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  #1  
Old 05-29-2006, 12:53 AM
Seafarer24 Seafarer24 is offline
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Rig handling: Cat Ketch, Cat Schooner, Sloop, Cutter

This goes along with my other thread regarding a 32' moderate-displacement cruising design.

I figured the rig could stand to have its own thread as I'm torn between designs.

What I like about the Cat Ketch rigs:
*Freestanding masts (with wish-bone booms) means no headsails to repair, no rigging to replace, and less required deck hardware to handle the sails. They're low-maintenance, so they'll cost less in the long-term.
What I don't like about Cat Ketch rigs:
*The first stage of reefing is often striking the mizzen. I haven't sailed a cat rig before, but it strikes me that there would be some funny handling (massive lee helm?) going upwind with just a mainsail all the way up in the bow.
*The last stage of reefing is going to the bow to put a reef in or pull down the mainsail. That's not where I want to be when the weather is so rough that I'm striking all sail.
*Could a mizzen staysail/stormsail be rigged with some running backstays to keep the boat moving with main and mizzen reefed?
How about Cat Schooner?
*This would allow the fore-most sail to be struck first, negating the need to go forward again as the weather gets worse. The mainsail could then be reefed or struck right in the cockpit. Again, could a staysail/stormsail rigged with running backstays be hoisted?

Sloop versus Cutter:
*I'd prefer a cutter, but I don't really want a bow pulpit sticking way out off the front of the boat. A small one for anchors, sure, but as I'm not planing on roller-furling I'd prefer to keep the sails on the deck. At this length, is a cutter without a pulpit still practicle?
*I also like the mast being further aft in the cutter and the sail areas staying pretty centered while reducing sail. In my opinion, balancing reduced sail area should be a serious design consideration in a cruising boat.
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  #2  
Old 05-29-2006, 02:36 AM
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BOATMIK BOATMIK is offline
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This goes along with my other thread regarding a 32' moderate-displacement cruising design.

I figured the rig could stand to have its own thread as I'm torn between designs.

The BIGGEST error that most people make with freestanding cat ketch rigs is thinking they can sheet in the mainsail like on a sloop. If you do the boat will sail very poorly upwind. The most forward sail of any rig should never be brought in closer than 10 degrees to the centreline of the boat.

Regarding sprit rigs and wishbones - IMHO (kids - my opinion only) they are not necessarily better than conventional booms fitted with a beefy vang system.

With a wishbone - if the mast bends in a gust or strong winds the leech goes loose - the clew end of the wishbone moves down and the distance between the clew and tack is reduced. The end result is that camber in the foot can increase excessively - right when you want it nice and flat. They also mean that the wishbone or sprit has to be pushed out forward of the mast when reefing - a bit fiddly compared to just pulling the sail down to a conventional boom. It is all swings and roundabouts - every system has weaknesses and strengths and I am very aware of the sprit's and wishbone's many virtues. (I regularly sail two boats with sprits)

What I don't like about Cat Ketch rigs:
*The first stage of reefing is often striking the mizzen..

I have sailed on Bruce Kirby's Norwalk Island sharpies quite a lot - and I would go with what you are saying - you don't want to put the boat into an unbalanced configuration.

If there was manoevring or upwind sailing or beam reaching to be done I woud keep full mizzen but flatten it with heaps of boom vang. Reef the main until the boat (and/or crew) was comfortable. The only time I would reef the mizzen first is if there was a long broad reach or run - the lee helm becomes a virtue by keeping the nose heading in the right direction with much less helm input

If you boat has a centreboard there is an option to help helm balance with that too. But the first resort to weather helm is flattening (vang outhaul downhaul) and sheeting out the mizzen - it is OK if it is luffed almost entirely in gusts - there is a strong advantage in a fully battened mizzen because of this. If you are racing put your best crewman on it and get him to watch your tiller angle to make sure weather helm doesn't become too excessive.


*The last stage of reefing is going to the bow to put a reef in or pull down the mainsail. That's not where I want to be when the weather is so rough that I'm striking all sail.

Generally we set up foreward and aft reefing lines going back to the fore end of the boom, then the mastbase and back to the cockpit. It is not where we want to be either! :-)

Spending time to get the system right and working smoothly is a great safety feature.


*Could a mizzen staysail/stormsail be rigged with some running backstays to keep the boat moving with main and mizzen reefed?

Some have done it - ie staysail for downwind off mizzen but as a stormsail - bad idea - you will just break the unstayed mast unless it is engineered so heavy that the response in light and medium winds is damaged.

The is for the fun of the colourful kite only - it has no noticeable performance benefit. Use for light to moderate winds only. Tie a figure 8 knot in the staysail halyard about a foot away from the top of the staysail. When you hoist the staysail the knot comes up against the halyard sheave then can be taken to the windward mooring cleat. Tensioned it pulls the masthead back and to windward. The staysail should not be used in stronger winds - it will rip the top off the mast.

Like I said the staysail is only for fun. For PERFORMANCE you can whip any spinnaker boat on a broad reach by running goosewinged - but almost everyone does it wrong. They let the mainsail choose its side and then push the mizzen over so it is by-the-lee. This configuration means that the mizzen is simply blanketting the mainsail unless your are on a really square run.

Doing it the right way you let the mizzen flip to the side it wants and run the main by the lee - sounds scary but on an unstayed rig you can let the main out 10 degrees forward of the normal running position. Use lots of vang on both sails and watch her go. If you have attached flow (tufts on the main flowing crank the foot up to a 1 in 7 camber (upwind it should only be a tame 1 in 10 or a bit fuller depending on the boat

The air that is forced either side of the mizzen results in accelerated flow on the windward side of the mast - which goes straight at the mainsail. Same effect as running downwind with the fleet astern but to one side.

Every square inch is working in a beautifully flat projected area. Compare with a spinnaker which has almost half of its area hiding behind the mainsail and poor projected area because of the large camber.

How about Cat Schooner?

You would only lose some of the upwind performance unless the rig was pretty well sorted. Do you know enough to do this in an efficient way?

*The mainsail could then be reefed or struck right in the cockpit. Again, could a staysail/stormsail rigged with running backstays be hoisted?

Why consider mucking up a perfectly nice, simple rig with running backstays. :-) They only give you ways of breaking the boom or reasons for yelling at the crew

No reason to have them.


Sloop versus Cutter:
*I'd prefer a cutter, but I don't really want a bow pulpit sticking way out off the front of the boat. A small one for anchors, sure, but as I'm not planing on roller-furling I'd prefer to keep the sails on the deck. At this length, is a cutter without a pulpit still practicle?
*I also like the mast being further aft in the cutter and the sail areas staying pretty centered while reducing sail. In my opinion, balancing reduced sail area should be a serious design consideration in a cruising boat

Having a balanced sailplan is important - but it can be organised correctly with many different rigs including sloop if the designer has done a good job of matching the hull and the rig. Sometimes you want the rig to be out of balance (as with the mizzen down running long distances in stronger breezes example above.)

Hope this helps

Michael
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  #3  
Old 05-29-2006, 05:33 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
A properly designed cutter need not have a bow sprit , or the forestaysail tacked to anything but the deck.

If you need to work foward in snotty weather here are a few tips.

When you build the boat a collision bulkhead a couple of ft back from the bow is easy to build in and has multiple advantages. Primarily the deck foward of the top of the bulkhead can be lowered a foot or so.
Now when your foward youre almost in a sheltered cockpit , with the bow pulpit a foot higher than "normal" a fine feeling.

The anchors can pass thru hawse holes , and be secured, leaving the mud & grunge outside the boat , for Father Neptune to wash for you.

If you create a wire line from the bow pulpit to the tack of the forestaysail , it can be used as a lazy stay.

To change sails , you drop the outer jib , and starting at the lowest hank clip the lowered sail to the lazy stay.
Then hank the next sail onto the forestay from its lazy stay.
Move the tack shakle and the halyard and youre ready to hoist.

This takes less time to DO it than type it , and at no time is there a risk of loosing a sail overboard , or need to drag/live with a big wet bag of sail below..

Additionally inshore , under self steering or autopilot the bow well makes a fine tiny cockpit for watching the scenery go by.

FAST FRED
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Old 05-29-2006, 03:30 PM
Seafarer24 Seafarer24 is offline
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BoatMik- My sole experience with freestanding masts was going aboard Freedom 40 #1 (Modesty) and having a long talk with its owner (who is a rigger by trade). The boat has running backstays on the mizzen and can hoist a 600sq.ft staysail for use offwind. He says it's only good for covering long distances on the same tack (as it must be dropped to tack), but is a real performer. Since I'm planning to make a long-distance cruising boat that will sail primarily in the trade-winds, this sounds like a good sail to have.

Regarding sail trim, I've always figured that the fore-most sail on a cat-ketch should be treated more like the head-sail of a sloop, rather than it's counterpart on a traditional ketch. Is this about right? The owner of Modesty said he'd set his course, trim the main to pull, then trim the mizzen to hold the course and lock the wheel. The boat would then self-steer. I thought to ask "what keeps you on course after you douse the mizzen", but for some odd reason witheld. I'm planing on a windvane for course-keeping.
I'm considering making both main and mizzen each 250-300sq. ft. and just reefing whichever as the situation calls. The Freedom 40 sports two equal-height masts each with 450sq.ft. of sail and the afore-mentioned 600sq.ft. mizzen staysail.

My idea for a heavy-weather storm staysail would involve using a halyard to pull the head of the sail and two stays partially up the mast. The stays would be attached to deck cleats, the sail (with a wire luff) would have the tack attached to a deck eye, and then the whole setup would be hoisted with an external halyard until everything was taught. It wouldn't be going particularly far up the mast, maybe 20' or so. Just enough sail to steady the motion of the boat in gale-force winds and keep from rounding up.

Fast Fred- the bow well is an excellent idea, but I'm not entirely sure there is enough room for such a feature on a 32' boat. However, you can be sure I'll try to encorporate it if I go with a sloop or cutter rig.

The lazy-jack method was well-written and I like that idea as well.
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Old 05-29-2006, 08:02 PM
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BOATMIK BOATMIK is offline
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BoatMik- My sole experience with freestanding masts was going aboard Freedom 40 #1 (Modesty) and having a long talk with its owner (who is a rigger by trade). The boat has running backstays on the mizzen and can hoist a 600sq.ft staysail for use offwind. He says it's only good for covering long distances on the same tack (as it must be dropped to tack), but is a real performer. Since I'm planning to make a long-distance cruising boat that will sail primarily in the trade-winds, this sounds like a good sail to have.

Howdy Seafarer - I would take that information seriously - but at the same time I would be asking the question whether the staysail will just be interfering with the main.

See what turns up in this thread as far as advice from people who have done the miles - they are not always right as individuals on every point but the group knowledge is very valuable.


Regarding sail trim, I've always figured that the fore-most sail on a cat-ketch should be treated more like the head-sail of a sloop, rather than it's counterpart on a traditional ketch. Is this about right?

Perfect - if the most forward sail is sheeted out at around 10 degrees to the centreline for upwind work - that's it. And Lazyjacks are the Bee's Knees

My idea for a heavy-weather storm staysail would involve using a halyard to pull the head of the sail and two stays partially up the mast. The stays would be attached to deck cleats, the sail (with a wire luff) would have the tack attached to a deck eye, and then the whole setup would be hoisted with an external halyard until everything was taught. It wouldn't be going particularly far up the mast, maybe 20' or so. Just enough sail to steady the motion of the boat in gale-force winds and keep from rounding up.

I think a heavy weather staysail on the mizzen is a bad idea. A sail flying on a stay requires huge tensions to stop the luff from sagging. Heavy weather is also a highly loaded situation (said he obviously!!!). Masts designed for free standing rigs are set up to bend to give the boat excellent gust response through the masts bending automaticallly as the gusts come and go - shedding power for you automatically.

1/ You will be loading the masts with significant compression - which they were not designed to deal with - risks are masts buckling out of column or breaking the mast support structure inside the boat. Even with stayed boats the way to reduce rig loads in heavy winds is to get the jibs off and use a dramatically reduced mainsail or trisail - both of which add much less tension to the rig (and thus less compression to the mast and less stress to the hull) for the same amount of propulsion.

2/ The flexible masts will never allow you to get the staysail luff properly tight. If you have ever sailed in a boat where the jibstay becomes slack you will know the behavior downwind or reaching as the sail pushes the forestay around in a self exciting cycle - snapping full of breeze one moment and swinging around to be luffing the next. Not good behavior for a storm sail.

3/ The Freedoms and other Unstayed cat ketches have been around for a long time now - they must have dealt with some pretty nasty conditions - are you sure you are not thinking too complicated and trying to resolve a problem that doesn't exist? Speak to 'em and see what this thread pulls out.

4/ A set of running backstays on the mizzen mast for the spinnaker staysail. Plus a second set for reefing - are you sure you wouldn't be happier on a gaff schooner?

5/ Maybe someone else with have a clearer idea but I suspect a staysail luff running at such a flat angle (20ft up and 25ft forward?) will develop a lot of lifting force - not sure if that is what I would want in a gale. Also might increase power as the boat heels rather (increasing projected area) than reducing as with a more upright luff - I am sorta thinking through the 3D picture here. As a thought experiment - imagine a sail set up on a horizontal wire and sheeted out from the centreline. There would only be heeling force - no forward force and the maximum heeling moment would be when the boat was heeled enough for the sail to become vertical. The closer the storm staysail wire is to the horizontal the closer it will match this scenario


Fast Fred- the bow well is an excellent idea, but I'm not entirely sure there is enough room for such a feature on a 32' boat. However, you can be sure I'll try to encorporate it if I go with a sloop or cutter rig.

The lazy-jack method was well-written and I like that idea as well.
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Old 05-29-2006, 11:39 PM
Seafarer24 Seafarer24 is offline
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Alright, you've completely typed me out of any sort of storm staysail.

Now I guess the only questiong is: Cutter or Cat Ketch for a solo-circumnavigator capable boat.... I get the feeling it comes down to personal preference rather than one rig being more capable than the other for this useage.
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Old 05-29-2006, 11:53 PM
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BOATMIK BOATMIK is offline
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Quote:
Originally Posted by Seafarer24
Alright, you've completely typed me out of any sort of storm staysail.

Now I guess the only questiong is: Cutter or Cat Ketch for a solo-circumnavigator capable boat.... I get the feeling it comes down to personal preference rather than one rig being more capable than the other for this useage.
That's EXACTLY it!!!!

I would go for a sloop with a short footed jib (tack kept well back from the stem) and a roached fully battened mainsail. No backstays at all. Drop the main to halfway and douse the jib and its all in perfect balance again. Did you consider that as an option? :-)

But to the point of this post ...

Virtually any type of rig will get you round the world. Getting things to work properly and safely is much more about boat set-up than it is about rig.

So rig choice comes down to what is available - at what price - and what you like.

If it is what you want to do - be like the ad - and just DO IT! :-)

Looking for perfect solutions can be a way of stalling something you are a bit nervous about (have seen the same thing dozens of times when I've run boatbuilding classes) - it's perfectly normal and welcome to the human race!!!

And I am sensible enough to see the same tendency in myself too - sometimes it trips me up.

Generally the thing that a blue water sailor (or builder for that matter) needs is the ability to solve practical problems as they arise - be careful not to get tooooo caught up in intellectualisation about finding "the best" solution. They don't exist.

All you can ever hope for is something that WORKS. And that might be enough to make the difference between a scared, tired crew and one that is looking forward to the next challenge (after a few weeks looking over Rhodes or Tahiti - of course).

Good luck - YOU can do it with ANY rig.

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Old 05-30-2006, 10:23 AM
Seafarer24 Seafarer24 is offline
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I suppose I do have a few more questions regarding the cat ketch rig:

Wishbone vs Boom?
It's a cruising design, but I plan on using fully battened, roachy sails no matter which control system I use. I like that with a wishbone you have no need for a traveler. Monohulls are too narrow to really make good use for a traveler, and most of them only cross the cabin-top or the narrow end of the stern anyhow. They end up around 6' in length at best. That is where vangs come in handy, of course, keeping the boom down when the sheet is let out.

However, which is easier to reef? Both can be fitted with lazy-jacks, but only booms can have jiffy-reefing, right?
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Old 05-30-2006, 11:06 AM
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I don't have enough real experience to be definitive here but would offer areas I would explore.

The normal booms do allow jiffy reefing and that's the reason for my preference in that direction - the lazyjacks hold the booms in position and you just have to be concerned with dealing with the sails. The booms are just static.

Because the wishbones have to move forward of the mast to trim the new shorter foot of the reefed sail as well - it all seems more complicated.

Certainly seemed that way when I was part of a charter crew on a Freedom 32 years ago - but maybe that was because we didn't know something that we should have. The most obvious step would be to set up preset marks on halyards and snotter.

Certainly if I did have conventional booms the foots of the sails would be cocked up pretty much how the foots of the wishbone sails are organised - to keep them out of the water when they are eased and the boat is rolling around. Actually you can have the best of both worlds by having the foot more horizontal but setting up the reefing positions in the sail to keep the booms cocked up - but maybe that causes more mucking round than is really sensible - the toooo intiellectual trap!!! Keep it simple - make it right.

Enough boom clearance forward for efficient vangs - as per blue water racers.

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