressed or swaged thinner material becomes more attractive, but a different proposition build-wise. Australia leads the world by a comfortable margin with trailable aluminium powerboats design and manufacture, in that environment you wouldn't build a sixteen footer, there is just a glut of choice in available makes. A bit like the old postcard sentiment, "wish you were here" .

[etienne1963]

I'm beginning to think its going to be a challenge. I've heard a great deal about Australian fishing boats but wonder if their designs can be adapted for the extra weight of a second motor.

[cyclops2]

Put one light weight on the transom.
Put the main motor into a motor box in front of the transom.

I have a Aluminum 16' X 15" high transom fishing boat with a 9.9 & a 28 hp on it. True.
I have to be EXTREMELY carefull of wakes from large boats. Usually I just do the 9.9 hp.

Off shore REALLY needs a lot more length , beam & hull depth.....No 2nd chances out there very often.
You have those nasty Whites & worse yet. Bull sharks.

Bigger is better.

[etienne1963]

Originally Posted by cyclops2

Put one light weight on the transom.
Put the main motor into a motor box in front of the transom.

I have a Aluminum 16' X 15" high transom fishing boat with a 9.9 & a 28 hp on it. True.
I have to be EXTREMELY carefull of wakes from large boats. Usually I just do the 9.9 hp.

Off shore REALLY needs a lot more length , beam & hull depth.....No 2nd chances out there very often.
You have those nasty Whites & worse yet. Bull sharks.

Bigger is better.

Hhhmmmm.

No Bull Sharks but the Whites yes. And lots of whales.
Wanted a 16“ so I can fit two 30`s. And still get on the plane with 3 crew. Also for parking and towing. My boats have all been deep Vs. 16` is a popular size for recreational fishing to 10 Nautical miles. All glass boats though. No tinnies.

[cyclops2]

I SQUEEZE 2 adults 220 to 250 pounds each & 1 kid 60 to 100 pounds.
I stay only in waist deep water. Or life jackets on everyone in deeper stuff.

Boat, people & gear is CLOSE to legal limit.



Edit I am 1 of the 2 adults.

[etienne1963]

Love to see a pic of your boat. Ill post of my 17` which handles 5 at a push including myself as the skipper, tomorrow. Fishes comfotably 4 up at anchor. 3 up if trawling.

[Mr Efficiency]

Originally Posted by etienne1963

I'm beginning to think its going to be a challenge. I've heard a great deal about Australian fishing boats but wonder if their designs can be adapted for the extra weight of a second motor.

http://boatpoint.com.au/boats-for-sa...spx?R=11483162

Although an old design from as far back as the 60's, the Clark Abalone was a very seaworthy vessel and set up to take twins. Wet and a bit bumpy, but handled offshore remarkably well. By current standards the topsides a bit low, but not a problem, the full bow kept it from burying the nose. I ventured offshore many times in the 14 foot version and never felt unsafe.

[etienne1963]

Good looking boat. I love the wetwell too.

[cyclops2]

2 adults in the Clark.

I have had Squalls pop up & reach me with HIGH wind, BLACK clouds & driving rain in less than 5 minutes. My back was to it while fishing. Felt a cold breeze.
Turned around. CRAP!!!!!!! Motored to the downwind side of a nearby shoal. Anchored with ALL the line out.
Felt like Death was in the boat with me.

Almost forgot the best part. I was laying down on the centerline of that 14' rental boat. Waves were high enough that I looked up as they raced by. About 50 years ago.

[etienne1963]

Interestingly. After chatting with a couple of Cape Town fishermen on another forum two of the biggest negatives were the fact that the ali boats are very cold and that “ they slap the water like an old frying pan ”. I've seen some decent designs after a lot of googling and wonder if I shouldn't start off with a smaller river skiff at first. Maybe a 12 or 14`

[cyclops2]

They sweat like crazy on hot humid days & nights with cooler water.

[etienne1963]

This is not going well. I think the requirement is 60% buoyancy at full load. Which would require a great deal of foam. I'm beginning to understand why boat building is an exclusive club of artisans.

To calculate the buoyancy requirements for Cape Town waters 0.03 m3 of buoyancy material is required for every 27kgs. Therefore a boat of sa 750kgs including motors lisenced for a crew of 3 ( formulae is 75kgs per person ) will have a total mass of 975kgs.

975 ÷ 27 = 36.1111
* 0.03 = 1.0833

A further 25% is required for safety.
Therefore
1.0833 * 1.25 = 1.36 cubic metres of foam.

That's a further 48kgs of mass added at 35kgs / m3

From the regulations.


should be obvious that a simple standard amount of buoyancy will not be appropriate as vessels are constructed of various materials such as steel, aluminium, or from lightweight and buoyant materials such as foam sandwich construction. An individual calculation has to be made in every case to ensure that the vessel achieves the desired platform. An industry norm has been developed where 60% built-in buoyancy has been shown to be sufficient on wood and GRP constructions. SAMSA accepts this standard on categories B, C, D and E vessels so constructed.

The 60% means the following:
The volume (Mass) of water displaced by the buoyancy (i.e. the foam or bottles) provided inside the vessel must represent a figure of 60% of the gross weight of the vessel. Gross weight means; the weight of the vessel, engines, stores, fuel, persons etc.

[cyclops2]

This is starting to take away ALL the fun. Plus. You may get well into the construction only to suddenly realize you have designed in a problem that is difficult & expensive to correct.

Save a little longer and buy a ready to go boat.