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??? I joined this group due to my interest in the KD860 and it's big brother the 980 for extended ocean cruising of the circumnavigation type..... though that is not a specific goal.??? Being a junk rig enthusiast, Pete Hill's Oryx led me to consider this boat as an option.??? Multihull is a non-negotiable for me, and ultimately junk rig is also due to the ease and safety, and many other factors that make it the best rig for short handing / single handing.?? I've been looking at trimarans, specifically Searunners and Cross boats, and while they are convertible, it's not a simple task, and the mast height drives the cost of free standing masts up rapidly, though I fundamentally prefer a single rig.? Performance is NOT a priority for me, however the modern cambered and split junk rigs perform on par overall with Bermuda rigs if properly designed, and take a fraction of the effort, hardware, etc. ???? What is pushing me toward Bernd's KD860 also is the smooth curved cabin top, rather than the chopped up deckhouse designs with all kinds of corners to create wind resistance / turbulence.?? I've concluded the obvious.... that a cat has two load bearing hulls instead of one? hull and two outriggers.?? This adds up not only to more load capacity, but also more internal space. ???? I have grave reservations about bridge deck clearance...... My calcs show about 19", but they are a bit crude, based on measuring drawings.?? Cabin height does not bother me, as this is a sitting area, but pounding when driving to windward is something that I cannot put up with.??? Both Bernd and Richard Wood build boats of similar size and bridge deck clearance..... I like Bernd's better based on the smooth contour, and other factors.?? What is lacking in the KD860 is any forward visibility inside the boat, except in the berth rooms.? To be an acceptable choice for me, it would be necessary to remedy that.? Pete Hill installed a plexiglass bubble in the saloon, obviously for that reason.? I'm imagining an aircraft style streamlined canopy forward over one of the areas that is designated as a berth........I don't need two.?? These are fairly easily blown, and it would fair into the smooth forward sloping roof, providing a wide field of view.?? ???? I'm interested in accounts of real world oceanic experience in the KD860 and it's variants......... How much pounding, and under what circumstances??? I'm not a guy to "drive" a boat hard to windward relentlessly for example......? have no reason not to back off, and I do not live by schedules.??? This boat attracts me partly because of it's diminutive size, as I will be single handing a lot.? I don't need a huge boat, I don't want one. What I want is a capable boat with good load capacity that won't let me down when I make bad choices... we all do.?? ???? I'm also concerned about the AV panels, which are one of the main "features" of this boat.? Do they really work as claimed?? Pete Hill lost at least one and claimed he couldn't tell the difference.? Having to install dagger boards "after the fact" does not appeal to me. ???????????????????????????????????????????????????????????????????? H.W.
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Hi. I mean no offence, but the type of boat you describe only exists in an alternate reality.? If you want load carying ability and pleasant motion to windward, a monohull is the boat of choice. If you want to circumnavigate in a catamaran, 8.6m is too small when you consider the required payload. If you want safety in a multihull, performance is a priority unfortunately. light weight, windward ability etc. Installing a junk rig on a boat not designed for it, is a major engineering exercise. But if installing dagger boards after the fact is unappealing. how are you going to cope with the amount of design modification and construction work that would be required to turn this stock design into your dream ship? As for bridge deck clearance the kd860 is textbook @ approx 6% of w/l length @ the lowest point and more under the cockpit, were you need it most, how much do you require? As far as I know Pete Hill is using mini keels, and had one fall off, with no noticeable difference, not the AV panels. As for your rig, I don't want to weigh into the debate about efficiency, however your modern cambered junk rig is going to take a huge effort to design, build, and get working properly, as opposed to installing an bermudan rig with essentially off the shelf components. It certainly is something for the very motivated enthusiast. I don't won't to appear negative, but as they say, all boats are a compromise and the one your after is not the Kd860 or perhaps any mulltihull that would be seaworthy. I own a Kd860, and although I am very happy with it's performance, it certainly won't do what you want, from my experience. Anyway, good luck with the design hunting.
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Andrew:
??? I think you misconstrued my intentions.........or perhaps I
don't communicate very clearly in print.?? When I used the term
"circumnavigation", I did not mean it in the sense of loading up a
huge amount of supplies and racing around the world, I rather
meant that the sailing I would like to do will involve long
passages, such as the Pacific for example.??? Passages that unless
things go very wrong should involve weeks, not months.? I think
I'm hearing you saying that the 860 is really just a coastal day
sailor and weekender, perhaps only suited for trips of a week or
10 days, that nobody in their right mind would consider taking it
on the ARC or the Puddle Jump, etc.????
???? I'm not at all sure what Bernd includes in the "empty weight"
of about 2 tons, or what permanent items must be deducted from the
approximate ton and a quarter of payload.? It would be interesting
to know what the real world weight of one of these boats is with
no supplies, spares, food, water, fuel, engine nav and radio
equipment, batteries, solar panels, pretty much just the bare boat
& rig & sails, with just basic interior fixtures such as
cushions in the berth area and saloon, a C-head, basic galley sink
and stove.
??? Two tons (1800 kg) is not a lot of boat............. if by
contrast one looks at Richard Wood's boats, foot for foot, they
show heavier weights, and lighter payloads.?? My suspicion is that
the two designers are listing empty weights that are not exactly
the same meaning, the result being that Bernd's boat has the
appearance of having a much greater payload.
??? Pete's boat as you know was stretched to 10M (33 feet), a 16%
increase in length over all, but it apparently easily carried all
necessary supplies for two people for the sort of voyaging I plan
to do.?? I presume that the increase in the size of the bridge
deck cabin, and the weight of the biplane junk rig, probably
resulted in no or very little increase in actual payload.
??? I won't argue the merits of the junk rig here......... That's
pointless, except to say that Oryx is obviously seaworthy with a
biplane junk rig, so obviously it's doable.
??? As far as basic design, Bernd's gotten everything right in my
opinion for a small economical seaworthy cat, from the flat hull
bottoms to the unbroken curve of the cabin top, to the bridge deck
clearance, and less than standing height in the saloon, where you
normally sit anyway.?? The KD860 and it's variants make all the
right choices in my opinion.??? As someone who is primarily a
single hander, it appears nearly ideal.?? I've had a belly full of
monohulls.? There is a better way, but the challenge of making a
cat work well in small sizes is not small challenge, and Bernd has
done what in my opinion is a very good job of it.
????????????????????????????????????????????????????????????????????????????????????
H.W.
On 11/22/2017 04:57 PM, andrewklees@... [k-designs]
wrote:
toggle quoted message
Show quoted text
?
Hi. I mean no offence, but the type of boat you describe
only exists in an alternate reality.?
If you want load carying ability and pleasant motion to
windward, a monohull is the boat of choice.
If you want to circumnavigate in a catamaran, 8.6m is
too small when you consider the required payload.
If you want safety in a multihull, performance is a
priority unfortunately. light weight, windward ability
etc.
Installing a junk rig on a boat not designed for it, is
a major engineering exercise. But if installing dagger
boards after the fact is unappealing. how are you going to
cope with the amount of design modification and
construction work that would be required to turn this
stock design into your dream ship?
As for bridge deck clearance the kd860 is textbook @
approx 6% of w/l length @ the lowest point and more under
the cockpit, were you need it most, how much do you
require?
As far as I know Pete Hill is using mini keels, and had
one fall off, with no noticeable difference, not the AV
panels.
As for your rig, I don't want to weigh into the debate
about efficiency, however your modern cambered junk rig is
going to take a huge effort to design, build, and get
working properly, as opposed to installing an bermudan rig
with essentially off the shelf components. It certainly is
something for the very motivated enthusiast.
I don't won't to appear negative, but as they say, all
boats are a compromise and the one your after is not the
Kd860 or perhaps any mulltihull that would be seaworthy.
I own a Kd860, and although I am very happy with it's
performance, it certainly won't do what you want, from my
experience.
Anyway, good luck with the design hunting.
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So after all I will give my sermon to your questions, uncertainties to. I declare the boat as a seagoing/coastal cruiser. Direct to your question weigth. I would build the boat with a weight of 1400 kg. First; because of my experience I know how to built light. Most builders ad unnecessary weight and when it is smearing the rest of the Epoxy in the pot somewhere. Example is my PELICAN. I give an empty weigth of 2000 kg The boat was on the scale of the kran exaxt 2000 kg. I give always the load waterline, for the KD 860 with 2800kg. Which means you can add another 1400kg. This is without rigging, deck gear etc. Distance waterline bridge deck as shown 600 and 700mm from the cockpit. The bridge deck starts far aft to prevent to get water (not spray) over the deck. The anti vortex panels are so strong that almost nothing can break them. See picture on the Pelican album. We where taking the boat out the ice because of shifting wind direct. You can see in the ice the form from the underwatership with antivortex panels. We where sailing to windward with these as any good monmaran ( many persons withnessd this) We sailed as high on the wind as a "Spectra" from Shuttleword with big daggerboards. But, here comes the point, the work not as effective as board in very low windspeeds, and the chines of the hulls have to be as sharp as cou can make them. After we added the glass fiber to the hulls (radius chine 5mm, otherwise you can not get the glass fiber good around the chine) we added Epoxy with a lot of fused silica and made "sharp coners " again. All new aircrafts use the anti vortex panels now again (winglets is the same). I designed the whole boat for good windward performance as you mentioned without a deckhouse. Smaller catamarans crossed the oceans and sailed around the world. Including a Wharram 6,5m and a Heavenly Twin. The couple on the Heaven Twin had the bad luck to be in a storm in the Aguela stream. Nothing whorser as that. The bridgeck distance from the boat was by the way full loaden 300mm. Not cabable to look forward: you gave already one solution with a dome. Besides when I seat on the table I face towards the cockpit, and there we have enough windows/doors made from polycarbonate. Rigging, you are a great advocate of junk rigs (I belief you are the person who was looking for a junkrig solution for a Searunner, perhaps I am amiss). I like junkrigs to. But as from others mentioned, there windward performance is so la.la as we say in France. Besides the are very complicated (see the latest from Pete) with a lot of ropes everywhere. Only for this reason, the airstream will be disturped. Before the wind til 45 degree the are great. Now comes the point, the KD 860 is not slow so the apparent wind will move forward and you sail almost alwise on the wind. The weak point of the junk rig. Pete reached with the ORYX 14 knots, but for passages he slowed her down to 7 knots. Of course, then it works.See by the way the picture from his new rig. In the photo series is a photo from a friends junk with a semi wing sail he made for 50.000 pesetas. This sails here working great. This was an phantastic solution. This was around 1969. He could set the sails by hand, the floated more or less up. His halyard winch was green, because he never needed the thing. A tip no big watertanks, use a watermaker. We had an electric SURVIVOR. 12V, 5 Amps 10 liter water. We had a windgenerator and two very good solar panels. Was good for all the electrics, navvy lights, waterpomp etc. Engine, use a longtail drive with a penger in the mast beam with a Lewis surface piersing prop (the have props for low speed by the way) The produce now under an other name, because my friend Lewis is deat for some years, but you find them in the Internet. By the way you find here also a solution for looking forwards. See album 860Fi.? I was now writing how it was coming in my mind. I know there are many English mistakes in, but I hope you get my gist and I am not in the mood to correct, sorry about that. At last, I do now somethin I never did before, here a rendering from a new design, a German customer called it a "Bohrinsel". Be assured the KD 860 will sail better as this thing.
Cheers
Bernd
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Hi. the boat was designed to be offshore capable and Is I'm my opinion. However a catamaran of this size is on the cusp of what you can get away with for extended cruising and live aboard use. I Think Richard woods intimates this for his cruising designs in the 8 -9m size as well. The problem with catamarans is, you have all the space in the world to put stuff, but not the ability to cary it (safely). As opposed to a monohull, where it will take the weight but no space to put it. Having 2 hulls (that are slender enough to perform as a sailing boat) does not add up to great payload capacity Plenty of people put all there cruising gear in small catamarans, but look were the water line ends up. On pictures of Oryx the water line is well above the transoms. The designed fully loaded waterline is supposed to be with the transoms just clear of the water for the KD860. You can pile as much stuff as you like into a small catamaran and it won't sink, but will it still be sea worthy? When you add up the weight of all the gear that you would take for long term cruising, it becomes significant. for example.- Main anchor and rode, spare anchor and rode, fenders and fender boards, shore lines, engine spares, boat repair spares, safety gear, sufficient battery capacity and charging ability to run an autopilot 24h/day, dingy and oars, fuel , water, food, people, peoples clothes and personal items, nav charts and books guides etc, rigging spares, spare autopilot or parts, droge and or sea anchor + warps, stuff to cook on and eat off, first aid gear. And it just goes on and on. So the simple thing to do, is do a calculation on your expected payload that you require, and get a boat designed to carry it, the Kd860 may or may not be the boat for your application. In my situation, I wanted the smallest boat that I could , single hand, do extended coastal cruising, do occasional?offshore passages, afford to build and maintain. And in that respect the KD860 is perfect. For living aboard as a couple and long term cruising on a budget, I think the voyager design would be the choice.? Cheers…... Andrew.
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> Distance waterline bridge deck as shown 600 and 700mm from the cockpit.
It isn't right. At KD860 project it's 500 and 600mm
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Hi Andrew
?Thanks for your throughts about the KD 860 after your very negative end statement of your last letter. Multihulls are load sensitive of course, because ascelleration in a squall is there only devence. The KD 860 is here no exeption. But the boat is extreme stable by design. See the dynamic stability calculation which is extrem conservative. Because I calculate with a safety factor of + 90%!!!!! I add the dynamic stability diagram. When you look at this interesting facts are obviouse. The maximum rigthing moment is 5400kg with the sail area of 37m2. At an angle of 55 degree(windforce 30 knots full sail) ?there is a recovery hump with an righting moment of still 1300kg, which gives you time to release the mainsheet and bear away. As a small reminder, never luff a multihull in such an situation, the rotational added moment ( weigth of the rigg) would turm the boat over. Nobody in his right mind would sail in a wind of 30 knots with full sail, also a small sail as this of the KD 870. It is per design no racing boat. This is reflected as you observed with the low apect ratio of the hulls which is in this case 1 : 8. Normally I design not under 1 : 12. Here we have also the reason the boat has a good load factor. Which makes the boat cabable for longer yournay.? About 17 % of my clients are members of these group. Logical it is an English language group. I have clients in Swasiland the can read drawings but not the language. My Japanese friends have the same problem. 7? KD 860 are used as life on board boats because of the relative high load factor.. Some solo, others as couble, All of them made long passages without any problem. Two are now sailing around the world. I get sometimes a letter, because the are not interested in the Internet, the are happy to be away from just this part of or sillivication (no mistake). Speed, as mentioned it is no racer, the report etmals of 180 to 200 miles. This is a medium speed of 7 knots. Our Pelican was very fast and 16 knots was not unusual. But lucky we have a brake on multis, shorten sail. Above 11 knots any cutlery starts to rattle. When I, or my wife where cooking, we slowed the boat alwise down. In conversations with other sailes, the where done the same. A time ago I was reading an article in french "Multoque". The where sailing a "Tectron" from Canada to France. When cooking the did the same. Racing is a differnt story, I know in the days of the first multihull races. The had a lot of cakes on board for food. Nothing to cook and sufficient calories for the hard work. I will go into the load capacity and what to have on boart (anchor etc) in my answer to H.M. Thanks for your througths, which is at least more, as your statement in your last letter that the KD 860 is not suitable.
Bernd ?
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right, anyway with a load factor of 1 : 2 it is more as okay as customers who made and make ocean passages reported to me
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Andrew:
??? This is exactly the problem I'm wrestling with.?? Multihulls
have limited load carrying capacity, and as Bernd mentioned I've
been looking at some of Jim Brown's Searunners, and to get the
same payload means going with the 37 footer........ that's a BIG
boat.?? The problem of course is what constitutes "payload" and
"dry weight" is something I believe varies significantly from
designer to designer, and as Bernd pointed out, it's easy to over
build, and people have a tendency to doll boats up with pretty
stuff that is not particularly valuable, but adds to weight.?? I
am beginning to realize that virtually all small multihulls are
overloaded when making passages.?
??? The only way I can see to judge real world weight and payload
for an individual boat meaningfully, would be to have the boat
sitting in the water as equipped..... rig, anchors and rode, and
other known items, then load it using plastic drums of water or
sand bags, etc until it was sitting at LWL.?? This would give a
real world working payload...... each drum of water would work out
to about 215 kg, and they could be properly distributed and filled
using a pump and siphoned out.??? I consider something like this a
reasonable first step before even doing a survey.? Can it
realistically do what I want to do is the first question.??
??? I'm mostly a single hander....... it's my nature, I enjoy
solitude, however it's only logical on a long passage, say the
Canaries to Barbados, or Panama to the Pacific Islands to take on
a crew member.? That alone adds up to about 250 lbs of human flesh
and gear, plus 4.2 pounds of water per day, and probably 3 pounds
of food....... Let's say 500 total additional pounds for a
crossing including a safety margin.??? As Bernd points out a
watermaker makes sense when looking at 250 pounds of water plus
containers..... a human powered water maker would be great.... You
want a fresh water shower... start pedaling!?? A water maker also
makes it possible to reduce the weight of food stores.?? Things
like beans, rice, noodles, dried foods, etc, all require water to
prepare, and are all light weight high energy foods.?? You can
only reduce spares by having fewer systems / simpler systems.? The
junk rig with it's free standing mast(s) eliminates all standing
rigging.? It doesn't require winches, or a mast with a track and
slides, it doesn't require a traveler or a vang, and it only has a
single sail per mast.? Tacking is almost a simple as making a lane
change in your car.? You can reef with a cup of coffee in one hand
without spilling it.? Blondie Hassler crossed the Atlantic in
Jester wearing bedroom slippers...... or so he claimed.??? In my
book, simple is best, even if it means sacrificing a bit of
convenience, and speed.??? Simpler ultimately ends up being
lighter in most cases.?? How much stuff can I NOT have??? Pumped
water and flush toilets are at the top of the list to eliminate.??
A plastic jug with a spigot on a shelf is "running water".?? A
black plastic bag hanging in the sun.... solar shower / water
heater.??? Propane bottles weigh nearly as much as the fuel in
them, and are an absurd cooking fuel for a light weight boat.??
I've seen photos of big heavy wooden tables in the saloon on these
boats........? absurd dead weight that takes displaces payload.??
Looking at the interior photos of cats, one sees all kinds places
where weight could be removed or reduced.??
????????????????????????????????????????????????????????????????????????????????????
H.W.
On 11/23/2017 05:16 PM, andrewklees@... [k-designs]
wrote:
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Show quoted text
?
Hi. the boat was designed to be offshore capable and Is
I'm my opinion. However a catamaran of this size is on the
cusp of what you can get away with for extended cruising
and live aboard use. I Think Richard woods intimates this
for his cruising designs in the 8 -9m size as well.
The problem with catamarans is, you have all the space
in the world to put stuff, but not the ability to cary it
(safely). As opposed to a monohull, where it will take the
weight but no space to put it. Having 2 hulls (that are
slender enough to perform as a sailing boat) does not add
up to great payload capacity
Plenty of people put all there cruising gear in small
catamarans, but look were the water line ends up. On
pictures of Oryx the water line is well above the
transoms. The designed fully loaded waterline is supposed
to be with the transoms just clear of the water for the
KD860. You can pile as much stuff as you like into a small
catamaran and it won't sink, but will it still be sea
worthy?
When you add up the weight of all the gear that you
would take for long
term cruising, it becomes significant.
for example.-
Main anchor and rode, spare anchor and rode, fenders
and fender boards, shore lines, engine spares, boat repair
spares, safety gear, sufficient battery capacity and
charging ability to run an autopilot 24h/day, dingy and
oars, fuel , water, food, people, peoples clothes and
personal items, nav charts and books guides etc, rigging
spares, spare autopilot or parts, droge and or sea anchor
+ warps, stuff to cook on and eat off, first aid gear. And
it just goes on and on.
So the simple thing to do, is do a calculation on your
expected payload that you require, and get a boat designed
to carry it, the Kd860 may or may not be the boat for your
application.
In my situation, I wanted the smallest boat that I
could , single hand, do extended coastal cruising, do occasional?offshore
passages, afford to build and maintain. And in that
respect the KD860 is perfect. For living aboard as a
couple and long term cruising on a budget, I think the
voyager design would be the choice.?
Cheers…... Andrew.
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Bernd:
??? I'm not at all what this is intended to mean..........
On 11/24/2017 05:44 AM, Bernd@... [k-designs] wrote:
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?
right, anyway with a load factor of 1 : 2 it is more as
okay as customers who made and make ocean passages
reported to me
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Hi? as a small multihull sailor (Duo480 Jigsaw) I am all too well of the drop in performance of a multihull when it is loaded up with extras. However I just day sail mostly, and yet carrying a motor, anchors, chain, cooler bins, makes a huge difference to the performance.?
I believe this was Andrew's main point. The KD860 itself is more than capable of sailing off shore, but when you add in the weight of the extra equipment and supplies needed for extended off shore cruising then the weight limits are reached very quickly. This is the heart of the matter and the design is irrelevant . For a multihull, a boat of less than 9 metres is just too small to carry the load efficiently, and it doesnt matter who the designer is. That is my very firm belief.
I am a great fan of the KD860, and if I were to build a bigger boat this would be the one. But I would not plan on sailing it from here in New Zealand to Hawaii or anything like that, for the above reasons. As for the other factors mentioned, eg sails: I dont understand junk rigs so I would never choose them. Our local harbour has a very strong tidal movement so I would consider a dagger board instead of the AV panels.
Actually, as I have found with the Duo 480, and also the KD650 on which I have sailed often, the asymmetric hulls work really well, and so I would suggest to you why not go for the Voyager, and then your concerns about off shore capability would be not a factor.
regards ?Bryan
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Brian:
??? I will agree that the 860 is on the minimal side, but I'm not
a family man, and sail single handed normally.? The voyager is
absurdly huge for my needs.? My direction is less rather than
more, which perhaps is a mistake..... but it is my normal mode of
existence.?? I live "small" because I live "out of a house", not
"in a house"...... does that make any sense???? My entire thrust
is toward smaller and simpler, and lighter.? It all points to less
cost at every level, and my budget is limited, and what I have I
want to spend cruising, not on up front costs or continued
maintenance costs.???
??? The 860 appeals to me in many ways.? I feel Bernd made all the
right choices, though the scale is just a tad small.?? The 980
variant, which he does not offer as a plans set, or Pete's 10
meter variant, just about nail it for me.?? I don't want a 40'
boat.???
??? In "real life", we must compromise....... we can't have
everything we want....... I don't live in the "big rock candy
mountain" fantasy land with the lemonade springs and the cigarette
trees, and the little streams of alcohol trickling down the rock,
where the sun shines every day and the bluebird sings....
etc.........????
??? The reality is that what works for me, probably will not work
for you, and vice versa, we have different priorities.? What I do
NOT want is to be pushed into a bigger and bigger boat.?? It's
been said again and again..... and it is right.........?? The
biggest mistake people make is to buy too big a boat, the second
biggest mistake is to buy to small a boat......for their
needs.???? In the multihull world, I'm seeking the "right"
boat....... it isn't a 40 footer.
??? Talk is cheap, so they say..... In all likelyhood, I'll never
own one of Bernd's designs, as much as I admire his work.?? I
don't plan to build a boat on that scale........ I'm currently
building my fourth small boat, and plan to build number 5 not long
after..... a simple stitch and glue dinghy.?? I'd lay down the
cash and sail Oryx away in a heartbeat, if it wouldn't wipe out
most of my cruising budget... Pete has it for sale.?? I'm a "penny
ante" player, not a high roller.?? Everything about the 860
appeals to me, except that the size is just a tad small.
??? Pete Hill of course brought Bernd's designs to my attention
with Oryx.? I've followed Pete, Annie, and Carly since the days of
Badger..... before that I had dismissed small cats as completely
impractical, though a few designers like Richard Woods, and Roger
Simpson, were at least interesting.?? I never fell under the spell
of Warram, but living in a temperate climate that should be
understandable.
??? It's obviously a tough business.... when you go really large,
things start to work well on a cat.? I don't need or want a "condo
cat".???? There really is no "free lunch" here.
????????????????????????????????????????????????????? H.W.
On 11/24/2017 10:11 AM, bryanandmarycox@... [k-designs]
wrote:
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?
Hi?
as a small multihull sailor (Duo480 Jigsaw) I am all
too well of the drop in performance of a multihull when it
is loaded up with extras. However I just day sail mostly,
and yet carrying a motor, anchors, chain, cooler bins,
makes a huge difference to the performance.?
I believe this was Andrew's main point. The KD860
itself is more than capable of sailing off shore, but when
you add in the weight of the extra equipment and supplies
needed for extended off shore cruising then the weight
limits are reached very quickly. This is the heart of the
matter and the design is irrelevant . For a multihull, a
boat of less than 9 metres is just too small to carry the
load efficiently, and it doesnt matter who the designer
is. That is my very firm belief.
I am a great fan of the KD860, and if I were to build a
bigger boat this would be the one. But I would not plan on
sailing it from here in New Zealand to Hawaii or anything
like that, for the above reasons. As for the other factors
mentioned, eg sails: I dont understand junk rigs so I
would never choose them. Our local harbour has a very
strong tidal movement so I would consider a dagger board
instead of the AV panels.
Actually, as I have found with the Duo 480, and also
the KD650 on which I have sailed often, the asymmetric
hulls work really well, and so I would suggest to you why
not go for the Voyager, and then your concerns about off
shore capability would be not a factor.
regards
?Bryan
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I would like to make a few points about using the 860 for ocean cruising. I think the 850 is a nice small cruising catamaran for crew with
discipline to not overload. However, it's size limits capsize resistance
in big breaking waves, limiting the passages to places with reasonable?
waves.
Weight capacity is adequate if the crew is disciplined about what they bring. Many cruising crew are not disciplined enough for even much larger catamarans. Because the 860 is so small, it puts a premium on this skill. Sit down and make a careful weight study of what you need. It only takes a few hours. If you still have reasonable reserve capacity, you should be OK as long as you don't become a pack-rat. For my own boat, I remove everything not screwed down once each year, clean the inside of the boat with bleach solution and then only restow what is truly needed. Over the years I have had very little increase in variable load.
Size affects the seaworthiness of multihulls. Any skilled sailor can reef early to prevent capsize from wind. However, smaller multihulls are more sensitive to big waves. I have never capsized a catamaran in big waves and I have sailed in 50-knot winds, gusting much higher, and 25+ feet breaking waves. The point is that the crew has less control over capsize when the waves get really large and steep. When the face of a breaking wave jets against a hull it can impart tremendous energy that tries to capsize the boat. This force is resisted by the hull slipping and its mass moment of inertia. So large catamarans can withstand much bigger waves because they have a much bigger moment of inertia.
In Practical terms this means that where you sail effects the safety from capsize due to waves. Some parts of the world are very difficult. For example the area between Hawaii and the Philippians has over 40-ft breaking waves during typhoons, there is no safe season and distances are vast so that a clear weather window can be too short for a crossing. I think larger multihulls are much safer in areas like this. However, most of the worlds oceans are not as difficult and smaller boats are a better fit.
|
Hello Mr. H.&.M. and other contributors to this issue
Here
we go again. I belief have read my answer to Andrew. Which answers
also some of your questions in this letter.
Coming
first back to weights. The rig as shown will weight in including
sails and rigging 135 kg (Dynema stays). My wishbone gaff rig
weights about 145 kg. This extra weight is in the furler on the
yackstay and the wishbone. We used a similar rig later on our
Pelican. Unfurling the sail about 10 seconds, furling the sail about
20 seconds including setting the inducing setting of the topping
lift.. You can not do it faster with a junk rig. Windward angle
without pinching but some speed decrease 35 degree, optimum with
better speed 40 degree.
By
the way, you need only Aluminum tubes for the mast, which is a big
money saver. The wishbone is a material mix from stainless steel and
Aluminum. When you can weld stainless steel then it is good to do.
When I look at most of the junk rig with all the ropes I have some
taut about running resistance and the mast on the wrong side. If I
would use a junk rig then the simple Jester rig. When you look for
instance on all the different sail and other modification at many of
the junk rigs including the extreme low aspect ratio junk rig on the
ORYX with all the experience Peter has starting with the "Batcher"
I see no reason to use it. This includes the Tyler Aerorig. When I
calculate the time to build all the wishbones it would be a no-no
for my. I am not this patient. Costs is an other factor. Besides a
simple junk rig like on the Jester the are more expensive as any
sloop rig. But at the end it is up to you. The only cheap and good
working wing sail junk was the boat of my friend I was showing the
photo yesterday. The only two photos I have are also in the photo
folder. The boat was so easy to handle that his engine was a big
junk of roost. One day he sailed into the old Denia port at wind
force 7 to 8. His cockpit still closed. At the last moment he opened
the cockpit rounded of to his his mooring and let down the rest of
his sails. He was not a special kind person, but a gifted designer
builder and sailor. He was known on the coast as "Ken on the
rocks". A pity, I made only some sketches of his super simple
wing rips which I lost somehow. General, the forward part was a wing
section with a big flap. So far to the rig. ?So far to the rig.
By the way this is not means to convert you. So to see you are a
junk addict and why not. This was long, next only short answers.
Coming
back to weight. First a strange thing, catamarans need more heavy
ground tackles. For this boat say a Bruce anchor of 20 lb (10kg)and
a 3/5 chain, length 60ft 24 kg. Rope 14mm 100m 18 kg. Also together
52kg The second anchor gear 2/3 also 34 kg together 86 kg.
Rigging
my Wishbone rig mast AL tubes different diameters 140mm lower part
130mm upper part 57 kg + Wishbone gaff complete 6 kg. Furler without
profile 6 kg weight total 95 kg (compare to junk rig, significantly
less). Water 80litres. Katadyne 35 electric 15 kg. Fenders and other
deck gear 28 kg. Engine 56kg. Solar panels+ wind generator Rutland
40 kg. Batteries (up to you if you use lithium of sufficient
capacity about 18 kg)
Total
with some tolerances 392 kg. Boat weight complete incl water = 1795
kg. Useful extra load till waterline
=
1058 kg. Minus the dinghy of course, but I am sure sufficient for
food, clothing, navigation tools chard's books canary etc. will be
sufficient for a route of 4000 mile at a speed of 6 knots = etmal
144 miles = 27,77 days.
With
good planning the probability to run in a severe storm is 7% at the
normal routes around the usual banana belt. When you sail outside
this area the storm probability is 8%, These are meteorological data
from the NOAA. For
a good information of the weather conditions everywhere on the world
is this link very helpful
Now
again and at last. There where many trips made around the world with
small catamarans (or monos). But lets stay with the catamarans. Go to
the web pages of Emmnuel an Maximilien Berque. The where sailing the
Atlantic with a 6m Proa and a 6m catamaran. By the way with the proa
without sextant and chards. It is an attitude. For all the other
arguments from distriputors to this thema, many thanks. All are right
in there views, but it must not be my view or from others. In any
case interesting. One needs a palay an other only a tent.
At
last to this issue, good seamanship is the crucial factor, you can
loosen your boat more easy on a coast as on the sea. Per my own
mistake we where in a winter mistral (December 1990) 8 miles out the
coast. Not far, but it was more safe to went out to the sea. Winter
mistrals are more sever (about force 10 with a temperature of 8
degree, also very tense air). No problem, we streamed in a bend 160m
16mm rope out with a tire. 4m2 storm jib, Full control over the boat
all the time. It was so easy that my wife was even cooking (by the
way, cooking would be impossible on a mono).
Short
back to the KD 860. The plans now sold for many years and I picked up
some ideas which I have adapted in the plans, like the forward
windows, a center/dagger board which folds completely back and can
not damage the boat and the Whisbone rig (not included in the
standard plans set, but can be separate ordered). I think this is
sufficient to close the discussion regarding this issue. ? Bernd?
|
Thanks Bernd:
??? This is a far more comprehensive response than I had really
expected, and addresses all my questions on the topic.? Not much
more to say or ask on the topic of weight.??? This really isn't
the place to get into the? merits and liabilities of junk rigs.??
The junk rig association (JRA) and the Yahoo forum on junk rigs,
are both great resources, and all of the issues you have brought
up have been discussed ad infinitum, as well as soft wing sails.??
??? I appreciate the time you have taken to clarify this payload
question, and hope that it is of as much interest and value to
others as to me.
??????????????????????????????????????????????????????????????????????????????
H.W.
On 11/25/2017 08:19 AM, Bernd@... [k-designs] wrote:
toggle quoted message
Show quoted text
?
Hello Mr. H.&.M. and other contributors to this issue
Here
we go again. I belief have read my answer to
Andrew. Which answers
also some of your questions in this letter.
Coming
first back to weights. The rig as shown will
weight in including sails and rigging 135 kg
(Dynema stays). My wishbone gaff rig weights
about 145 kg. This extra weight is in the
furler on the yackstay and the wishbone. We
used a similar rig later on our Pelican.
Unfurling the sail about 10 seconds, furling
the sail about 20 seconds including setting
the inducing setting of the topping lift.. You
can not do it faster with a junk rig. Windward
angle without pinching but some speed decrease
35 degree, optimum with better speed 40
degree.
By
the way, you need only Aluminum tubes for the
mast, which is a big money saver. The wishbone
is a material mix from stainless steel and
Aluminum. When you can weld stainless steel
then it is good to do. When I look at most of
the junk rig with all the ropes I have some
taut about running resistance and the mast on
the wrong side. If I would use a junk rig then
the simple Jester rig. When you look for
instance on all the different sail and other
modification at many of the junk rigs
including the extreme low aspect ratio junk
rig on the ORYX with all the experience Peter
has starting with the "Batcher" I see no
reason to use it. This includes the Tyler
Aerorig. When I calculate the time to build
all the wishbones it would be a no-no for my.
I am not this patient. Costs is an other
factor. Besides a simple junk rig like on the
Jester the are more expensive as any sloop
rig. But at the end it is up to you. The only
cheap and good working wing sail junk was the
boat of my friend I was showing the photo
yesterday. The only two photos I have are also
in the photo folder. The boat was so easy to
handle that his engine was a big junk of
roost. One day he sailed into the old Denia
port at wind force 7 to 8. His cockpit still
closed. At the last moment he opened the
cockpit rounded of to his his mooring and let
down the rest of his sails. He was not a
special kind person, but a gifted designer
builder and sailor. He was known on the coast
as "Ken on the rocks". A pity, I made only
some sketches of his super simple wing rips
which I lost somehow. General, the forward
part was a wing section with a big flap. So
far to the rig. ?So far to the rig. By the way
this is not means to convert you. So to see
you are a junk addict and why not. This was
long, next only short answers.
Coming
back to weight. First a strange thing,
catamarans need more heavy ground tackles. For
this boat say a Bruce anchor of 20 lb
(10kg)and a 3/5 chain, length 60ft 24 kg. Rope
14mm 100m 18 kg. Also together 52kg The second
anchor gear 2/3 also 34 kg together 86 kg.
Rigging
my Wishbone rig mast AL tubes different
diameters 140mm lower part 130mm upper part 57
kg + Wishbone gaff complete 6 kg. Furler
without profile 6 kg weight total 95 kg
(compare to junk rig, significantly less).
Water 80litres. Katadyne 35 electric 15 kg.
Fenders and other deck gear 28 kg. Engine
56kg. Solar panels+ wind generator Rutland 40
kg. Batteries (up to you if you use lithium of
sufficient capacity about 18 kg)
Total
with some tolerances 392 kg. Boat weight
complete incl water = 1795 kg. Useful extra
load till waterline
=
1058 kg. Minus the dinghy of course, but I am
sure sufficient for food, clothing, navigation
tools chard's books canary etc. will be
sufficient for a route of 4000 mile at a speed
of 6 knots = etmal 144 miles = 27,77 days.
With
good planning the probability to run in a severe
storm is 7% at the
normal routes around the usual banana belt. When you
sail outside
this area the storm probability is 8%, These are
meteorological data
from the NOAA. For
a good information of the weather conditions
everywhere on the world
is this link very helpful
Now
again and at last. There where many trips made
around the world with
small catamarans (or monos). But lets stay with the
catamarans. Go to
the web pages of Emmnuel an Maximilien Berque. The
where sailing the
Atlantic with a 6m Proa and a 6m catamaran. By the
way with the proa
without sextant and chards. It is an attitude. For
all the other
arguments from distriputors to this thema, many
thanks. All are right
in there views, but it must not be my view or from
others. In any
case interesting. One needs a palay an other only a
tent.
At
last to this issue, good seamanship is the crucial
factor, you can
loosen your boat more easy on a coast as on the sea.
Per my own
mistake we where in a winter mistral (December 1990)
8 miles out the
coast. Not far, but it was more safe to went out to
the sea. Winter
mistrals are more sever (about force 10 with a
temperature of 8
degree, also very tense air). No problem, we
streamed in a bend 160m
16mm rope out with a tire. 4m2 storm jib, Full
control over the boat all the time. It was so easy
that my wife was even cooking (by the
way, cooking would be impossible on a mono).
Short
back to the KD 860. The plans now sold for many
years and I picked up
some ideas which I have adapted in the plans, like
the forward
windows, a center/dagger board which folds
completely back and can
not damage the boat and the Whisbone rig (not
included in the
standard plans set, but can be separate ordered). I
think this is
sufficient to close the discussion regarding this
issue.
?
Bernd?
|
Size doesn't always matter in my opinion. Here is a great story from years ago about a boat that was barely 6 meters... of course there are few comforts. :)
|
?You are rigth, it was not necessary to go into the junk rig details. I am also a memberfrom the Junk Rig Assication. Because there are intersting developments. I like special some of the Norwegian boats with there beautiful champerd sails. I hope also that the discussion was, besides for you, helpful. Thanks for all the contriputions from the others. At last here two pictures from complete different rigs to make my point in this respect.?
Cheers
Bernd
|
John:
??? Thanks:
??? ??? Where are the other 7 parts of the story to be found??? I
like New Zealand, if one has to choose a place to be
"stranded".................
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? H.W.
On 11/26/2017 01:47 AM, John Cudak cudak62@... [k-designs]
wrote:
toggle quoted message
Show quoted text
?
Size doesn't always matter in my opinion.
Here is a great story from years ago about a boat that was
barely 6 meters... of course there are few comforts. :)
|
Yep 500 & 600mm is correct for bridge deck clearance for kd860. And hull width to lenght ratio @ waterline is 11:1 not 8:1 as far as i know.
|
Bernd Kohler