Once again, the genius of Phil Bolger reappears...in the form of the box keel to solve the height problem inside the cabin of a small boat. I've noodled around with the problem -- and the solution -- on my own mini-cruiser design. And I'm looking forward to seeing more when you start building! Can you clue us in on your self-steering system? I agree with the small refrigerator and solar for a few creature comforts. We're sailors, not backpackers! Let me know if you need some ideas...
The wind vane is the one used by the great French navigator Bernard Moitessier during his one and a half non-stop circumnavigations. In his inspiring book "The Long Way," he mentions that during his 35,000-mile and 10-month voyage, he almost never touched the helm.
There are other simpler alternatives that I believe could work, such as the sheet-to-tiller system. The German manufacturer Windpilot also has a small model that weighs only 16 kilograms (28 pounds), but this solution might interfere with a fundamental part of my design: the stern ladder that facilitates access from land or sea.
Here is a link to a robust construction of this pilot.
Thanks for the link, Pedro. It's very helpful, and Kevin's second post on self-steering is also great. With a low-cost LFP battery and some solar to keep it charged, a small tiller-pilot is a real option, even on a super small boat. Maybe I'll combine that with a "drive-by-wire" helm station from inside the cabin or anywhere on my boat.
I would like to add some notes about the design of Caracolita. It has been like designing two boats: one that floats, which is the upper part minus the keel, and the other is one of neutral or slightly negative buoyancy that we could call a "submarine." The floating part has a displacement of 370 kilos without load and 670 with crew, which I believe might be quite optimistic, but in flat-bottomed boats, this is not a major issue if we err in this data.
The submarine part has two sections: the stern volume is neutral because it will be filled with 100 liters of fresh water (at least at the start of a long journey...). The bow section has a volume of 260 kilos (for the 40 cm keel width version) that must be kept neutral by placing the same kilos of a heavy metal like steel or, preferably, lead in the flat bottom of this keel to offset this buoyancy. This ballast will also support the sail and right the boat in case of capsize. This ballast can be placed after launching the boat into the water and adjusted after equipping the sailboat and with the crew on board.
To reduce volume, I have designed this wide keel where we "walk" and narrow at the ends. It is not the most hydrodynamic design, but it is the lightest.
I have drawn three "widths" of the keel: a minimum of 40 cm or 15.7 inches with a displacement of 230 kg, another of 50 cm or 20 inches with 310 kilos, and another of 60 cm or 23.6 inches with 375 kilos, which can be very comfortable but seems excessive to me and also reduces the width of the cabin berth, which is one of the important aspects of this design. I think I will go for the 50 cm width, which is a good compromise.
This keel also has the advantage of being the "chassis on the ground" for the rest of the construction, saving on wood used.
And you can build the boat right side up and not have to worry about turning it! I'm assuming that you're not planning to ground your boat (at least, not on purpose), but wider might have an advantage. My "walkway" is 24 inches wide, for no reason other than convenience (and because the flat bottom is 6 feet wide) -- and my boat will need to be capable of being beached and run in very shallow water.
A creative and effective solution for turning a 15' 7" sailboat into a comfortable and genuinely useful cruiser. My first cruiser was an Alberg Typhoon and the only thing I really missed was standing headroom when getting dressed.
A very interesting and unique use of the Box Keel first introduced on the Jersey Skiff lifeboats (and still used on lifeguard boats today). I applaud you for thinking outside the box by making a place inside it to put your feet.
Once again, the genius of Phil Bolger reappears...in the form of the box keel to solve the height problem inside the cabin of a small boat. I've noodled around with the problem -- and the solution -- on my own mini-cruiser design. And I'm looking forward to seeing more when you start building! Can you clue us in on your self-steering system? I agree with the small refrigerator and solar for a few creature comforts. We're sailors, not backpackers! Let me know if you need some ideas...
The wind vane is the one used by the great French navigator Bernard Moitessier during his one and a half non-stop circumnavigations. In his inspiring book "The Long Way," he mentions that during his 35,000-mile and 10-month voyage, he almost never touched the helm.
There are other simpler alternatives that I believe could work, such as the sheet-to-tiller system. The German manufacturer Windpilot also has a small model that weighs only 16 kilograms (28 pounds), but this solution might interfere with a fundamental part of my design: the stern ladder that facilitates access from land or sea.
Here is a link to a robust construction of this pilot.
https://kevinboothbysailing.com/build-your-own-self-steering-windvane/
A small tiller pilot could also do the job. With two 160-watt photovoltaic panels, I don't think it would be a problem.
Thanks for the link, Pedro. It's very helpful, and Kevin's second post on self-steering is also great. With a low-cost LFP battery and some solar to keep it charged, a small tiller-pilot is a real option, even on a super small boat. Maybe I'll combine that with a "drive-by-wire" helm station from inside the cabin or anywhere on my boat.
I would like to add some notes about the design of Caracolita. It has been like designing two boats: one that floats, which is the upper part minus the keel, and the other is one of neutral or slightly negative buoyancy that we could call a "submarine." The floating part has a displacement of 370 kilos without load and 670 with crew, which I believe might be quite optimistic, but in flat-bottomed boats, this is not a major issue if we err in this data.
The submarine part has two sections: the stern volume is neutral because it will be filled with 100 liters of fresh water (at least at the start of a long journey...). The bow section has a volume of 260 kilos (for the 40 cm keel width version) that must be kept neutral by placing the same kilos of a heavy metal like steel or, preferably, lead in the flat bottom of this keel to offset this buoyancy. This ballast will also support the sail and right the boat in case of capsize. This ballast can be placed after launching the boat into the water and adjusted after equipping the sailboat and with the crew on board.
To reduce volume, I have designed this wide keel where we "walk" and narrow at the ends. It is not the most hydrodynamic design, but it is the lightest.
I have drawn three "widths" of the keel: a minimum of 40 cm or 15.7 inches with a displacement of 230 kg, another of 50 cm or 20 inches with 310 kilos, and another of 60 cm or 23.6 inches with 375 kilos, which can be very comfortable but seems excessive to me and also reduces the width of the cabin berth, which is one of the important aspects of this design. I think I will go for the 50 cm width, which is a good compromise.
This keel also has the advantage of being the "chassis on the ground" for the rest of the construction, saving on wood used.
https://photos.app.goo.gl/exvGAdbTrvHZrr5h9
And you can build the boat right side up and not have to worry about turning it! I'm assuming that you're not planning to ground your boat (at least, not on purpose), but wider might have an advantage. My "walkway" is 24 inches wide, for no reason other than convenience (and because the flat bottom is 6 feet wide) -- and my boat will need to be capable of being beached and run in very shallow water.
Intriguing! Best of luck and keep us apprised of your progress!
A creative and effective solution for turning a 15' 7" sailboat into a comfortable and genuinely useful cruiser. My first cruiser was an Alberg Typhoon and the only thing I really missed was standing headroom when getting dressed.
nice to have the footwell! I like! BestRoy
A very interesting and unique use of the Box Keel first introduced on the Jersey Skiff lifeboats (and still used on lifeguard boats today). I applaud you for thinking outside the box by making a place inside it to put your feet.