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  #1  
Old 08-06-2010, 06:51 PM
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rayaldridge rayaldridge is offline
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Do cats generally need a jib to tack reliably?

I would have said no, from my experience. I've owned two cats, a Wharram Tane, long ago, and more recently, my little beach cruiser, Slider.\

The Tane would usually tack without backing the jib, though as I recall, if I absolutely had to avoid getting into irons, I'd hang onto the jib sheets until the boat was well around. Slider tacks reliably with any sail combination, in any conditions.

I've been suffering a fair amount of angst because my little cartopper cat, which has only a sprit main, no jib, is not a reliable tacker. To me this was a grievous fault, spoiled as I was by Slider's utter reliability.

But the other night I was re-reading one of Thomas Firth Jones' books. Jones was the small cruising multi guru, as far as I'm concerned. He made an offhand statement that cats need a jib in order to tack reliably. Is this really true?
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Old 08-06-2010, 07:08 PM
ThomD ThomD is offline
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I don't know what the general answer is, but today, I went out with the whole family on my small tri, and had great difficulty getting it to tack without the jib up. It was a weight issue among others. I had a reef in too. Anyway, I think on small boats the variables of weight are so great, the more options the better.
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Old 08-06-2010, 07:13 PM
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rayaldridge rayaldridge is offline
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Thom, it's always been my impression that tris will tack as reliably as monohulls, as a general thing.

I think maybe I just got bizarrely lucky with Slider. I haven't found a situation yet in which she will not tack reliably, including a scandalized mainsail only in 30 knots of wind.
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Old 08-06-2010, 07:13 PM
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Depends on the cat. There have been and are many small cats w/o jibs: the Hobie 14 I sailed for a long time tacked fairly reliably, then there is the A class cat and I think Marstrom has a 20 footer w/o a jib. The Hobie Wave, has no jib....I've seen a Blade F 16 sailed locally w/o a jib-seems ok.
My personal opinion is that a relatively heavy boat is likely to tack well and a light boat with long daggerboards is likely to tack well without a jib.
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Old 08-06-2010, 07:21 PM
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rayaldridge rayaldridge is offline
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Doug, Slider is a relatively heavy boat at 16 feet and 500 lbs lightship. But she tacks with her board up just as reliably as with it down.

When you say the Hobie 14 tacked "fairly reliably" what exactly do you mean?

I guess I'm trying to come to some sort of baseline expectation for the new design. If I must have a jib to tack reliably, then so be it, but I'd prefer the boat to tack as well as Slider does. Unfortunately, the new boat will have a 13 foot beam compared to Slider's 8.5 foot beam, so that may also be a factor.
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Old 08-06-2010, 07:33 PM
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Quote:
Originally Posted by rayaldridge View Post
Doug, Slider is a relatively heavy boat at 16 feet and 500 lbs lightship. But she tacks with her board up just as reliably as with it down.

When you say the Hobie 14 tacked "fairly reliably" what exactly do you mean?

I guess I'm trying to come to some sort of baseline expectation for the new design. If I must have a jib to tack reliably, then so be it, but I'd prefer the boat to tack as well as Slider does. Unfortunately, the new boat will have a 13 foot beam compared to Slider's 8.5 foot beam, so that may also be a factor.
-------------
I mean that 95% of the time I wouldn't get into irons-after I practiced with the boat. I like your Slider-you did a great job! In my opinion you might want to consider a jib as:
1) a way to keep the CE lower,
2) a way to easily reef.(assuming the boat sails well w/o the jib).
I've done a lot of model experiments and I was startled by the difference long
narrow daggerboards made as opposed to ,say, boards like the Tornado-on a model(RC) cat with and without a jib. That part of model testing scales up 1 to 1 in my experience.
I've sailed numerous cats and I like the long narrow boards for sailing though they're not ideal for cruising or gunkholing.
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Old 08-06-2010, 08:15 PM
aussiebushman aussiebushman is offline
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The guy who sold me the A Class (now much modified with increased hull volume for use as amas for a cruising tri) included a jib in the sail package, telling me that for cruising situations, the jib was needed for tacking. I have no direct experience of this, but he seemed to know what he was talking about.

Certainly on my former 30' cruising cat, backing the headsail was absolutely essential to get the boat onto the other tack
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Old 08-06-2010, 08:22 PM
CatBuilder CatBuilder is offline
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After a fair amount of experience with cruising cats, I'd say it's not essential to have a job for tacking, but it helps. In my experience, it's more about momentum, as you carve the tack (like skiing or snowboarding) rather than let her come about as a monohull does naturally.
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Old 08-06-2010, 08:36 PM
wardd wardd is offline
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My cats can track mice reliably with out a jib
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Old 08-06-2010, 08:39 PM
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It should not be essential to back the jib in order to tack. But in some situations having a jib is very useful.

For example going from a reach to a reach, or sailing in strong winds and big seas.

I have had difficulty tacking a Laser dinghy in strong winds and big seas (I am not so skillful a Laser sailor as Catsketcher). So it isn't just multihulls that have problems.

If your new boat is having a stayed rig you will almost certainly want to fill the foretriangle with sailcloth at some stage. So I'd design the boat for a jib, even if it isn't used all the time.

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Old 08-06-2010, 08:49 PM
aussiebushman aussiebushman is offline
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Catbuilder - you are absolutely right - it is all about momentum. Mind you, this was sailing on Sydney harbour where it is not always easy to get that momentum as and when needed - every sailor to whom I have spoken agrees this is a bitch of a place to sail due to the constrictions of Fort Denison, the harbour bridge, the Sow & Pigs reef, headlands etc., never mind about the ferries, tugs, container ships and sh*t-head racing yachts coming at you from all directions.

Alan
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Old 08-06-2010, 09:01 PM
SamSam SamSam is offline
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I thought they needed an outboard motor to tack reliably. The next best thing was to back the helm once enough sternway was acquired and complete the operation that way.
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  #13  
Old 08-06-2010, 09:33 PM
ThomD ThomD is offline
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Ray, I agree tris are different than cats, though with enough people on board, not so much.

My point though is that regardless of the boat, people represent more disp on small boats, so there can easily develop situations where one more body, or a preferred position on the boat may lead to a big shift in CLR, and before you know it you will want all you can get to move the boat around.

For instance, install one helmsman in turn on two similar small boats with the same length tiller, and the shorter boat will get higher in the bows, unless the positions were actually dead over cob ( I like the idea of a center cockpit on a small boat). That would be pretty common situation for two home made boats and the longer one could end up tacking better because it is sitting on its waterline better. And it isn't just weight that will push your smaller boat around.
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Old 08-06-2010, 10:13 PM
catsketcher catsketcher is offline
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Gday all

I probably have said this before but here goes - apologies if you heard it already.

My little 6 metre trailer sailer tacks very well, really well. In fact you can shove her up into the wind, stall and sit and then with no jib up give two pumps on the tiller and a trim on the sheet and she will start sailing and then bear away.

She has big rudders. About 60cm in the water for a 6 metre boat is deep. Yet although she will tack like a dream with two rudders down she will not bear away from a stall or tack anywhere near as well with only one rudder down.

After a tack the rudders are asked to cater for the boats weather helm and have very little flow over them so they must be big. Crop duster not fighter jet mentality.

Our 38 footer tacks with no jib with way on. Her overloaded sistership needs the jib backed to tack. Same design, one light one heavy. This just means that overloading causes more headaches than slowness.

Make the rudders efficient on the little one Ray and see if she changes her manners overnight. My bet is that she will be a different boat with NACA 0012 sections and a 500mm deep rudder. I got my rudders from a donor skiff I bought - donor rudders are much easier to modify than build. I used 16ft skiff daggerboards.
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Old 08-07-2010, 01:15 AM
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rayaldridge rayaldridge is offline
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Lots of interesting stuff here. I guess I'm just trying to reassure myself that if the new boat doesn't tack as smartly as Slider, it might still be an acceptable boat.

Slider has deep NACA 0012 rudders with lots of area, and I think that contributes to her windward ability as well as her general handiness. But... she tacks reliably even with the rudders kicked back.

That said, I think you're absolutely correct that many cats have undersized rudders. The big rudders may take off a fraction of a knot at the top end, but undersized rudders make life difficult the rest of the time.

Richard, the new boat will definitely have a jib. I think it's fairly essential for a cruising boat to have at least two sails.
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