A maximalist outboard cruiser, why not?

That looks great TAD , but I would be willing to try the reverse deadrise , to get the prop out of a pocket , and perhaps gain the claimed efficiency of pushing on the water that has already been accelerated.

The claim of a VERY flat wake is useful particularly if the boat is to cruise at speed on todays waterways.

The 33' Latitude 46 Andreyale 33 is a piece of eye candy that is close to fitting in a box.

The 88hp Yanmar is claimed to cruise at 13K and top at 18!

With a larger engine that could make that 88hp on a cont basis , 18K cruise could be done , on 4 to 5 gph, my dream!!

With a 39ft boat with 3/4 ft less beam the fuel use could be even better , although weight would grow a bit.

FF

 

It is with great interest I see this thread mentioning the Atkin box keel concept. This has been discussed before and I learn a little more each time.
To me this hull form could possibly be my holy grail, moderate performance with minimal fuel consumption.

My limited observations of Atkin’s designs seem to point out a few common traits. The hulls were slim by modern standards but not radically so. He clearly believed in minimizing top hamper. He was not pushing the fuel consumption envelope by extreme attention to weight. His designs seem to indicate that if careful consideration to modern lighter weight construction methodology was followed there would be more than sufficient latitude to weigh down the boat with all the creature comforts that we all know creep aboard a boat over time.

It is my hypothesis that Atkin accomplished this by setting rather moderate performance goals and optimizing everything to accomplish his goals. He seemed quite at tentative to careful hull sculpting to achieve good clean waterflow to a specific propeller turning at specific revolutions by motors of rather limited power.

To me this suggests an almost intuative grasp of the art that charactorizes the best of the science of elegant engineering. It is with great interest I have observed several attempts to recreate the “magic” in recent years. There have been several noticeable successes and several attempts that were not quite as successful. I find it frustrating that several promising projects are stalled out at near completion. I can not cast stones however as my glass house is filled with projects almost done.

I apologize if I have engaged in a wee bit of thread hijacking and will close with another opinion that if the power plant required does not offend your sensibilities diesel is the way to go. The higher compression of the motors coupled with the greater chemical energy in a fuel that is so closely linked to home heating as to be politically protected make it a slam dunk to me.

 

I believe that the traditional gas vs diesel argument has been turned on it's head by new economic realities. It used to be that with diesel costing the same or just pennies more than gasoline, one could amortise the extra cost of the engine over the years through lower fuel bills and lower maintenance costs. Now diesel has gone up to as much as a dollar a gallon differential over 87 octane due to ULSD mandates and refinery under capacity. I have heard that the same thing is happening in Europe as well. Unless the Clean Air Acts are soon to be repealed the price of diesel will remain high. Home heating oil is not the same product as low sulphur diesel and the days of running it in your boat are soon to end. The new low emission common rail engines are not your old 2-stroke DD, they have very strict fuel requirements and high sulphur fuel is not one of them. Emission mandates will soon have us all on ULSD anyway.

Gasoline also has a political constituency: everyone who drives a car! Those folks will demand that the price of transportation be kept as low as possible and they will be able to lower their consumption to lower demand as prices rise. They can eliminate discretionary driving and eventually buy more fuel efficient cars. But not the diesel users, most diesel is used by industry, truckers, construction equipment and the like. They cannot cut down their usage or they have no business, the must keep buying no matter what the price. They are a captive market and the oil companies know it and will continue to exploit it.

The new gasoline outboards both 2 and 4 stroke have very high power to weight ratios and are extremely reliable. The US Coast Guard has over 10,000 hours on many of their outboards, more than a lifetime of recreational use. Service costs are about what you would expect from a new car: next to nothing. These motors are not what was hung off of transoms 25 years ago, the computer has hit in a big way. The same with generator technology, you can gang a pair of Honda air-cooled 3.5kw remote start units for a fraction of the cost and weight of a similar sized diesel set.

I am not against diesel, far from it. I just think old verities need to be periodically pulled out and re-examined when the world around us changes.

 

To put this thread back on track, I have found a Garden design that shows what I am thinking of. It is called simply Motor Cruiser, but the nameboard on the plan shows Westwind. She is 38' X 9' with a forward head and hanging locker and a small aft cuddy. A modernised version of this with a slightly changed layout would suit very well I think, at least it is worthy of investigation. He designed it around a 600cu in diesel he had around the shop, but I wonder if a different engine could be used. Perhaps a lighter diesel or an I/O ?

 

Perhaps I would differ with you on the perception that the lobbies that represent transportation, industrial, agricultural, and construction interests are not perhaps the equal of motorists but it really matters not.

By all means use outboards and gasoline if they are the most suitable choice for the proposed vessel discussed. It would be of great interest to me if those more knowledgeable than myself could weigh in regarding available torque and propeller choices for the maxicruiser. Best of luck with your proposed boat. It must be exciting to contemplate a dream coming true.

 

"The US Coast Guard has over 10,000 hours on many of their outboards, more than a lifetime of recreational use."

With how many rebuilds , at what intervals?

With enough wrenching talent and a large enough parts supply , even a weedwacker will run 10,000 hours , although it will be rebuilt 500 to 1000 times.

The 4 strokes are simply car engines , which at 200,000 miles would relate to about 4000 hours in a boat , although the usual high throttle settings of the Coastie Kids will reduce the service life a great deal.

For a place with assured fuel supply , and maint aviliable a gas engine would be a great choice, for cruising ??? Maybe.

FF

 

Why can't you take that Rio Hondo 40 S, and make it a motor boat. Has round hull, long, fits on a trailer, lite, easy to build, etc. Put a nice motor, stabilizing stuff and go. Put it in and cruse from LA to alaska? IS that too simple.
The boat looks good and looks like it would be fun to build.

 

"just keep under 26k total weight,"

In the USA the trick would be to get a truck that has a large "condo" behind the cab. These can be found as big as 150 inches long .

The KEY is to have a bunk , stove and head.

Then its a "Motorhome" and insurance is cheap, there is no 26,000lb rule , or special drivers license required.

Many retirees (like myself) drive old "Greyhounds" or other converted busses , that run 45 ft long , and some 50,000lbs , no problem.

To "motorhome" a commercial vehicle only requires a trip to the local cop shop or DMV for the inspection.

Towing anything BIG & Heavy is what these trucks were built to do , a cruising O-B or diesel that goes on a trailer would hardly get it warm.

BUT NO COMMERCIAL tows , with a MH , your boat or a buddy's only.

FF

 

On the propulsion note, I agree with Westfield that outboards are getting a lot better and more reliable. They have their place and the sheer variety of them is a very big point in favour- you can almost always find at least one that will suit.
I am, however, still recommending gas sterndrives to friends, at least in the 135-plus hp class. Yes, they are bulky and take up room in the boat. Yes, they are still basically the same blocks as 15 years ago (or more). But parts for an Alpha can be obtained anywhere for reasonable prices, and any good mechanic can do virtually all conceivable maintenance to a 4.3 V6 (a relatively sturdy, long-lived engine compared to some of the light, high-revving O/Bs). Outboards have a finite market life, just like cars do- every few years, they get redesigned with new parts. Those parts seem to become horrifically expensive in short order on a lot of newer models. And the computers are proprietary and can't always be diagnosed by a non-dealer. So conventional block it is for me, for the time being, until I see some reasonable prices for fixing up the high-tech O/Bs when they go.

On Fred's suggestion of a motorhome-truck: If your DMV will allow this, go for it. Adds a big convenience factor too, no hotels to worry about. Canadians be warned, though, you can't get away with that here. In Ontario, over 11,000 kg gross or 4600 kg towed means a Class A licence (sometimes people sneak 5-tonne house trailers by under a Class G, but if you do something stupid while doing so, the cops will take your lack of the proper licence into consideration when charging you).

 

Hi, interesting proposal and discussion.
I did a design for the Wooden Boat design competition for using a Subaru inboard motor in a boat. I chose to do a modern plywood interpretation of the old Elco 26 footer, see attached photos of part of the hand drawn plans.
The design would also be suitable for a pair of outboards of between 60 and 90 hp each located below the stern seat in the cockpit with a reinforced transiom at the forward edge of the seat and cutouts in the transom to allow for them to tilt up. This design concept could easily be enlarged to around 35 feet and would then allow sufficient volume for your purposes, although I think that the accommodation shown would be adequate for living aboard for the periods that you are suggesting. To improve seakeeping in a rough sea then a V bottom could be installed in place of the flat bottom panel, the actual deadrise angle depending on a tradeoff between seakindliness, depth and performance. As shown with a 90hp subaru I calculated a cruising speed of about 12 knots and a max of 14 to 15. I think that these figures are probably conservative. As indicated she was designed to go on a triple axle trailer and was 8 foot beam for legal trailering. Weight was designed at about 3800 pounds.

 

I feel it will only be a matter of time before the newest series of auto DIESELS will be modified to use on an outboard leg.

The advantage over an out drive is the EZ removal for service , or change up to a different motor.

Unfortuniatly the newest series of electric injected engines wont run well on household fuel.

DAMN,

FF

 

Stretch a Great Alaskan skiff?

Thought I would bring this thread back from the dead. Family issues and the crappy economy put our plans on hold for a while and means and needs changed. I haven't given up on the concept, just downsized.

We are now looking for a smaller cruiser, big C-Dory sort of boat: a bigger version of a Rosebrough 246 that we could use for the Loop, and also PNW. I am thinking long and hard about the Great Alaskan, a version of the Tolman Jumbo that would be about 32' with another 2 1/2' hull extension. The basic boat is 26' with an 8.5' beam and has 5" chine flats. The dead rise is 13* at the transom. I would like to lengthen the hull, widen it a bit to 9' at the waterline and add a large cabin.

Just for the sake of discussion, what would be the best way to widen this hull? Widen the bottom and keep dead rise the same? Widen the hull at the chine flats only? Widen the hull at the bottom and change the dead rise? Or some combination of all? I figure that I would be moderately loaded for a Tolman, they are light boats, and just wondered about the effects of the various options given a baseline of the stock 26' to 28' Tolmanesque Great Alaskan.

 

I too am interested in longer skinnier boats you could cruise in for a couple days and not break the budget. I like the seabright looking tunnel hull. Funny I happened across this because Renn Tolman was workign hard up until the time of his passing this summer on this concept. I think the lines for the boat were autocaded and probably one could be built by a knowledgeable builder. I think there was more written somewhere on the other site but this is what I got from steve dampier (renns words)

"Sure, it may just be time to leak this (old) new design to the press. Not quite ready to sell the plan. I have all the numbers and the how-to but need a pamphlet of instructions. Have sent it to Maine for Jim Shula to look at to think about CNC kits. . . A couple of more comments on the design. There will doubtless those among you who will say OH, that is an L boat. (Like the N word, I refuse to utter the whole word -- we don't like L boats hereabouts.) Well, yes and no. Maybe the profile, the rockered bottom with the flattish after sections and the plumb-ish bowstem. But has any one seen a true L boat with a hard chine, much less one with a chine flat, which mine and other Homer boats are famous for? The thinking on such a hull is it will travel happily at perhaps double true displacement speed (10- 12 kts.), but with sufficient power it will read back on its hind legs and plane to get you there before the restaurant closes, etc. But if you want to go fast habitually, just go to a full planing prismatic hull like most of the world. . . Another reason behind this deign as an alternative to my dory style skiffs is the very wide (88-inch) bottom, which will yield the volume for a truly commodious cabin. Compare to a Jumbo at 72 inches."

I guess we are at the point in time you cant just say tolman skiff anymore. since his boats go from 18 - 20 ft standards to 21-24 foot widebodys to 26 and 27 foot jumbo hulls. and then he had his atkin type hull prototype and now his trawler design.

 

Akins SeaBrigth Power Boat Performance

I take if from the discussion that Tolman's (Lord give him rest on Fiddler's Green) conclusions about the Atkin inspired Seabright are not well known?

The very, VERY narrow performance envelope of the skiff was so small that the skiff would only be useful in an inland, protected, fair weather lagoon, bay or bight. It was not able to take anything of a following sea due to slew and steerage problems; was not good into a head sea of any amplitude due to the balance between the tunnel, keel, and slender bow forms; and was no fuel efficient miracle in any speed range. IF you pushed this particular hull too fast the entire tunnel would ventilate and the prop would loose both push and the resulting steering loss could be a little dangerous.

It was essentially an interesting experiment but not one that revealed a new hull form of any reason to emulate; virtually all the claimed attributes, except running in 'skinny' water were overblown and jets do that job better with almost any hull form.

The idea of smaller displacement 'pocket' cruiser is of course appealing but that doesn't necessarily imply very shallow water. That is the one 'thing' the shape did reasonably well, but even than was predicated on the Atkins era engines as a given; outboards render this design prerequisite obsolete.

Like RS-232 as an electronic comm. standard; it worked for its time and place but no one is going to give up 10Base-T (or more) to 'go backward' in technology. So the Atkins Seabright (Rescue Minor) is mostly a branch on the tree of marine design growth.

The tunnel/pocket prop & keel design shown above, (several years ago) is a successful design and is proven in open ocean use in several versions including commercial fishing in Bristol Bay in SC Alaska where the design is nearly commonplace. There, it is used to propel reasonably shoal draft boats that will also take open ocean seas and haul good loads; in all sea conditions.

It is possible that a very scaled up version with a hp/wt ratio and design speed inside the hull form's limits would yield a viable design (D.Gerr's version??) but, unless the boat were confined to the inland waterways I think the hull form's seakeeping is still in question for a reliable cruiser?

Just an update on the Tolman/Atkins experiment, I live a couple of hours from Renn's old shop and have heard much of the experiment but not much good about its conclusion, including his continued failure, before his passing, to sell the prototype.

Cheers,
Kevin Morin
Kenai, AK

 

If we are going to have a permitted oversize load for width, why be limited to 65' in length?

BEWARE,

The various states limit the total length of the tow AND towing vehicle combined.

65 in some states 75 out west and 55 in the NE is common.

Commercial towers , the for hire 18 wheeler , are much less restricted.

Having a 39 ft boat to be transported in a Sea Land box or a boat trailer ,on my board for a decade , be sure you decide WHO will tow the boat.


My decision was an old 18 wheeler with a sleeper .

The unit can then be registered as an RV , so initial cost and insurance would be minor.

But of course one would still be limited to the non commercial length rules .

NO CDL, no huge insurance bill, and the ability to use the tow truck as a camper enroute might make up for the size restrictions.

The Atkins box keel , reverse deadrise boats are known for seaworthy and sea kindle use , with little loss of performance with huge fish loads.

The reverse deadrise does not seem to have the downside of loosing efficiency like a tunnel hull.

They seem to work best with a SL of 2.5 or less , so if that is the speed range you desire , go for it.

The easy ability to take the beach could be a big asset for remote cruising , or even in our over regulated, crowded local waters.

Above SL 3 a full plaining boat hull will give a better ride , with the usual huge fuel bill.