Double end power boats?

[achipmunk]

No wake is a good one. agree with Steven..

[dobsong]

Originally Posted by SailDesign

duluth,
Thanks for the mention. I think the problem with double-enders these days is that there are very few _motor_ boats (as opposed to power boats) being built. By that I mena true displacement boats. A double-ender will never plane, or even come close to it, and so people just aren't interested anymore.
I know that's a rather defeatist attitude, but after having Myrddin on the web for a while, I have had lots of enquiries (mostly from folks who want free plans) and they all go quiet when i mention a top speed of 7.5 or 8 knots if they're lucky. They seem to think 20-25 would be better. Ah-huh!

Steve "still likes them slow boats...."

Bartenders! up to 29' and 30+ knots!

[FAST FRED]

A double ender does look nice , BUT if I were looking for both practical and nice looking the round stern of the std tug does just fine.

The ability to pivot the boat against a wall or piling is a delight , and the aft deck doesn't loose too much space from the lack of corners , or a second pointy end.

FF

[tom28571]

Originally Posted by FAST FRED

A double ender does look nice , BUT if I were looking for both practical and nice looking the round stern of the std tug does just fine.

The ability to pivot the boat against a wall or piling is a delight , and the aft deck doesn't loose too much space from the lack of corners , or a second pointy end.

FF

Ah, Freddie, doing a lot of backing into walls are ye?

The one point that seems to be difficult to get across is that the shape of the stern above water has diddly effect on whether a boat will plane or not. It's only the shape of the part that meets the water that determines. Even there it is only the horizontal part aft that is important. The bottom can be truncated in points, rounded or like Mickey's ears if you like and if the boat meets the criteria stated by Tad earlier, it will plane.

[Tad]

Originally Posted by tom28571

the shape of the stern above water has diddly effect on whether a boat will plane or not.

Just for fun I'll be nit-picky and say I disagree...

If there was no boat at all above the planing surface...she would perform very well. Weight would be low and windage negligible. It would be great unless you met a wave or wanted to use the boat for something!

[marshmat]

Tad,
I think most of us have seen that photo of an outboard strapped to the back of an inverted kitchen table..... reportedly, it planes- fast- but I'd hate to meet a wave in such a thing.

As far as double ender power boats go- there was a comment what, five years ago on this thread, that people don't want a motor launch anymore. They want a powerboat, with the perceived ability to go 25-30 knots, even if the boat is horrifically thirsty and insanely uncomfortable at that speed. And frankly, when your marina bill is $2000-$3000 a year and your fuel bill is $10 a mile, someone who is only going out for occasional short trips a few times a season will often find it more economical to own a short, bulky boat that minimizes dock fees at the expense of terrible fuel mileage and rough-weather performance.

There is a market segment that I think would naturally be drawn to efficient displacement motor boats- older sailors contemplating a transition to low-physical-labour power cruising. But that doesn't seem to be a particularly big group, especially with the prevalence of powered sail-handling gear these days.

[tom28571]

Tad,

I don't know what to say. You have me there. Slow day in the San Juan's?

Matt,

There are a few of us on the forum who have that same goal in mind. Not always the same, but the main goal is how to be in the powerboating world and still afford to eat and raise the kids. The main division seems to be between those who are content to go slow and those who want the ability to cruise at twice or three times "hull speed" or higher if desired. Some want the higher to be a lot higher and some are content with a max of 20 knots or so. There is not a lot of consensus as witness the long running option one thread.

The double end vs transom thing does not even come into this argument. That is strictly an opinion on aesthetics unless one is talking about a true double ender, which is relegated to the displacement world. It's true that a few like the Bartender get past that restriction by cheating on the shape of the bottom and adding transom wings or other hidden contrivances. The Whio, featured in Woodenboat a couple years ago looks like a double ender but the designer cleverly hid a very nice planing hull under the water. For someone who doesn't much like pointy sterns on boats, sail or power, I'd say that Whio is the prettiest one I've seen.

[PAR]

I have a 39' double ended motor yacht with a 60 HP and an outboard hung rudder. It easy does slightly better then displacement speed with this current diesel/prop combination. It weighs in at 8 tons and I'm grateful it was designed with motoring efficiency in mind.

I remember "Whio" as well. An Australian built craft with clever weight reduction in her scantlings if memory serves me.

[dobsong]

Originally Posted by PAR

I have a 39' double ended motor yacht with a 60 HP and an outboard hung rudder. It easy does slightly better then displacement speed with this current diesel/prop combination. It weighs in at 8 tons and I'm grateful it was designed with motoring efficiency in mind.

I remember "Whio" as well. An Australian built craft with clever weight reduction in her scantlings if memory serves me.

Whio..... wasn't that NZ built?

[tom28571]

Yes, it is a Kiwi. A beautiful boat and apparently has impressive performance and seaworthy characteristics. I thought it also made some serious compromises to achieve these successes. An expensive and complex construction and spartan accommodations. Way too many compromises in my view, but horses for courses.

[dobsong]

Originally Posted by tom28571

Yes, it is a Kiwi. A beautiful boat and apparently has impressive performance and seaworthy characteristics. I thought it also made some serious compromises to achieve these successes. An expensive and complex construction and spartan accommodations. Way too many compromises in my view, but horses for courses.

Yep a boat built for a very specific purpose. That is safe, speedy, comfortable coastal passages and to be able to cope with some serious seas. All this seems to have been achieved with fuel consumption of 2 litres per hour at 10 knots. and around 7 litres per hour at 17 knots!

You can read about her at http://www.steamlaunch.co.nz/Whio.html

But as you say horses for courses..... some like em long and lean and some like em fat and hungry (bit like the "built for comfort... " opps i digress!)

[dobsong]

Originally Posted by tom28571

Yes, it is a Kiwi. A beautiful boat and apparently has impressive performance and seaworthy characteristics. I thought it also made some serious compromises to achieve these successes. An expensive and complex construction and spartan accommodations. Way too many compromises in my view, but horses for courses.

http://www.woodenboat-digital.com/wo...0060506/?pg=73

[PAR]

Oops, my bad about the country of origin. I too have reservations about some of the compromises made, but if it suits the client, it's well intended.

[334REG]

I just purchased a Saga 20, it's double ended and with it's MD2020 burns one quart diesel per hour at 7knts. There web site is Sagaboats.no

[334REG]

Check out Sagaboats.no