Affordable, long-term liveaboard?

Electric Marine Propulsion, Rim Drive Technologies

Have you guys given considerations to the 'rim drive' propulsion units?
More developed as bow thrusters, but still in need of development as propulsion units.

http://www.boatdesign.net/forums/propulsion/exciting-new-eps-thruster-propulsion-9432.html


http://www.yachtforums.com/forums/technical-discussion/3961-rim-driven-propellers.html

http://www.multihulls4us.com/forums/showthread.php?p=45220


http://www.yachtforums.com/forums/75536-post41.html

http://www.runningtideyachts.com/dynarig/

 

Chinese Junk

Yobarnacle, did you just call my future dreamboat Chinese junk?

Brian, 'rim drive' is quite fascinating. Do you know any Chinese 'rim drive' clone? I was looking for a Chinese 'paddle track propulsion'.

Haha, all jokes aside, I think junk rig makes great sense for an affordable live aboard. I had enough of quality premium brands and latest marine technologies. Only high-tech I will accept will be Internet and consumer electronics product.
All others shall be third world fishing boat mechanic level products only. I am tired of $1200 annual tune up for my twin 150hp Yamaha OB. Quality sails and fancy winches cost just as much as latest OB ownership. They are expensive to buy and they all break down from salt and UV anyways.
I need high tech design-engineered boat, utilizing proven low maintenance components while being mindful of my carbon footprint. Any ideas?

 

BTW, I read that our word Yacht came from Dutch Jaght from old Dutch Junko from Chinese Jun (boat) or Javanese Djong (boat) among other explanations.

I will be happy to dream about my junk rigged, unstayed-aft-mast, motorsailor, powered by Chinese junk hybrid propulsion, navigated by Chinese made Garmin with Chinese made iPad. My junk yacht I do need a Furuno fishfinder though. Is that made in China too?

 

I think the catamaran idea is excellent, but hovercraft implies fast, so you better train, or interbreed, the pilot fish to swim fast. i often wonder where the pilot fish go when a shark accelerates after prey, do they catch up, or join another shark? How then do they sort out the ‘pecking order’, who gets the prime position up by the jaws? But i digress.

The guy in the next desk to me at Boeing helped design and build/test the SES-100, and we did a bit of work developing this ‘sidewall’ system for other uses. In a water only use, this is a bit better than the ‘soft curtain’ systems, if only in directional stability. Hover craft generally rely on a large surface area for efficiency. The smaller the area, the higher the pressure, the higher the noise, and the higher the power density.

Various navies have experimented with ‘shark skin’ and ‘Dolphin Skin’ on their hulls, but both are dynamic, so a little bit hard to do mechanically.

There is a ‘engineering handbook’ that lists all the efficiencies for chain, gear, toothed belt reductions. I bought a small (yellow?) one for a few dollars from “Ace” a local hardware store. You can probably find one at a library too. Roller chain drive is usually the best, not a coincidence that we see it on bicycles, and human powered aircraft. Toothed belts and V belts are pretty bad, they need a lot of lateral tension to work properly. They are usually chosen for cheap, or a visually obvious life, ease of replacement, or on aircraft, a stated, specific, but limited life.

Gears are usually the longest lived, least bulky, and heaviest. The smaller the contact area the higher efficiency, but this also depends on power, and size requirements. Helicopter gearboxes are still nearly an art form, not engineering.

I don't think there is a systematic chart of propeller drive form, but some ‘rules’ do apply. Like airplane design, you pick a configuration for other reasons, and make it as efficient as possible. Cruise ships are very interested in overall economy, so tend to lead the way, but they are also interested in less draft, very low noise, and independent maneuverability, so these could be overriding factors. They seem to choose diesel/electric drive, using propeller pods, almost exclusively, but this may be influenced by other factors. Military ships are also interested in efficiency, even if only to go fast, and they use variable pitch propellers for acceleration as well.

Slow boats, hull speed, use long keels with imbedded shafts, probably because longitudinal stability is important, and skin friction is not. Planning boats, even fast boats like destroyers, cut away the rear hull to reduce surface friction to a minimum. Smaller boats also mess about trying to reduce shaft exposure, eventually getting to vertical drive shafts, OB, stern drives, and sail drives. I suspect the sail drive should be lower drag at slow speeds, no ‘base drag’ at the transom like a OB or stern drive.

What is an RC motor? Radio Control? Rotating Commutator? Radio Carbon?

Be aware, Lithium Iron batteries have a very delicate manufacturing process, and a poorly controlled one leaves particulates of Iron in the gel contained within it. As you charge/discharge such a cell, the fluid gets hot, the iron particulates get excited, and one will penetrate/damage the essential membrane inside the cell. Now the cell is ‘dead’. Cheap cells are usually subject to these kind of manufacturing faults, but expensive ones are not necessarily better, merely more expensive. Hence track record of a manufacturer, or constant personal surveillance (inspection) is necessary to ensure quality.

Chinese Photovoltaic panels suffer the same issues, cheap and poor efficiency, again usually a result of poor purity in the ingredients. Do not worry, they will both get better as financial and other pressures begin to be felt.

I have had bad experiences with the small (high speed?) diesel generators from China, not starting when needed. No obvious fault, i think its the injectors, or simple quality control. Personal visits to China indicate the indigenous low speed, heavy, diesels are fantastically reliable, running for years un-loved in a field, usually pumping something. These are very good, cheap, though very heavy too. I can recommend these, though perhaps not for a catamaran.

 

Sailor Alan, thanks for good explanation as usual.

I am thinking multi hull offshore cruiser for 2 to 4. Spartan, stable, economical and sustainable motorsailor. I can't make up my mind whether it should be a catamaran or a trimaran. The catamaran has stable large platform deck and private cabins but difficult to have large standing gathering space and reasonable windage. On the otherhand, the trimaran has more spacious galley/kitchen space but limited private berths. The waters I would like to sail would be PNW Inner Passage and South Pacific Islands ICW and Mediterranean doesn't sound bad either.

Anyway, 30-36' multihull with diesel/electric hybrid motorsailer seems doable. I am not quite settled on battery technology yet. Lead acid has reasonable install price and is still good for ballast, but LiFePO4 is stable and price competitive in long run. Regardless of who makes the diesel engine, it should be low RPM, non-turbo, low tech diesel then it is low maintenance and long life. Some Chinese made electric motors are quite reasonable in terms of power and durability. Obviously none of these are made for marine application. Therein lies possible cost increase during integration.

A RC motor is PMDC electric motors made for radio control airplane. Some of these are around 15HP equivalent at 10kw rating and only 5 lbs. Their high RPM, cooling and connection to propeller requires much experimentation. Even then durability and corrosion issues may be a deal breaker. http://www.hobbyking.com/hobbyking/...Max_150cc_Size_Brushless_Outrunner_Motor.html
Most promising electric motor would be Motenergy motors at the moment. http://www.thunderstruck-ev.com/12.5kw-brushless-sailboat-kit.html I would prefer AC or PMDC motor.

Many Chinese Lithium batteries have proven themselves in electric bicycle applications worldwide. Even Li-Pos are reasonable batteries provided you follow strict battery charging regiment, cell voltage balancing and fire bag LiFePO4 are considered stable and thus command higher price among Chinese batteries. Chinese have invested heavily in PV cells, lithium batteries and electric motor technologies. 4 out of top 5 volume PV manufacturers are Chinese, the other is Korean owned company in China. Tesla battery supplier Panasonic is manufactured in China. Rare earth magnet required for high quality electric motor are mostly mined from China, and China is restricting exporting strategic rare earth materials and forcing manufacturers to setup shop in China with Chinese manufacturers. This isn't cheaper suppliers issue any more.

I am not concerned with quality of Chinese products. Siemens and Sanyo still manufacture highest efficiency PV panels, but top Chinese PV panel manufacturers' quality is on par with Siemens and Sanyo. Chinese batteries are cheap because it doesn't follow Western distribution channels to get to us. Properly matched battery cells, good battery management circuitry and proper cell balancing will give 1000+ recharge cycles compared to 200+ recharge cycles on best US AGM batteries. Electric motors are still a concern because I can't find any good marinized PMDC motors. Diesel is easy. I can get low tech 50-100 HP Chinese agricultural diesel engines for small Japanese diesel price. Or, utilize VW TDI engines or Japanese small truck diesels instead. Only concern is cost of gears and hybrid transmission integration.

Even best iconic US product, Apple's iPhone, is manufactured in China along with all IBM servers now. So we can't discount Chinese products as cheap trash products any more. We need to be proactive in manufacturing our products here competitively but that is a different thread and different forum

 

The food preparation area doesn't HAVE to take up permanent space or be a designer galley. Don't think of a small boat as a floating apartment. It's a vehicle. Gear not actually in use is best stowed away. How many hours do you need to prepare food daily? I'm not talking about cooking time. a watched pot never boils. Aboard even larger boats, 100ft tug example, work is best accomplished sitting down. You get to use two hands sometimes while seated. Standing up you need to always hang on.

For food preparation, you need a table or counter to set things on and to cut on. The dining table or galley table is an excellent space for this, and has seating. For washing up, a tiny dollhouse sized stainless sink may be cute, but a wash bucket and rinse bucket set on deck by your feet is much more efficient. Sometimes you will grill outside. If you use a solar oven, that's outside. This gear is stowed when not in use. Why not the other galley items? I can go on, but I bet you see my point.

My galley is under cockpit hatches. If it's to rough to have those hatches open, it's too rough to cook. And cooking in fresh air don't stink up the quarters. I like cabbage. It keeps well un-refrigerated. Just peel off the dry leaves.
The one exception to semi-permanently installed, is a single burner sea-swing stove keeping the coffee hot. it's not in the galley, but near the helm where it's needed. It mounts like an oarlock. It's easy to stow away as well.

 

oh, instead of just batteries, check out super-capacitors. Infinitely rechargeable, and very very fast recharge.

 

Hi Yobarnacle.
If I was to sail with my son or my brother, then a 24-30' boat with camping-like set up would be sufficient and a single table for cooking and navigation is good enough. But when I have other family aboard (wife, daughter, grandkids) for a week or more then we would absolutely need all that space especially in Inner Passage or during Pacific crossing. This is different than a fishing trip over a weekend.
And, we like to cook and gather around to eat for a long time. Lazy folks. Multi hulls don't need swing mounted stove Girls like stable boat, lots of initial stability.
In my mono sport fishing boat, I can cook under hardtop on portable butane stove even though it has a standing galley in cabin. Just because we are in California and I like open air where action is. But if it is raining and cold, I rather be in enclosed protected space where water boils faster.

I didn't mention super capacitors, because they are super expensive and high charge/discharge rate is not needed for cruising application IMHO. In motorcycle racing or car regenerative braking/charging is only application where super capacitor may be needed. The circuit gets too complicated and expensive even if super capacitors are inexpensive IMO. Some LiPO batteries can be used for high discharge application. Some are claim to have up to 90C rating, but I doubt that is a true engineering specification from reputable manufacturer. I don't see that kind of technical specification from any reputable manufacturers. They seems to be prevalent in most RC hobby website, so I am guessing it may be RC hobby marketing talk where some degradation and occasional battery fire is acceptable. However, 3C-5C maybe possible in certain battery chemistry. My hybrid car can do 2C regenerative brake charging with NiMH battery pack.

Since my other requirements are trailer/transportability and semi displacement cruising, this precludes monohulls. Large converted tugboat or bartender may be fun for Inner Passage or ICW though.

 

Hi Noah.
My wife is the most feminine person I have ever met.
The main cabin of the Albin 'Intrepidos' formerly had vee berths with a table, a full galley and a standup head.
It now has a bathtub and this fall a chart desk lid for it. I believe she plans to iron blouses on it. There will be two tip out toilets, one is for liquids, the other composting. A quarter berth for a sickbay. For someone needs to be near the toilet. And an overstuffed easy chair for chitchat company. But the MAIN feature of the main cabin, is a swivel high-back and armrests captains chair on a substantial pedestal and facing a large ladies vanity/desk with strong lights and many mirrors. The only obvious odor of this area is my wife's perfume. She preferred THIS arrangement to the closet sized head and 5 feet of galley counter. The entire main cabin, half the boat is HER dressing room!
She likes the galley in a locker. Close the lid? It's clean.
Every man must please his OWN women.

 

My opinion only, for the duty you describe, i would choose a trimaran.

Start with something that looks like this, i.e. has this configuration and shape, watch the video.

http://smalltrimarans.com/blog/?p=10420

The new central hull would have a cross section a bit like a 'box keel' but where the 'keel' comes up to the arma level. It would be scaled up to about 35’ long and having a scaled down interior a bit like this.

http://multihulldesigns.com/designs_stock/38tri.html

This makes the central hull about 8’ wide, and with enough flair to stow the floats under the extensions when on the trailer.

Use mast extrusions for the beams, preferably fairly low if possible (see above). make them full width, and in sleeves in all 3 hulls.

I would go for a short mast, perhaps 10-12’ high to launch a paragliding parachute for sailing. Far less ‘turnover’ (heeling motion) and very fast down wind and off the wind, and easy to handle.

I do not understand the attraction of Diesel electric propulsion. Please explain?

i only designed one trimaran that got built, at 36’ long, and i learned a few things. It was heavy, far too heavy, so build light. The surface area was huge, far more than i anticipated, so even painting it was an issue. No great disadvantage to a generally power trimaran to a flat bottom.

Good advice about the gimbaled single burner, ours is an old kettle with a single burner brazed on the bottom, and hung from a wire hook.

 

I wish I had thought of that! I'm gonna steal this idea! A couple more gimbaled single burners come in handy at times.

For the regular sea-swing, a pyramid style food grater brazed to a small circular metal plate that fits inside the pot holder, makes a good cabin heater. I've heard of using inverted flower pots too. but they break.

Oh, my galley inside lockers isn't a pressurized white gas camp stove.
there's a microwave, a toaster oven, a large covered electric skillet, 2 crockpots, an electric pressure cooker, a drip coffee pot, a hot water kettle, A bagel toaster, an egg poacher, two blenders, a cake mixer, and a steamer/rice cooker. All electric.
Even in a normal home kitchen, most of these would live in a cupboard. All do on our boat.

 

Fast Economical Boats and Diesel

Sailor Alan, that is a one heck of a trimaran. 21 MPH with a 15hp motor on 16' long by 2'? wide hull. 224# hull weight and 600# displacement? Not too bad
I would prefer non-wave piercing. Just because of better boat handling and safety in bar crossing and square swell conditions we have in West coast. I hear small wave piercing bows can bury into backside of a swell once they get over it. 3' chop is fine with small wave piercing but 8-12' swell with 3' chop on top, which is typical for even Northern California water won't work with small wave piercing hull. Many fishing boats prefer blunt bow to surf down waves.

For a seaworthy, economical, fast boat check out Atkins Rescue Minor. 19'6" long by 5'8" seabright-tunnel hull. 25 hp motors 20 MPH. Much more seaworthy, much higher load carrying capability.
http://www.atkinboatplans.com/Utilities/RescueMinor.html
https://www.youtube.com/watch?v=ACJ-JDfEivM

The reason I like diesel for offshore live aboard cruiser is simple. Better fuel economy, easier availability worldwide, can burn most oil too, explosion safety, longer engine life, etc. Mostly because I can carry less fuel for longer range. Quite important if I want to cross long passage or go AWOL for a long time.

My preferred hull shape is double ended fat dory hull above water line with modified Seabright hull below water. This way it is very stable and most safety in all sea conditions, yet modified Seabright hull helps pounding and assist lift for semi-displacement speed I am seeking. Similar to this but with bartender-like stern and modified front end of seabright hull.

This is the transom of bartender. Following sea cannot lift the rear end and throw the boat forward. This will reduce pitch-pollinh for multihulls and yawing the monohull to set up for broaching. Yes there is small lift wings.


Sailor Alan, What do you think of my logic?
Yobarnacle, any advice since you should have more experience with this type of hull (bartender, trawler and barge).

 

Let's define affordable, liveaboard cruiser. I added cruiser since original poster wanted something he can cruise with his wife in protected water. The highjacker added environmental factor as an highest priority issue for an affordability. I think concept is good, nevermind the execution. Then the latest threadjacker (me) from the highjacker added offshore requirement and transportability/trailerability. So we are seeking an affordable, environmental, offshore, ocean cruiser live aboard that can be trailered or demounted.

Last few pages has raised minimalistic live aboard with wife/significant others. I can not buy the assumption that minimalistic cutting board and bucket next to a dining table is a live aboard suitable for couple or a family. That concept is like saying a tent is a house.
The true live aboard cruiser for a retired couple or a small family should be sufficiently furnished for living extended period away from the home in reasonable comfort. I know this is relative but I would say something Alaskan homesteader can live in reasonable comfort if moored in their property.

In 1892, William Andrews crossed Atlantic in "Dark Secret". It was 12' 9" long live aboard cruiser. NOT! Tom McNally crossed Atlantic in "Vera Hugh" in 1993 and it took him more than 134 days. Vera Hugh was 5'4.5" long The record was broken by Hugo Vihlen in same year on "Father's Day" 5'4" long offshore cruiser. Tom tried to do it again in "Vera Hugh II" but failed and has not been able to do it yet. "Vera Hugh II" is 3' 11".

http://www.yrvind.com/photos/

Obviously these were live aboard, offshore capable, cruisers. But, these are not what my happy-car-camping wife wants. She wants something that can handle some of our grandkids or other guests for dinner and safely cross oceans without too much chumming. So let's agree on Liveaboard cruiser = minimal house on the water. Cabin on the water?

These are best existing trimaran, catamaran and minimalistic tent on the water.
http://www.trimarans.com/boats/dragonfly-35/presentation.aspx

http://www.cat2fold.com/index.php?page=home


This would be a minimal tent cruiser for my wife. Meaning, she will go out for a weekend maybe but definitely not a week long cruise.
http://www.xs35cat.com/r33/en/rs33/design.asp


Yobarnacle, this one has a table for a galley. And this one is fast too.


None of the above meets my requirement for live aboard yet. It doesn't need to have a washing machine and an air-conditioning, but a microwave oven, a refrigerator, a bathroom with a shower and a desalinator is needed. A small air conditioner for a cabin would be nice though Remember cruising speed of 8-12 knots and top speed of 15 knots.

Any comments for boat plan or design concept? Lets set total budget at launch off to $250k, so average Westerner can sell their house and afford this boat. Although it would be more like $500k in reality. Monthly operating cost including fuel should be less than $2,000 so minimal fixed income couple can afford to live on it. What do you think?

 

Bartenders

https://en.wikipedia.org/wiki/30'_surf_rescue_boat

https://www.youtube.com/watch?v=v0uvKF9A43o

https://www.youtube.com/watch?v=Fh3DUi-EUZA

https://www.youtube.com/watch?v=C_EtUo5mXHw

 

I'm not planning to cross any more oceans by boat. I did that as my job for 42 years. Longest tow? New Orleans to New Orleans. 90 days at sea without touching land. Towed all the way to Gulf of Benin off coast of Nigeria. Rendezvoused with a lay barge that offloaded my cargo, and refueled us. Returned hence I came. Africa and back non-stop. MY little boats are for exploring gunkholes in the USA/Canada and use as minimal environmental footprint floating cabin for a little gold prospecting.
I'm happy to kibitz but our needs are different.