Composite ocean row boat advice

[OceanRowSolo]

Hello,

I'm looking at building a solo ocean row boat with a composite core construction. I'm thinking instead of using red cedar or similar plywood for the core, to use Corecell as the core, then a layer of kevlar (on the bottom), and carbon fiber all the way around. Interior would be carbon fiber with composite honeycomb panels at the forward and aft bulkheads.

My goal is a lightweight, strong craft. The design is approximately 23' LOA, 6' beam, 6' tall, 2.5' draft. It has forward and aft cabins creating watertight bulkheads. Typical weights for these are around 700 lbs. with a red cedar/carbon/kevlar construction.

Any thoughts or advice? Can I get away with not having to make an inner mold for the hull, instead vacuuming around just the rib layup? I appreciate greatly any advice or comments on any aspect of my project.

Thanks,

Wave Vidmar

You will get away with everything. Except LIGHTNING strikes not putting your lights out. CARBON CARBON, NO NO NO. What are the chances of a little bitty boat all by itself on tall waves being HIT? I would not worry very much. I am not going with you.

[D'ARTOIS]

Light weight and strong. Ok, that is justified, you have to row a bit more than 3000 nm.
I agree a bit with uncle Richard - when her remarks Carbon, Carbon, - what your motives are to use carbon fibres as a basic hull material.
What you need is a boat that suit your purposes. The mechanical properties of carbon are only superior in the way of tensile strength, not anything else.
What you need is a light hull with a high impactresistance and compressive strength in all directions.
The aramide (kevlar = productname of DUPONT) filaments as well as of those of carbon, could be combined in a so called hybrid woven, because of the fact that the bonding qualities of aramide are not that particular good, even with the use of epoxies as matrix material and therefore they are often integrated in an S-glass woven, reinforced with aramide and/or carbonfibers, arranged in a specific way in order to supply a cloth that is as strong and as light as possible.

In my opinion the best you could do is to shop around for technology. Plenty to find in books that are written to that purpose. Titles you will find plenty on the net. Check with the mondial epoxy suppliers like SP systems, if you dig deep in the subject you'll find a wealth of information - and than you might understand a bit more about the complex application-techniques of modern composites.

While in the USN, we were caught in a North Atlantic storm. DAMMIT- DO NOT go out there unless you are tired of lifes struggles! YOU have no idea of how continuously violent your insides become in 30 to 40 foot AVERAGE waves. A full sized air craft carrier was taking every so often, a wave covering almost 1/3 of the flight deck. ALL the destroyers came back to port with the outer bow plates stretched and pushed into the spaces between the frames, they looked like ****! Why they did not pop was a mystery. Have you ever been seasick for 10 days. AND we had the power of a destroyer to run with!!! I have no idea what you need to prove. But pick something more pleasant than getting caught in a non powered boat with EPRB's that DO NOT ALWAYS WORK. No one should ever have to endure a storm in a small boat. Forget the damn boat. Actually talk to, face to face, with people who have tried, failed, and succeded, about the wonderful storms they HAD to endure.

[Eric Sponberg]

Wave,

I disagree with Richard about carbon. Yes, it does conduct electricity, but when you think of the kind of target that you present overall, merely standing up in any kind of boat will likely make you as much of a target as standing up in a carbon boat--the risk is about the same.

I assisted Tori Murden in the rebuilding of her plywood rowboat a few years back in preparation for her successful transatlantic crossing (first woman and first American to row solo across the Atlantic.) At the beginning of her effort, we tried to convince her to get funding for a new carbon fiber rowboat, but the cost was going to be too high--so she recovered her old plywood boat. I helped her redesign and rebuild the boat, then wrote a design review of the project for Boatbuilding.com (design reviews section).

I have always advocated putting the accommodation in the center of the boat, not the ends. In a little boat, the ends pitch up and down much more than the middle, so the ends are to most uncomfortable place to live, sleep, cook, etc. In some preliminary designs that I had worked out, putting the accommodation in the middle and the rowing positions in front of and behind the central pod makes a lot of sense. In the middle of the boat, you have the most room and the least motion. Therefore, living aboard is much more tolerable.

This concept was employed by Ned Gillette when he rowed his aluminum row boat Sea Tomato from South America to Antarctica in the late 1980s. See National Geographic Vol. 175, No. 1, January 1989 for his story on the trip. The boat was 28' long and built out of aluminum. It had a central accommodation and it carried 4 people I think. It worked well. And if anything conducts lightning, it's aluminum. Yet he did OK.

You have probably read a number of books about open water rowing. One of the mistakes that I have seen in new designs is that they are way to shallow, and, therefore, roll over way too easily. This is the biggest drawback of making the boat too light, because the lighter it is, the shallower the hull is, and the more likely it is to roll over. If it does roll over, of course, it has to come back upright, so whatever weight you do have in the boat, it has to be down as low as possible so that upside down the boat is unstable and will reright itself.

There was a Frenchman who rowed across the Pacific in the early 1990s, Gerard d'Abovile, (he was a close friend and mentor of Tori's), and he had a very lightweight and shallow boat, and had a devil of a time trying to keep it rightside up! It would get rolled in the waves and was more stable upside down than rightside up. You may have read his book, "Alone: One man who braved the vast Pacific and won."

In the new boat that we had planned for Tori, I was envisioning also a very lightweight but deep narrow design so that there was room to keep supplies and weights down really low. We also contemplated carrying waterballast in tanks down low so that you could take on weight when the waves got really rough, but could pump it out in calm conditions. Unfortunately, we never got as far as a preliminary design.

I am discussing a new project right now with another client who wants to sail around the world in the smallest boat ever--under 12', and for that we are following the same principle--narrow and deep for seaworthiness and comfort.

Eric

I totally agree with your narrow and deep design. I tied myself into a bed and occasionaly the bed was airborne. Survival and stabitity are key. Actually, a shape like a slightly cooked hotdog is about as self righting as I have ever seen. That, with a couple of weighted sea anchors at each end is about as good as it gets in a storm. Still----------Bad luck is hell, all alone in a cylinder with a snorkel to exchange the air during Force 3 and higher. I really want to discourage people from this.-----At 12' a small thin sailing type keel offers a lot.

You may make the keel out of carbon and razor thin to keep the hull tracking straight. ---------I keep forgeting, extreme people in any activity have no concern over themselves. Attaining their goal is everything.

[yipster]

a boat like wave is looking at was on a exhibition here and was build rather crude in wood epoxy. did the atlantic tho. heard most of the rowing was done to follow the ocean streams in the right season. i'm not going but iff i'll use a sail