Which one out of these small multi-hull designs will be the best for my needs?

What boat would you choose?


  • Total voters
    13
I'm thinking of making the ECO750 / KD860 / KD 1000 demountable, because for me these boats offer the best in terms of volume and performance, even when you're looking for an old catamaran. More usable and more attractive than classic demountables from Richard Woods or Wharram or others. BK's boats are the most rational to build in 2024.

To illustrate my point:
Let's start with J. Wharram's TIKI 38, which, according to its owners, has no competitor on the market.
11.6m long by 6.2 wide for 3000kg. That sounds attractive on a forum. But when you visit two or three of them, as I did, you think about it four or six times.
In principle, it can be dismantled, but at 11.6m long, it's hard to fit on a 12m trailer.
2x 1.2T per hull + 1 pod plus dinghy + beams + mast + miscellaneous and yes the boat can be dismantled but it's a lot of work and never on the same trailer.
With a waterline of 9.6m, an impractical V-shaped hull and a freeboard that's flush with the water, the volumes are not very usable in relation to the numbers. So much so, in fact, that we quickly compare it to Bernd Kohler's KD105. One metre shorter in overall length, but one metre longer at the waterline, for half the weight. So more beautiful, more roomy, faster on the water, faster to build and all for much less. I reckon it will cost between €50 and €60,000 to build in France, with 2 helpers on hand to speed things up and save time on the building site. For a boat with the same level of finish as this one, offered second-hand at 92k€. Wharram Tiki 38 https://www.boat24.com/fr/voiliers/wharram/wharram-tiki-38/detail/562537/
I really like the Tiki. I have a lot of respect for them. Their owners are all exemplary sailors whom we appreciate and whom I like to have as friends. Except that for me the KD105 is a more rational choice than a TIKI38. And if you end up saying that you're not going to dismantle these boats because they're impractical in everyday use, you continue the comparison and end up with the KD1000, which is even more spacious and economical to build. And if you were to envisage living below the equator on a Tki 38, then the DUO1000 with a removable integral bimini would be a more rational choice for even less money.

I hope that my thoughts, born of long meditation and vain attempts to find the rare pearl, will enable you to make a quick choice. Reflection must give way to action, because the joy of an economical boat is incomparable to that of dreaming about it. Personally, if I were you (if I understand your needs and desires correctly), I'd either buy a KD860, build a KD860 or an Eagle24 if it has to be dismantled. It all depends on how you want to live with your future boat.

Building your own KD860 with the small modifications you want and two assistants would take you maybe only 4 months and would cost you the price of those considered for sale. It's a matter of choice and courage.

Laurent
 
@Eli I noticed a KD860 for sale today and was impressed by the quality of the fitout. It is hard to assess spaces when photographs are taking for marketing purposes, but it looks to have a lot of room for the size. Bernd Kohler Kd860: Sailing Catamaran for Sale | Timber Sail Boats | Boats Online | - Auckland NORTH ISLAND, North Island https://www.boatsonline.co.nz/boats-for-sale/used/sailing-boats/bernd-kohler-kd860/312201
Dear C. Dog,
I really appreciate your consideration, and the time you took to bring the fact that Oryx is for sale to my attention.
Oryx is an amazing boat indeed and one of the finest KD860's built. It also carries a sad legacy.

KD860 is one of the finest designs for a small cruising cat out there. I have decided to work with Mr. Bernd to custom design similar
and slightly bigger dual-mast catamaran, with some adjustments to improve crew safety and ease of handling at sea even further.
I also intend to eventually build it myself, to make a boat that I want - and also hopefully introduce some new ideas and another fresh
design to the existing pool of blue-water DYI cats.

I will keep this thread updated with the progress, and also post the resulting final design, if it reaches fruition.

Best Regards,
Eli.
 
I'm thinking of making the ECO750 / KD860 / KD 1000 demountable, because for me these boats offer the best in terms of volume and performance, even when you're looking for an old catamaran. More usable and more attractive than classic demountables from Richard Woods or Wharram or others. BK's boats are the most rational to build in 2024.

To illustrate my point:
Let's start with J. Wharram's TIKI 38, which, according to its owners, has no competitor on the market.
11.6m long by 6.2 wide for 3000kg. That sounds attractive on a forum. But when you visit two or three of them, as I did, you think about it four or six times.
In principle, it can be dismantled, but at 11.6m long, it's hard to fit on a 12m trailer.
2x 1.2T per hull + 1 pod plus dinghy + beams + mast + miscellaneous and yes the boat can be dismantled but it's a lot of work and never on the same trailer.
With a waterline of 9.6m, an impractical V-shaped hull and a freeboard that's flush with the water, the volumes are not very usable in relation to the numbers. So much so, in fact, that we quickly compare it to Bernd Kohler's KD105. One metre shorter in overall length, but one metre longer at the waterline, for half the weight. So more beautiful, more roomy, faster on the water, faster to build and all for much less. I reckon it will cost between €50 and €60,000 to build in France, with 2 helpers on hand to speed things up and save time on the building site. For a boat with the same level of finish as this one, offered second-hand at 92k€. Wharram Tiki 38 https://www.boat24.com/fr/voiliers/wharram/wharram-tiki-38/detail/562537/
I really like the Tiki. I have a lot of respect for them. Their owners are all exemplary sailors whom we appreciate and whom I like to have as friends. Except that for me the KD105 is a more rational choice than a TIKI38. And if you end up saying that you're not going to dismantle these boats because they're impractical in everyday use, you continue the comparison and end up with the KD1000, which is even more spacious and economical to build. And if you were to envisage living below the equator on a Tki 38, then the DUO1000 with a removable integral bimini would be a more rational choice for even less money.

I hope that my thoughts, born of long meditation and vain attempts to find the rare pearl, will enable you to make a quick choice. Reflection must give way to action, because the joy of an economical boat is incomparable to that of dreaming about it. Personally, if I were you (if I understand your needs and desires correctly), I'd either buy a KD860, build a KD860 or an Eagle24 if it has to be dismantled. It all depends on how you want to live with your future boat.

Building your own KD860 with the small modifications you want and two assistants would take you maybe only 4 months and would cost you the price of those considered for sale. It's a matter of choice and courage.

Laurent
Thanks a lot Laurent,

This common thought sharing provides a stream of fresh ideas to reflect upon.
I agree with you regarding Wharram designs compared to Bernd Kohler or Richard Woods.
With the advent of modern materials and building methods - such modern designs are a better and more economically sensible choice.
I am sure that in few years we will see even more fresh and pioneering designs - like Rob Denney's HarryProas, since they just make sense.

See my previous reply to C. Dog regarding my decision, hopefully I will manage to achieve the design criteria's and add something new to the already respectful portfolio of DYI
multi-hull designs.

Regards,
Eli.
 
Stating to righting again. Stel very bad.

Wharram's TIKI 38 same in side as Romany 34. 90% lese $ but beger inside than Wharram.

TIKI 30 more $ etc smaller inside etc.

Sailing Catamarans - Windsong - 9m deep V hull ocean cruiser


9000% biger than T30

BK1000 ?

Mike Waller Yacht Design | Waller 880 Catamaran (mikewalleryachts.com)

mush nicer in side. Not ply though. Quick maybe.

1x1 m cost $# + hours. See what you get for your $ and time. Inside ? speed ?

In Australia I can get fome for less than ply.
 
Hi all,

I thought I would give an update regarding the design selection process.

Since I began the search for a design that fits my needs, I have been corresponding with Ray, Rob, Bernd and Richard.
All have been very kind, and answered all my (multiple) questions in an informative way. I have also bought multiple study plans from them
and have been comparing those in depth. For the purpose of building the boat - I have obtained a permission to use a 9 meters long yard nearby,
which limits the length of the build to 9 meters, and unfortunately exempts the DUO1000 out of the possible build list.

Looking more in depth into the Bi-Plane extended KD860 Oryx and the "KD860 Open" designs, I thought a similar concept 9 meters long could suit my needs.
I began to make some sketches that I would like to share, together with my thoughts regarding this configuration.
The sketches are not completely to scale, and are based on a stretched to 9 meters "KD860 Open".

The helm is in the front of the saloon in a safe and protected from elements position, with good all-around visibility. All lines led to helm.
The access to the front deck is through a 60cm cockpit door making it safe and convenient to go to front, without the need to climb the hulls from outside.
The Bi-Plane rig clears the front of the boat, improves visibility and makes it a much better hanging out and working space during anchoring or docking.
Right of the helm is 2 meter "sofa", small NAV table and a table that converts to a bed.
There is enough space for a 120cm kitchen in the saloon, making cooking more sociable.

The Port side accommodates a twin bed positioned at a bridge deck level, and a full headroom shower with composting toilet.
The ship's only thru-hull and the water systems are on this side making it safe and easy to troubleshoot.
On the Starboard there is a twin bed, and storage/appliance room.

The stern has seating for 8 people and a platform for diving/dinghy. The Engine configuration is not final.
The composite lightweight Hard-Top spans all the living area and accommodates 3KW of solar panels and the mainsheets runners.
Because of the hard top, the Bi-Plane rig loses some sail area. I think I can live with the reduced performance.
I like the Bi-plane configuration, because it makes both building and sail handling easier, and lowers both the center of gravity and weight.
The hand-built carbon-fiberglass masts will be cheaper than a new aluminum mast, as well as the sails.

View attachment 195449

View attachment 195450

View attachment 195451


This picture is before the modification, to show the base design.

View attachment 195452


Any opinions or feedback are welcome.

Regards,
Eli.
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I think you should give the bi-plane rig serious consideration. Have a look at the virtues of this larger version

How about this motorsailer,..the 70 foot Saphira,....
Look what this older couple have come up with ! performance, ease of handling, and safety


Here is a very interesting story of the development of this vess
el
A Dream Takes Flight | Cruising World https://www.cruisingworld.com/people/a-dream-takes-flight/

And I imagine that the up-keep on this vessel could be far less than many comparable vessels,....only 2 sails, minimal rigging, two nice size engine rooms, etc, etc

I am totally impressed !!
 
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*********************************************


I think you should give the bi-plane rig serious consideration. Have a look at the virtues of this larger version

How about this motorsailer,..the 70 foot Saphira,....
Look what this older couple have come up with ! performance, ease of handling, and safety


Here is a very interesting story of the development of this vess
el
A Dream Takes Flight | Cruising World https://www.cruisingworld.com/people/a-dream-takes-flight/

And I imagine that the up-keep on this vessel could be far less than many comparable vessels,....only 2 sails, minimal rigging, two nice size engine rooms, etc, etc

I am totally impressed !!
Dear Brian,
Thank you for the information.

Yes, the bi-plane rig has some serious advantages. Especially for cruisers.
The article you shared provides some nice tips like longer booms for bigger
sail area, etc... The unobstructed view up front is just amazing.

This is why I intend to implement a bi-plane rig in my future build as well.
 

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or its named the duo105 hard to find as the site isnt working

Yes, that seems right. I'm not sure if the KD105 and the Duo 105 are the same? You can use the wayback machine to look at the old site, but that may not help much as the site was very hard to navigate even before it was broken.
 
Looks like Eli is not around. After almost two years he should be sailing according to his time estimate. In my experience, the construction time advertised is grossly unrealistic. That is, unless it is a fully equipped shop and the builder is a professional.
 
Looks like Eli is not around. After almost two years he should be sailing according to his time estimate. In my experience, the construction time advertised is grossly unrealistic. That is, unless it is a fully equipped shop and the builder is a professional.

Quite around. Though common sense choices took precedence.
After giving it a fair amount of thought, the ol' good advice of buying a used vessel
that suits the needs best, seems to be the best course of action for the average guy.

Priorities change, circumstances change - change is constant.
Building a niche design and investing years of life and resources might be less wise
than buying a used multi at half the price and selling it when the time comes for roughly what you paid.

Still - the process of pursuing a design, doing the research, and communicating with Bernd, Richard and others
taught me a lot about multis and various technical aspects of life at sea, which I'm very grateful for.

Fair winds,
Eli.
 
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i followed this thread and was wondering what design this is View attachment 206495

Looks a more accomodation focussed update of the KD 105. Largely by getting rid of the in hull cockpits of the first version. This design used to be called the Duo 105. Bernds design names are a little difficult to figure out how they relate to the overall design morphology. I've always liked this design but I'm not aware that any have been completed, the KD 860 seemingly more popular. Incidently when you compre the material list and specs to the 860 there is not much in it.

Duo 105-KD105 interior comp.jpg
 
Eli, whichever open bridge deck cat you build, do yourself a BIG favor:
companionways MUST face the STERN, NOT the center of the boat, NEVER!
(Trust me on this, we rtw-ed a Wharram Tangaroa MK1 cat in 7 years with them facing the center...same work & money - very often very terrible!)
& do yourself a second favour: forget electric auxiliary propulsion
(I am not a friend of dogmatism, but after more than 3 rtws...)
 
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