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Nordic cat · 26-02-2008, 06:28

Quote:

Originally Posted by Manie B

Gentlemen please help and give an opinion of this cat for world cruising. I have searched far and wide and i believe it is a great design. This thread has truly been a huge help. I am able to build this cat in South Africa at approx. 120 000 US dollar. It means to me a new boat (built to designers specs) with new fittings and that i dont have to worry about the unknown aspects of a used / abused boat.

The idea is not to have a floating palace - but a reasonable boat - well finished - that will be safe in moderate climates / weather and that could handle the unforseen storm.

Looks like a good design from a designer who has proved that he knows a thing or 2 about designing cats.

The payload stated is on the low side if you want to go world cruising, just confirm that it is only 900 kgs. Even with a waterrmaker, just watermaker and 100 litres reserve takes 150kgs. 4 people including their stuff is 500kgs. This leaves 250kgs for provisons, extra rope, anchors, dinghy etc. Not much.

You will probaly need a bigger battery bank than standard for long term cruising, autopilot, comms equipment, safety equipment etc.

I reckon minimum payload needs to be double, i.e. 1800 kgs minimum.

Bridgedeck clearance is a bit low for your part of the world, but could probably easily be increased up to around the 80 cm mark at midships, for a bit more windage.

I would prefer dual engines, regardless of what type, to get the manoueverability in tight places.

The 120,000 USD sounds low, just the rig and sails are probably 20 k.

This is without the 2500-3000 hours needed to get a nice finish as you say?

I would choose a longer boat if possible, without increasing the inside storage.

Have you looked at some of the Australian designers like Bob Oram? Also one or 2 who do good plywood designs.

Good luck with your project and let us know what you decide on.

Regards

Alan

Gambler · 27-02-2008, 01:19

Hi Andreas,

We are almost in the same position and phase as you, i.e. searching for a cat to be used for one year at sea with start from a Nordic country. In our case Sweden. I have followed your intersting threads and comments, and do recognize the concerns about which boat to choose. We also share most of the required characteristics on your list. Being a "monohuller" for all my life, the catamaran addiction is quite a new thing, and so far I have only sailed two cats; Nautitech 40 and Dean 440 Aero. Both for one week.

Since I have followed your "debate" on this forum, I have noticed that the one "really don't want" on your list, now is a feature on at least one of your favourites. Revalued, and what is the reason? Would be interesting to know.

Further, since we seem to have the same prerequisites, I would like to know why the Dean fell of from your list? The Dean is on our short list and I would like to know if there is a reason to revaluate?

The cats on our list for to day are:

Dean 440 Aero
Dean 40
Outremer 45 - 50
Catana 411
Catana 44
St Francis 44 Mk II
Leopard 45
Kronos 45

And yes, we are looking for a used one. Let say absolute max 15 years old, but preferebly around 5 years old, and within a budget range of € 250 k.

Are you going to start your trip from Norway?

//Zoltan

**Alan Wheeler** · 27-02-2008, 10:37

May I just remind members that Vendors can not publish prices/quotes etc here on the regular threads. They can only do so in the Vendors Forum. So if anyone is specificly wanting to ask a vendor a price, you need to invite them to that Forum heading and are then most welcome to talk dollar to their hearts content.

Also, if anyone is wanting to talk buying or selling, may I also remind members that the Classifieds is the correct forum to post in for this.
This is just a reminder, not suggesting rules have been broken. It just helps to stop these threads becoming cluttered with noise making the actualy topic difficult to see.

BigCat · 27-02-2008, 13:41

"I suspect that the existence of rocker on most offshore cruising cats was specified as a compromise between reduced pounding/reduced drag through an elevated transom, and an increased tendancy to hobbyhorse."***** ***** ***** ***** *****Hobbyhorsing is caused by the relationship between the bow and the stern shapes, not by a relationship between either end and the middle, so rocker is irrelevant. I suspect that people who believe that rocker is related to hobbyhorsing are making an analogy between a rocking chair and hull rocker, but hull rocker is all under water, at least in a cruising boat, and the analogy is false. For rocker to cause hobbyhorsing, most of the hull would have to be out of the water, as in a lightly loaded dory. A full bow mated to a fine stern will cause hobbyhorsing, as the bow provides a lot of lifting force, and the fine stern is poor at dampening the resulting pitching. To have less rocker with a given displacement you have to do one of 3 things-make the hull very narrow at the waterline, or give a deep forefoot and a deep stern (feasible only with a double-ended type hull,) or make the boat very narrow. Harry Proas have little rocker because they are ultra-light for their length, and so have little displacement needing to be accounted for in the underwater volume. As I keep saying, hull rocker is a function of volume, which equals displacement, once the type of hull has been determined. Because they had narrow waterlines, constant camber type designs had more rocker than is usual today. Modern catamaran hull shapes are typically more like monohull shapes than they used to be. Almost all designers now use a hull form with medium to large beam at the waterline, sharp forward, rounded amidships, and flattened aft. Departures from this shape today are usually compromises with a desire to make hulls out of plywood or other sheet materials, resulting in deep "v" shapes, or flat bottomed shapes. Designers seeking speed keep the waterline beam moderate, and those seeking a spacious interior or a large displacement on a shortish length use larger waterline beams.

44'cruisingcat · 27-02-2008, 15:10

So in your opinion (and opinion is what it is) the underwater shape of a boat doesn't effect how much it will pitch, as much as the above water shape does? Interesting theory.

Robertcateran · 27-02-2008, 15:59

In as much as when the underwater sections stay underwater, I have to agree, that the underwater shape does not contribute to hobbyhorsing, but if the bow depresses, then the stern will lift more readily with more bouyancy in the middle, the rocking can start to begin and the rocker can influence. Flared bows are probably the worst causes for hobbyhorsing, especially with an underwater shape that doesn't damp the movement.
Robert

BigCat · 27-02-2008, 16:15

Well, pitching is controlled by the shape at the ends, at any rate, including any overhangs that there may be, down low enough to encounter the water as waves pass. Fuller ends don't plunge as far as narrower ones, because they have more volume, and more quickly immerse the volume necessary to counteract the pitching moment. ***** ***** ***** ***** This idea is not original to me. I think that the location of weights fore and aft is relevant, but that it interacts with the shapes of the ends such that the finer your bow and stern, the more concentrated amidships your weights need to be. John Shuttleworth thinks rocker and "symmetry" of hulls contribute to pitching, but I don't see any way for rocker to come into the matter, since the volume in the center is under water the whole time. Essentially, Shuttleworth described old-fashioned multihulls, and pointed out that they tended to pitch. Here is an interesting article on catamaran design: Cruising World - Join the Cat Crowd

Robertcateran · 27-02-2008, 17:28

We seem to be coming to close to consensus, though I can see John Shuttleworths point of symmetry being a factor, due to hydrodynamic effects.
About rocker, taking an extreme case of two boats with the same prismatic coefficients and similar bow and stern shapes, one with a near flat bottom and pretty fat amidships, and the other skinny in the middle but fairly deep. The hydrodynamic resistance to hobbyhorsing would be less in the one with more rocker. The modern multihull is flat enough to provide decent hydrodynamic damping with its under water profile.
The Harry manages the high prismatic coefficient by allowing the ends to remain under water as it doesn't have to tack. The reduction in drag for the transom is by having a skinny end- Not optimal, but a fair compromise. The light weight certainly doesn't hurt, and this is accomplished by the low sailing stresses of the design, and is integral to the design,
Robert

BigCat · 27-02-2008, 18:10

Hydrodynamic effects usually refers to things like planing hulls or hydrofoils, where the forward velocity is pushing against a flat surface to provide lift, essentially like skipping a stone on the water. I don't think the concept applies here at all. A Harryproa is hard to relate to a discussion of catamaran pitching because it has two very different hulls. Being so different, they would probably tend towards less pitching because they are impacting a waves lifting effect at different times. The two hulls are probably very different in another way as well, in that the long hull is very much lighter than the short one, which contains the accommodations. I see no possibility of 2 hulls being similar in the ends but very different in the middle, unless one of these boats were to be very unfair, which would introduce its own problems. I'm not sure what you mean by prismatic coeffecient being in and out of the water, as the concept refers only to the part of the boat that is normally under water, being a measure of the fineness of the ends underwater as compared to the middle underwater when the boat is at rest in calm water.

JamuJoe · 28-02-2008, 07:19

Kapena, I own a Leopard 42 (Robertson & Caine, Capetown) and find you misinformed on a number of points. I'll agree that the relatively low bridge deck clearance is a fact, and she does feel some slap beating into seas over 3 feet. Otherwise, there is easy access with handholds to ample side decks for my size 12 feet, a full clear transom, stout dingy davits, ample bow bouyancy, and the berths (walk around in the forward cabins) have no shelves at the edge of the mattress. Helm has a brake, full engine access under aft berths, huge cockpit and the large fixed table takes up less than 50% of the huge cockpit. We've sailed JAMU extensively in all weather, and she has held up very well in charter service for 4 years. Just my opinions (and actual experience).

Robertcateran · 28-02-2008, 23:27

Reply to Big Cat. Hydrodynamics is the physics of movement of water. A boat at rest in the forward direction, but rocking backwards and forwards has parts of the boat moving relative to the water and thus moving water. The tendency to rock can be reduced by putting flat plates on the end. This is often done for wharrams and some other boats with this tendency. A flatter boat will have more resistance to rocking backwards and forwards than a boat with a deeper section.
I am well aware of what prismatic coefficient mean (hydrodynamics was part of my maths degree). Yes it does refer to the hull shape that is in the water at rest, but one needs to consider the effect of the boat when the bow is depressed under load.
Robert

Therapy · 29-02-2008, 10:08

Quote:

Originally Posted by Robertcateran

Reply to Big Cat. Hydrodynamics is the physics of movement of water. A boat at rest in the forward direction, but rocking backwards and forwards has parts of the boat moving relative to the water and thus moving water. The tendency to rock can be reduced by putting flat plates on the end. This is often done for wharrams and some other boats with this tendency. A flatter boat will have more resistance to rocking backwards and forwards than a boat with a deeper section.
I am well aware of what prismatic coefficient mean (hydrodynamics was part of my maths degree). Yes it does refer to the hull shape that is in the water at rest, but one needs to consider the effect of the boat when the bow is depressed under load.
Robert

Righto!
I want to know what happens when things are-a-happinin!!!

Stella Polaris · 29-02-2008, 23:38

Hi Zoltan,

It's always nice to hear from a fellow Scandinavian.

Quote:

Originally Posted by Gambler

Since I have followed your "debate" on this forum, I have noticed that the one "really don't want" on your list, now is a feature on at least one of your favourites. Revalued, and what is the reason? Would be interesting to know.

Are you talking about daggerboards? … If so, then yes, I have changed my mind about them. For a few different reasons:
1. Daggerboard cats point higher than non-daggerboard cats.
2. Daggerboard cats tend to have much lower draft (this is good not only when heading into shallow anchorages, but also when you’re stuck in horrible waves and need the cat to “slip” sideways down the waves).
3. Daggerboard cats tend to be built for higher performance, so they’ll be faster, something I also find desirable.

The only minus is that the price-tag tend to be higher than on other cats, so I need to keep my eyes open for good deals.

Quote:

Originally Posted by Gambler

Further, since we seem to have the same prerequisites, I would like to know why the Dean fell of from your list? The Dean is on our short list and I would like to know if there is a reason to revaluate?

It was on my shortlist in the beginning, but after talking to several people I got the impression from them that the Dean was heavy, a bit slow and had a low bridgedeck clearance. I haven’t sailed it yet, so I haven’t experienced this myself. People say the same about the Manta, a boat I really enjoyed, so …
I'd be very interested in hearing your experiences with it.

Quote:

Originally Posted by Gambler

The cats on our list for to day are:

Dean 440 Aero
Dean 40
Outremer 45 - 50
Catana 411
Catana 44
St Francis 44 Mk II
Leopard 45
Kronos 45

I see that the Nautitech is not on your list. Why is it not? To be honest Nautitech is one of the cat designers I’ve been looking at recently (albeit only on the Net.). How was your experience on the 40?
I prefer the 44 over the 40, but the pricetag is tough to swallow.

Quote:

Originally Posted by Gambler

Are you going to start your trip from Norway?

I'm planning to start the actual circumnavigation from Norway, but I’ll have to sail it home first from wherever I buy it.

When are you planning to set sail?

Stella Polaris · 01-03-2008, 00:27

Quote:

Originally Posted by hansdg53

When I was looking at a boat, I read similar threads and in the end, I got so confused that I put it all aside for a while to clear my thoughts.

I completely agree that it can be tough to keep a clear line with so many contradicting thoughts and feelings uttered by fellows on the forum. The thing I hope to achieve by reading posts and talking to a variety of different people is to narrow down my choices and then go from there. In the end buying a boat boils down to gut feeling. Everyone on this forum purchased their boat with a certain list of priorities in mind. I'll do the same. It helps to talk to others, because (hopefully) I'll be able to make a more educated choice. We'll see.

Quote:

Originally Posted by hansdg53

Statistically, you would have more chance finding the boat that is closest to your requirements amongst the extensive fleet of production boats that come out of charter.

My big problem with boats in the charter fleet is that I've seen first hand how people treat them. People treat rental cars nicer than they do chartered boats. Why knows what's lurking underneath the gel-coat?

Quote:

Originally Posted by hansdg53

I don't know how much time you have on your hands, some people say circumnavigation but what they really want is sail in a number of nice places.

I want to do a full on circumnavigation lasting me 4 - 5 years. With my budget I'll be able to buy a boat and sail for said amount of years without having to worry about making money. That's why it's important for me not to spend too much on the boat, because then I won't have enough left to sail for.

Gambler · 01-03-2008, 01:24

Hi again Andreas,

Quote: