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Jose Carumba

WLYDO critique of the Presto 30

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The (mythical) front page highlights the Presto 30, a sharpie style cruising boat. It would be fun to critique this design. I think this is a pretty cool little boat. I might like a removable keel like Bob's box boat or a weighted daggerboard but overall the design meets my criteria for a small, light, easily sailed, trailerable cruising boat.

 

What say you?

 

http://unionriverboat.com/index.html

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To me, it looks more like the LFH Meadowlark than Presto. Other similar boats are the Norwalk Island sharpies, and various Phil Bolger designs.

 

Boats like this have enough virtues that that new designs appear from time to time, and enough vices that they remain a niche item. A centerboard boat is not going to have power to carry sail of a keel boat, and upwind performance will suffer. Heavy weather performance will suffer. The light hull will do very well offwind in wind speeds above a drift. The rig should be easy to handle. If it's not, for some unknowable reason, the boat has no point at all.

 

I think the whole point is the ability to float in very shallow water. For some people, this is needed for docking/mooring; for others, it suits their desired cruising ground.

 

For a small builder looking to avoid head-to-head competition with the big boys, it's an interesting choice.

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I don't think it's a bad boat if your cruising ground is NC sounds, FL Bay or even the Maryland/VA lower Eastern Shore or somewhere else like that - read <6' kind of shallow. But.......an USD 85K daysailer without electronics, trailer, etc. That sucker is going to be $100K out the door.

 

IB

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I love the concept of the Presto. The original was a boat that really hit at my heart. The hull form was freakishly modern with flat bottom, flare, and a fine entry. I like the idea of modernizing it with lightweight spars and retractable propulsion. But somebody needs to do something about that deckhouse - too 70's for my taste. And the renderings need to be done by Sons to give them a little more life :)

 

In a little larger boat I think they do well with a high amount of internal ballast, similar to the Southerlys. For this trailerable version I think you mostly go for form stability and give up the pointing. With a narrow hull she should be able to power into it pretty well especially with a mostly retracted keel.

 

Other than the deck house I like the design, but I'll go to the Maestro for mine, thankyouverymuch. Make mine a yawl please, I like to be able to manhandle the mizzen and feather the boat.

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I knda liked the concept until I got to the $85K ????

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It is one of those boats he designed for hurricane island. Just cleaned up the hull form a bit because it didn't need to be rowed well, and added the cabin. Or at least, it said something like that on the website. Good eye!

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I don't really know what the target market is for this boat. It is very light which should make for uncomfortable rides in a seaway and probably will get bounced around fairly easily at anchorage. The rigs look out of proportion probably because it is so light she can not handle a lot of canvas. I like the bronze centerboard but would prefer a keel to go with it.

 

Will Museler

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I thought the centerboard was glass... that is just had bronze... what do you call it, swiveling hardware....etc.

- Czo

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It makes the masts easy to raise by hand and easy to stow on the trailer. It may not necessarily make the boat sail any better.

 

I wouldn't buy one. It depends too much on light weather.

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It makes the masts easy to raise by hand and easy to stow on the trailer. It may not necessarily make the boat sail any better.

 

I wouldn't buy one. It depends too much on light weather.

 

Would work great in the south and midwest freshwater.

 

Unfortunately, that's not a big enough customer base. Wouldn't be something I'd want to seriously sail a lot.

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I like the concept and one of the earlier WLYDO boats was going down this path in terms of a shoal draft day-sailer/weekender. I agree with Jose re: the keel and Bob's approach. If I wanted to split the rig, I'd do a cat yawl or ketch so that the mizzen isn't forcing the companionway off-centre. Other than that, as much as I like some of his other designs (e.g. Aerodyne 38 - fast boat and combines sensible interior layout), I think this one looks like it would have a few vices and restricted weather range.

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Like the concept. Not crazy about the design from the back of the house aft and the cockpit (especially the coamings). I don't even think $85k is all that bad for a 30'er.

 

but, swinging appendages give me the heebee geebees. Everyone I know who has a swinging keel or rudder has broken the chain/cable/rope/whatever used to pull the thing up at least twice.

 

Personally, if I were going with a moveable keel, it would be a lifting type. I can deal with the housing. Folks don't spend so much time inside the freakin' boat anyway. Too much emphasis placed on the interior when folks are hardly there.

 

I ramble...

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If I wanted to split the rig, I'd do a cat yawl or ketch so that the mizzen isn't forcing the companionway off-centre.

 

The cat-ketch rig is traditional for sharpies, of course. The original New Haven sharpies were working boats, and sailing performance was not the most important thing. Features should be copied from working boats to yachts with caution. In addition to keeping the masts short, it keeps the center of area low so the sailing performance can be acceptable in lift air, at least off the wind.

 

Phil Bolger designed more sharpies than anyone, and he preferred a cat-yawl. He liked the way the mizzen was in the stern out of the way, and suggested that it be full-battened and left hoisted at all times. I think he also felt that overall sailing performance was better.

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Rodger Martin would be the one to put this together. I saw his open design a few years back when it was a proposal so this is not new to him.

 

Sail area. I would think that it needs to be much more variable. I think the numbers will make sense but having watched some of Gary Hoyts creations the need for a ton of sail area in light wind and then several reef points is needed more so then a conventional boat. Perhaps some form of sleve for the masts in order to get additional height but still keep the longest section under 30 feet. That had better be a swing keel and not a centerboard! Also it does not mention an outboard well or any power option. Usually there was a well shown on the PB designs. If I was retired and lived on the East Coast especially south of Hatteras this would work rather well.

 

This is a good post. I get the feeling that you guys could improve this just enough to sell some hulls. The price is better than I expected. Not that it is good just better than I expected.

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

Initially I liked it, BUT......at $85k you want shallow draft and performance sailing plus cruising comfort of sorts. Really sounds like this design is missing another hull or two. As the full on cost will most likely be six figures, well, bite the bullet and redesign the concept as a catamaran. Sharpies are cool, but still pretty much just so 19th century.

 

If one must stick with one hull, a lifting keel is the first revision. With better righting moment the sail plan could then be upgraded. Wait a minute.... where's the designer?

 

Didn't Gary Mull do some sort of Freedom cat ketch design back in the late 70's?

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pretty boat lines - wasn't too concerned about the price as I don't know what CF masted 30'er you can buy for $85k new. Not concerned about the wishbones either, as Wylie, Nonsuch, and Freedom (and there was a wishbone herreschoff as well that did well) all seem to have had good success with the concept. However, Freedom learned pretty early that you need more forward volume to handle a cat rig like that, or it becomes a cat submarine - if you need proof, google "Wobegon Daze" and see how much work Dr. Cady had to do to a Freedom 36 to make it seaworthy.

 

I don't see the wishbone being an easy rig to dismantle, but that depends on how the controls are set up. I don't see people really wanting to rig and derig two masts on a 30er very often, if at all, no matter how much the masts weigh. For freestanders, you have to keel-step them, so in addition to getting them up without damaging them, you then have to replace deck wedges, pin them so they don't rotate or jump out in the waves -- adds to the rigging time and extreme attention to detail if you're going to do this often.

 

That said, the cat-ketch rig is a powerful rig as long as you don't care about pointing - my Freedom 40 CK tacked through about 100 degrees on a good day, 90 if I got everything balanced right, but then was a dog upwind. And for those who thing $85k is too much, check out a Shoalsailer 32 (admittedly more boat but similar concept) at $158k for a 2004.

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

Initially I liked it, BUT......at $85k you want shallow draft and performance sailing plus cruising comfort of sorts. Really sounds like this design is missing another hull or two. As the full on cost will most likely be six figures, well, bite the bullet and redesign the concept as a catamaran. Sharpies are cool, but still pretty much just so 19th century.

 

If one must stick with one hull, a lifting keel is the first revision. With better righting moment the sail plan could then be upgraded. Wait a minute.... where's the designer?

 

Didn't Gary Mull do some sort of Freedom cat ketch design back in the late 70's?

The Freedom 40 Cat/Ketch a Gary Hoyt design, one of my all time favorites:

 

main.jpg

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Didn't Gary Mull do some sort of Freedom cat ketch design back in the late 70's?

 

It was Gary Hoyt, working with Halsey Herreshof. They started with a 40', but followed up with a 44 and a 35 and maybe others. Called it a "cat ketch" but it was technically a schooner, and pointed just as poorly as any other schooner.

 

The technical distinction here: if the masts are the same size, it's a schooner, not a ketch.

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I knda liked the concept until I got to the $85K ????

why is 85k bad for a 30 footer? that is pretty much in line(if not cheap) with new boat prices that I have seen. If you can show me a 30 foot coastal cruiser for less, new, I would love to see it, serious on this not sarcastic. 75k is about my max if I am not using the boat as a house and I am TIRED of used boat headaches.

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Didn't Gary Mull do some sort of Freedom cat ketch design back in the late 70's?

 

It was Gary Hoyt, working with Halsey Herreshof. They started with a 40', but followed up with a 44 and a 35 and maybe others. Called it a "cat ketch" but it was technically a schooner, and pointed just as poorly as any other schooner.

 

The technical distinction here: if the masts are the same size, it's a schooner, not a ketch.

 

They were cat ketches. the technical distinction is that if the masts are the same height, (or the aft taller than the fore) it's a schooner. Freedom only made one true schooner, the Freedom 39 Pilothouse. The 40 and the 44 had masts the same length, but the main mast on both was stepped about 2 - 3 ' higher than the mizzen. Hence, a ketch.

 

In the us, the cat ketches were the 28, 33, 36/38(as an option - was usually a sloop,which performed much better because of the aforementioned bow volume issues), 39 Express, 40, and 44. Most of these were also produced in the UK but with different length indicators (e.g. the US 33 was billed 35 in the UK).

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I think it looks like a neat boat, with some good people behind it. Obviously, the boat is not meant to be a heavy weather upwind machine and/or cross oceans-but for what she is meant for-skinny water, summer conditions, ease of launch/rig/storage - I bet it will be one great little boat and will likely sail alot better than some of the pundits might think. Roger Martin is a good and clever guy who knows about performance and his initial client-Phil Garland-is not exactly an inexperienced cruiser looking for some sort of character boat. Don't be surprised if you see this little boat come xipping past you in 4 feet of water one day!!

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but, swinging appendages give me the heebee geebees. Everyone I know who has a swinging keel or rudder has broken the chain/cable/rope/whatever used to pull the thing up at least twice.

 

Personally, if I were going with a moveable keel, it would be a lifting type.

 

Inspect and replace underwater stuff frequently!

 

Swing keels kick up when you hit stuff. Daggerboards snap off. Notice I said WHEN you hit stuff. Shallow water cruiser, here!

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With a light ship SA/D of 24.6 and D/L of 68.7 (based on a 29.5' lwl) this boat will not be a slouch. The numbers will change a bit as you add people and gear but they still make the boat a pretty high performance cruiser. I am not sure about pointing ability with the rig shown but I think it will perform as well as most dedicated cruising boats, and, as noted in the literature, if you foot off a bit you may make back some of that VMG. It was nice that they provide the design polars.

 

I like simple accomodations. I don't need a lot of fancy stuff and am content with slouching headroom, but then again I am only 5'-8" (or was). For my taller friends there is the pop top and 6'-9" settee berths (I'll sleep in the cockpit. I snore like a freight train). Even though I like deep keels the thought of nosing in to the beach in some small cove holds a lot of appeal. The optional electric propulsion package sounds pretty good too, but I'd carry a small generator just in case. This is not an ocean cruiser but for inshore work it would be just fine.

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You know with those dimensions I think it will fit tilted in a 40' shipping container....I think there is a guy who posts here who know all about the inside of a container and how to build em cheap....

 

Flying Tiger Schooner anyone?

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personally, sounds like the perfect trailer sailor for a trip cross-country into the Sea of Cortez. Or The Keys.

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A couple of other boats in about the same niche:

 

Sea Pearl 28. Ted Brewer design, I think.

http://www.seapearlboats.org/html/my_boats.html

 

The Sharp End 900 in the current issue of WoodenBoat (Blue boat pictured for article on page 60)

http://www.woodenboat.com/wbmag/pdfs/209toc.pdf

 

 

O.K., so now I'm confused as to just how good/bad a sailor this really might be. Anybody good at translating Dutch ???

 

http://www.whitewatersharpie.com/whitewatersharpie.htm

 

Guess the only way to really find out is to book a test sail.

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A couple of other boats in about the same niche:

 

Sea Pearl 28. Ted Brewer design, I think.

http://www.seapearlboats.org/html/my_boats.html

 

The Sharp End 900 in the current issue of WoodenBoat (Blue boat pictured for article on page 60)

http://www.woodenboat.com/wbmag/pdfs/209toc.pdf

 

 

O.K., so now I'm confused as to just how good/bad a sailor this really might be. Anybody good at translating Dutch ???

 

http://www.whitewatersharpie.com/whitewatersharpie.htm

 

Guess the only way to really find out is to book a test sail.

 

You'll need to find a current issue of Wooden Boat or wait until it is converted to digital when the next one comes out I guess. The article said the boat sailed very well, but you know, most magazine's have never met a boat they didn't like.

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... but you know, most magazine's have never met a boat they didn't like.

 

So true.

 

Here's another generalization. Mr. Perry HATES generalizations.

 

Any boat with internal ballast only is going to have a smaller range of conditions in which it sails well than can be designed into a boat with a deep keel. (This was noted above in a couple of different ways.) A good designer can put the sweet spot so that the best sailing happens in the most common conditions. The owner is happy as long as he doesn't race against keel boats and the weather remains fair.

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... but you know, most magazine's have never met a boat they didn't like.

 

So true.

 

Here's another generalization. Mr. Perry HATES generalizations.

 

Any boat with internal ballast only is going to have a smaller range of conditions in which it sails well than can be designed into a boat with a deep keel. (This was noted above in a couple of different ways.) A good designer can put the sweet spot so that the best sailing happens in the most common conditions. The owner is happy as long as he doesn't race against keel boats and the weather remains fair.

 

 

Yep, that's a generalization. You do make a good point but an example of why this generalization can be misleading are the Ted Hood "deep bellied", relatively heavy, internally ballasted centerboard boats which sailed well across the board.

 

I think one of the ways Rodger Martin widened the sweet spot on the Presto 30 was to split the rig to lower the center of effort while keeping the sail area relatively high, allowing the boat to stand up and still have some power as the breeze increases, the trade-off being a bit of reduction in pointing ability. Design is a balancing act. Add something here, take away something there, move a little bit of somethig 6".

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Personally, if I were going with a moveable keel, it would be a lifting type.

 

I agree.

 

It is a cool Bahamas boat though. Would you even need a dinghy for a boat like that?

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When the swing keel breaks off and that bitch sinks I'd use the dinghy as a lifeboat :o

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When the swing keel breaks off and that bitch sinks I'd use the dinghy as a lifeboat :o

 

I think, perhaps, that more boats with fixed keels have had the keels fall off than swing keel boats, at least in the past 10 years or so. Of course we're talking high performance bulbed fins. Swing keels work just fine and actually ride up and over obstructions on the bottom. Just don't back up into a rock at 5 knots! Maintain the pivot and raising mechanisms regularly, like you would inspect and tighten your keel bolts on a fixed keel vessel and you should be fine.

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When the swing keel breaks off and that bitch sinks I'd use the dinghy as a lifeboat :o

 

Why would a swing keel break off?

 

Why would a boat that could easily have positive buoyancy ever sink?

 

Here's what happens when you apply negative stereotypes (and the assumption of incompetent engineering) where they don't really apply.

 

I've sailed lots of boats with swing keels & big daggerboards (ie bigger than a Sunfish etc). I'd prefer the lower maintenance & higher sailing performance of a daggerboard.

 

The Presto 30 looks great to me (except for the off-center companionway) but don't know if I'm ready to pony up 85k$ for one. Besides I can tell you right now our local PHRF committee will hate it.

 

FB- Doug

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When the swing keel breaks off and that bitch sinks I'd use the dinghy as a lifeboat :o

 

Why would a swing keel break off?

 

Why would a boat that could easily have positive buoyancy ever sink?

 

Here's what happens when you apply negative stereotypes (and the assumption of incompetent engineering) where they don't really apply.

 

I've sailed lots of boats with swing keels & big daggerboards (ie bigger than a Sunfish etc). I'd prefer the lower maintenance & higher sailing performance of a daggerboard.

 

The Presto 30 looks great to me (except for the off-center companionway) but don't know if I'm ready to pony up 85k$ for one. Besides I can tell you right now our local PHRF committee will hate it.

 

FB- Doug

Steam,

 

Talk about stereotyping: "Besides I can tell you right now our local PHRF committee will hate it."

 

There is nothing radical about this boat, nothing that has not been done before. There are Freedom's out there with the same rig setup and there are dagger board boats out there as well.

 

I don't get this aversion to the off center companion way, why?

 

Will Museler

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When the swing keel breaks off and that bitch sinks I'd use the dinghy as a lifeboat :o

 

Why would a swing keel break off?

 

Why would a boat that could easily have positive buoyancy ever sink?

 

Here's what happens when you apply negative stereotypes (and the assumption of incompetent engineering) where they don't really apply.

 

I've sailed lots of boats with swing keels & big daggerboards (ie bigger than a Sunfish etc). I'd prefer the lower maintenance & higher sailing performance of a daggerboard.

 

The Presto 30 looks great to me (except for the off-center companionway) but don't know if I'm ready to pony up 85k$ for one. Besides I can tell you right now our local PHRF committee will hate it.

 

FB- Doug

Steam,

 

Talk about stereotyping: "Besides I can tell you right now our local PHRF committee will hate it."

 

There is nothing radical about this boat, nothing that has not been done before. There are Freedom's out there with the same rig setup and there are dagger board boats out there as well.

 

I don't get this aversion to the off center companion way, why?

 

Will Museler

 

An off-center companionway that is open during a knock-down to the side the companionway is on is the danger. That's the only big nit I have to pick with this design.

 

I would call this a fair weather coastal cruiser, ideal for the Chesapeake or the the NC sounds - in those waters there is a difference of an order of magnitude between the number of anchorages available to this boat vs. one with a 5' draft.

 

Another advantage to these shallow draft designs is that when you do run aground, which you will inevitably do, you can step out of the boat and push the boat free. If the boat only draws 1' 2" of water you're only going to be up to your knees while doing this.

 

I would prefer a yawl with both the main and mizzen being a low aspect square top (i.e. a modern gaff rig). That would take care of the companionway problem without adding some new problem and keep the CE low.

 

If I had $85K to spend on a boat I wouldn't buy this one.

 

romaine

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Why would a swing keel break off?

Why would a boat that could easily have positive buoyancy ever sink?

An off-center companionway that is open during a knock-down to the side the companionway is on is the danger.

 

These things come down to design, engineering, build, and maintenance. That gives four chances for something to go wrong, but I'll eat my hat if Roger Martin failed to calculate that the hatch opening will be well above water with the boat on her beam ends. That's a pretty basic matter. Lots of old-time centerboard boats had either twin hatches or a very wide hatch since the centerboard is in the way, as it is in this boat.

 

I think one of the ways Rodger Martin widened the sweet spot on the Presto 30 was to split the rig to lower the center of effort while keeping the sail area relatively high, allowing the boat to stand up and still have some power as the breeze increases, the trade-off being a bit of reduction in pointing ability.

 

Looking at the lines on Roger Martin's website, I see the waterline beam is quite a bit less than max beam. That lowers the internal ballast when upright, lessens wetted surface, and gives you a lot of reserve stability to lean on as the boat heels.

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These things come down to design, engineering, build, and maintenance. That gives four chances for something to go wrong

 

In either the design or the build.

BUT it's amazing to me (as a card-carrying pessimist & cynic) how many times these things are actually done RIGHT (or close to it).

 

We can't blame the designer & builder for maintenance issues, but it heps if they make it easy from the beginning.

 

I'll eat my hat if Roger Martin failed to calculate that the hatch opening will be well above water with the boat on her beam ends. That's a pretty basic matter.....

 

He's a great designer, I've sailed a couple of his boats. There's always compromise, but I just don't like external asymmetry in boats (or women). Silly of me.

 

IMHO it's a good reason for a daggerboard instead of centerboard... takes up far less room, adds strength instead of weakening, better hyrodynamics. Or is the issue the mizzen mast & step, not the CB trunk?

 

FB- Doug

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The neat thing about the cat-yawl rig as designed by Bolger was that when you reefed the main, the center of effort remained pretty much in the same area and was well balanced single and double reefed. The cat ketch wasn't so easy to keep balanced that way. Shoal draft kind of cuts a couple different ways, good for shallow anchorages but not for shallow water sailing usually as the board needs to be down to still go to weather and then the shallow draft aspect basically goes away. I love shallow draft though, even on a big boat like mine. With two boards down only a foot or so below the hulls, I have as good a performance to weather as a mini keel. (okay, we ARE talking a catamaran here)

 

This boat seems to be just another run of the mill shoal draft cat ketch imitating those already out there and previously mentioned, also cheaper on the used market. Nothing to see here, move along.

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This boat seems to be just another run of the mill shoal draft cat ketch imitating those already out there and previously mentioned, also cheaper on the used market. Nothing to see here, move along.

 

?? Please point to a modern planing hulled resin-infused cat-ketch on the "used market."

 

Seems to me like quite a step up from anything produced by those usually interested by traditional boats or homebuilt boats. The only thing remotely similar I can think of is Chuck Paine's Bahama Sandpiper and that's in a competely (competely!) different D/L an SA/D category.

 

FB- Doug

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I am probably missing something, but a 30 foot trailable boat? Where do you put the truck and 30 foot trailer when you launch it? In my area there would be no place to put the rig (total 50 feet). Perhaps the idea is you pay someone else to drag it around. I do like the simple plan and shallow draft. Even in the pacific northwest this would open up lots of anchorages, and give you options even on busy weekends in crowded areas where you could get close to shore, or even tie off to a tree for the night.

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Those who will be attracted to this boat based on the 'planing hull' and resin infusion can likely be counted on one hand. The attraction of this design is shoal draft, cat ketch, (potential) trailerability etc. Sandpiper, some of the 'Hens', Norwalk Sharpies etc fit those parameters. You can always build a boat in a 'new' method/material/lighter weight but this is not break thru design any longer. Attractive to some with deep pockets, perhaps, but I still maintain that it's 'run of the mill' from a design standpoint if not from a construction standpoint.

 

Don't get me wrong, it's not a bad boat. It just tries to do what most every boat in that size range tries for. Me? I really liked the idea of the Outward Bound new designs that this is supposed to be based on. New and innovative would be to treat it like a 30' (whatever the length is) small boat and adapt it to a small crew of one or two. I'd really like to see some long small boats on the market. Take most any of your typical 18-24 footers and just essentially stretch them out and get a little more elbow room, not more bunks and full headroom. If folks can stand small and low in a 21'er, they can deal with it in a 28-30'er with a touch more proportional room up/sideways etc. That's what I would consider innovative and creative. Probably sell just as many at what will undoubtedly be 'too much money' for a boat that _____".

 

Today, there seems to be an almost automatic shift once one goes beyond trailerable to making a boat have 'everything the bigger boats have'. Once that happens you've shifted in your whole sailing mindset/expectations. Now you just have a small 'big boat'.

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Mea Culpa.

 

Okay, I went back and checked out their website. They DID do more what I'm talking about. I'd still like to see a different rig and cockpit layout but I take it all back.

 

(I told myself this is what I get for skimming an article and whipping out a careless quick response but who would listen?)

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...I'll eat my hat if Roger Martin failed to calculate that the hatch opening will be well above water with the boat on her beam ends. That's a pretty basic matter.

 

Also, even a centered companionway should be closed and latched in conditions where a knockdown is possible.

 

Also, I don't know anyone who has been knocked down and was not asking for it at the time.

 

Also, those darn cockpit lockers are what take on huge amounts of water when boats are knocked down, and very few builders make any attempt to make those watertight when submerged. That's how little boats sink. The (usually open) companionway just makes the end part happen a little quicker, but it's all over by the time a companionway gets near water in most trailerable boats.

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Mea Culpa.

 

Okay, I went back and checked out their website. They DID do more what I'm talking about. I'd still like to see a different rig and cockpit layout but I take it all back.

 

(I told myself this is what I get for skimming an article and whipping out a careless quick response but who would listen?)

 

heh heh heh it's supposed to be ANARCHY dammit! Right?

 

Anyway, I like the boat but don't have that kind o' money for a 30' camp-cruiser no matter how spiffy. I do think it's an evolutionary improvement over previous similar boats, but the cost is much too much. Ironically, a lot of home-builders are putting together similar boats that will cost far more than they admit to (although still not 85k$) that are nowhere near as capable under sail.

 

I've only sailed one cat-ketch rig, and that was OK but not great... it's much less work to rig than a sloop can be; if you don't lose too much performance (a matter of personal taste) then it's a net plus for a trailerable...

 

FB- Doug

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

 

 

You are almost on the money....after Hoyt did the Freedom 40 Lexcen did a thing called the Revolution 38 ? 39 ? which was <cough> somewhat inspired by the F40. . It was not exactly Lexcen's most original work.

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

 

 

You are almost on the money....after Hoyt did the Freedom 40 Lexcen did a thing called the Revolution 38 ? 39 ? which was <cough> somewhat inspired by the F40. . It was not exactly Lexcen's most original work.

 

Nearly bought one many years ago. One or two were lost without a trace round asia.

Had a great layout, more like an old clipper than a yacht.

The masts were glass, not carbon or alloy, really wide, lots of windage.

The bow would not go to windward in a blow, too much windage too far forward.

You even had to tack when motoring to wind in a good blow.

 

There was one here that was rebuilt with a normal sloop rig IIRC.

 

Looked a lot like the Freedoms, do they have the same problem?

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Cant find any Revolutions for sale at the moment, so no pics.

They must be slowly disappearing.

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Yes Olaf there was one in Mosman Bay for many years near the Amateurs with a normal rig and a few other changes, nice looking boat. A pale olive green colour as I recall, always admired it.

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That sounds like it.

 

Not too many were sold so chances are none are still around. They would not point and were s-l-o-w-w.

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An interesting aside. While googling that design, isn't it odd no one has done a book on Ben's designs!!!!

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All in all a good design, given the limitations of the design brief. I was born and raised in Florida and learned to sail in sharpies from men who had learned the trade in working sharpies fishing, oystering and running light cargo on Florida's west coast. These were all essentially day boats, capable of overnighting in a pinch, even the 50 footers. In smaller boats the rig was struck at the end of the day and stowed on deck. The problem of balancing the rig in a breeze is a real one. If greed or necessity impelled you to go to work in more than a stiff breeze, you chose one mast, stepped it in the third mast step at the forward end of the centerboard trunk and sailed away. This should be a one-man job with the carbon fiber masts supplied, if one could persuade the builder to design and build in this option. Also the berths are a few inches too short, but we sleep in the cockpit whenever possible. The off center companionway may be less of a problem than supposed, because a light decked sharpie like this one (5000#) will almost certainly keep her companionway above the water while on her beam ends. Cockpit lockers require a rethink. In a world where a new Shoalsailer goes for half a million, $85K for a cored glass boat with this level of detail doesn't sound out of line.

124_ARRANGEMENT_5AUG09_SH.pdf

124_P_30_SAIL_PLAN_SH_16JUL2009_Model__1_.pdf

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Us guys could not improve this boat at all. Double wishbone rigs are total dogs in terms of sailing performance. Doesn't matter how nice the hull is if it sails like a dog.

 

Anyone out there remember details of the last attempt at this type of boat ? It was late 70's and the result was dreadful. Not the Nonsuch, there was another. Was Ben Lexcen the designer ? I remember two masts and a fat transom with two portholes.

 

It was a Freedom.

Interesting, and how do you explain multiple Bermuda 1-2 wins in a class by such a dog?

 

Search results for boat "Frogg Kiss"

 

You guys have no clue....

 

The only disadvantage of the rig is that the boat loose about 5-7 degrees of pointing ability. It will not point high. However the boat will be able to go to weather when most of sloops give up...

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I usually like Roger's aesthetic, but lord, that cabin is boxy. I wonder if the sail planforms help with the upwind thang, but skinny masts are rumoured to promote flow detachment, esp with all that space twixt spar and luff.

 

That mainmast(?) (mizzenmast?) and companionway is just wrong. Cheek by jowl, no? I just love to touch everyone I'm sailing with. :o

 

That, and here's another freestanding wishbone rig 30er for your consideration-

 

http://www.vgyd.com/Open30CRCK.html

 

Something modern.

 

:wub:

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Man, that thing would be fun ALL DAY LONG!!!

 

Indeed.

 

I do question whether a canting keel is consistent with a drive for simplicity.

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I like that hull but I'm with AMATI on the boxy cabin trunk. Obviiously they were trying to capture every cubic inch of volume they could. But still, a little more shape could have helped.

 

I think the rig is short and short due to the low stability of the shoal draft design. In light air, especially downwind, I think the boat would need a chute of some flavor. Rodger told me he was adding a sprit to his so he could fly a chute.

 

All in all, given the design target, I think the boat came off very well.

I'd have to sail the boat myself to get a feel for the stability characteristics.

The total self tacking aspect of the rig is appealing.

 

A thin white cove stripe would do wonders for this boat.

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I usually like Roger's aesthetic, but lord, that cabin is boxy.

 

Not boxy. "Purposeful."

 

According to the website, this is the 'performance' sail plan. The normal sailplan has triangular sails. I assume they have less area.

 

These raised deck (or no side deck) cabin types are a mixed blessing I think. They give good room inside a boat with a low waist, and the volume is placed where it goes in the water for reserve buoyancy in a knockdown. However, if the crew is at all timid about leaving the cockpit they feel the additional inches of height under their feet, and fewer inches to the boom overhead, very strongly. If you have to handle something at the bow in a seaway, you would be looking for something to hang to.

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Didn't Gary Mull do some sort of Freedom cat ketch design back in the late 70's?

 

It was Gary Hoyt, working with Halsey Herreshof. They started with a 40', but followed up with a 44 and a 35 and maybe others. Called it a "cat ketch" but it was technically a schooner, and pointed just as poorly as any other schooner.

 

The technical distinction here: if the masts are the same size, it's a schooner, not a ketch.

 

IMHO

if the foremast is shorter than the aft mast, its a schooner. if the aft mast is shorter, its a ketch. If they are the same size, its a brig.

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Man, that thing would be fun ALL DAY LONG!!!

 

Indeed.

 

I do question whether a canting keel is consistent with a drive for simplicity.

 

Compared to a centerboard? I would argue that it's a bit harder for the itty bitty crunchy jamming growing things to get inside the swing keel mechanism than it is inside a centerboard case, assuming both were left in the water. much. I think the Mini style swung keel (using tackle) is pretty simple. Esp., if, like Bakewell-White did, you run the swing keel to the cockpit floor.

 

Didn't Herreschoff do one like this that had internal ballast and leeboards? Was it Meadowlark? I've heard somewhere that virtually all the Sea Pearls have stayed or been converted to leeboards. That, and the Selway Fisher folk like to point out that their leeboard sailing canoes win races against the daggerboard canoes as often as not.

 

How about a swing keel with leeboards and two rudders? Make for a cool helm feel. And as far a s simplicity for this idea goes,

 

L/Y=S

 

where L=Leeboards, Y = Yar, S = Simplicity (Few things are more yar than Leeboards, no?)

 

As Mr. Perry likes to say: that's my theory, and I'm sticking by it.

 

:rolleyes:

 

Paul

 

edit- I think if Roger adds sliding seats, you could get more fun stability.

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Compared to a centerboard?

 

From page on the Van Gorkom Moondance Open 30:

 

Less Complicated: The uni-sail has two trimming controls, the sheet and the choker (purchase system on the front of the wish-bone boom that controls both foot and leech tension, not unlike a windsurfer).

 

Additional simplifications have been made to the boat such as replacing the water ballast system with a less cumbersome canting keel arrangement giving the boat a slight performance edge due to the overall increase in righting moment.

 

I can see where the canting keel would be simpler than water ballast if it worked cleanly. My point was that a canting keel seems pretty complicated for a boat in which you chose a cat rig over a sloop in search of simplicity.

 

Phil Bolger designed included a sliding seat in the design of his Black Skimmer leeboard sharpie, but I've never seen a photo of one in use.

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Did the Presto make it to the show in A town?

 

 

The Presto did make it to Annapolis, although the boat wasn't in the show proper. The picture that's currently on the SA front page was taken of the boat sailing out in the harbor during the show.

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Brig?

A brig is two square rigged masts with both masts roughly the same height.

Put fore and aft sails on the Mizzen and it's a brigantine.

 

"Purposeful"?

No, boxy.

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Compared to a centerboard?

 

From page on the Van Gorkom Moondance Open 30:

 

Less Complicated: The uni-sail has two trimming controls, the sheet and the choker (purchase system on the front of the wish-bone boom that controls both foot and leech tension, not unlike a windsurfer).

 

Additional simplifications have been made to the boat such as replacing the water ballast system with a less cumbersome canting keel arrangement giving the boat a slight performance edge due to the overall increase in righting moment.

 

I can see where the canting keel would be simpler than water ballast if it worked cleanly. My point was that a canting keel seems pretty complicated for a boat in which you chose a cat rig over a sloop in search of simplicity.

 

Phil Bolger designed included a sliding seat in the design of his Black Skimmer leeboard sharpie, but I've never seen a photo of one in use.

 

The more I think about it, the more I'm thinking that a ballasted centreboard and a swing keel are about the same level of complexity, assuming both have been engineered well.

 

One goes fore and aft, the other side to side.

 

Am I missing something here Bob?

 

Paul

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I am guessing they haven't built a Moondance 30 yet. When they do, they are going to discover that the wishbone set at that angle is going to allow way too much twist in the main (you want close to none on a large cat boat) unless a vang wire is added to the rig. And when you do that you really need to mind your finite element analysis on the wishbone, cause it is going to load up.

 

A wishbone rig depends on foot tension to control twist. There pretty much isn't any foot tension in a well setting square head cat rig.

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Compared to a centerboard?

 

From page on the Van Gorkom Moondance Open 30:

 

Less Complicated: The uni-sail has two trimming controls, the sheet and the choker (purchase system on the front of the wish-bone boom that controls both foot and leech tension, not unlike a windsurfer).

 

Additional simplifications have been made to the boat such as replacing the water ballast system with a less cumbersome canting keel arrangement giving the boat a slight performance edge due to the overall increase in righting moment.

 

I can see where the canting keel would be simpler than water ballast if it worked cleanly. My point was that a canting keel seems pretty complicated for a boat in which you chose a cat rig over a sloop in search of simplicity.

 

Phil Bolger designed included a sliding seat in the design of his Black Skimmer leeboard sharpie, but I've never seen a photo of one in use.

 

The more I think about it, the more I'm thinking that a ballasted centreboard and a swing keel are about the same level of complexity, assuming both have been engineered well.

 

One goes fore and aft, the other side to side.

 

Am I missing something here Bob?

 

Paul

 

I think the canting keel would still be more complicated even though through the development of the mini's rope and tackle controlled canting is doable. however the canting is useless in the design brief of the martin boat because they are using a moveable keel to achieve shoal draft and beachability something the canting keel can't help with.

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Paul:

I'm with Chester on that. It;s easy to "lock" the top end of the ballasted CB in structure. With a swinf keel you can't lock the top end. Everything depends upon that axle joint.

What do they call that joint? Pivot pin?

 

DDW:

Good point. That is way too much twist for me. The top half of the sail is beam reaching.

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Bob, a square head sail can work very well on a cat rig, but you need something to control the leach tension. On Team Philips they had some robust wishbones and a vang wire (and they were very conservative roaches). On my boat I have a very powerful hydraulic vang on a conventional boom. An 'ordinary' wishbone set at ordinary angles isn't going to do it. I should talk M. Ellis into sending you the file on my boat for your magazine review. I think you would find it entertaining.

 

post-4075-1256929307_thumb.jpg

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Bob, a square head sail can work very well on a cat rig, but you need something to control the leach tension. On Team Philips they had some robust wishbones and a vang wire (and they were very conservative roaches). On my boat I have a very powerful hydraulic vang on a conventional boom. An 'ordinary' wishbone set at ordinary angles isn't going to do it. I should talk M. Ellis into sending you the file on my boat for your magazine review. I think you would find it entertaining.

 

post-4075-1256929307_thumb.jpg

 

DDW, In (I assume) your pic, I can see two telltales, and the bottom one looks like it's stalled a bit- looping to leeward. Unless this is what you've found to to be fast, doesn't it argue for more twist in the middle of the sail?

 

Having raced Finns OK Dinghies and Lasers, it seems that how much twist you need is a movable feast.

 

And my experience with square head windsurfer sails is that they are more efficient when twisted, mainly to control the head vortex. The telltales in the Presto pic, what you can see of them, look ok. I don't see any luffing. IIRR, Presto has North Sails (tm!), and they do design both Finn and Windsurfer sails. Roachy pinheads seem to like less twist, unless tapered and swept. I stare at one a lot, with and without a jib.

 

Back in my Div. II windsurfer days, I experimented with a vang. The most succesful went from the end of the wishbone to the foot of the sail. It did distort the wishbone, but installing a line between the two arms of the wishbone that passed through a big grommet in the sail cured that. No failures in the wishbone arms, the jaws, the clew attachment, or the line securing the jaws to the mast or the mast (as in crushing). Very succesfull in controlling the leach, although I abandoned the idea because I thought the resulting baggyish foot was slow, although Bill Hansen has informed me recently that a full shape down there can be actually a fast shape. Go figger. Some windsurfers tried a bar between the two arms of the wishboom going throught the sail to try to lighten the system as a whole, but was considered too fiddly when rigging. It did work though, and I didn't hear about any failures. I also tried a solid rod beween the end of the wishboom and the sail foot, and it was really promising (at least on land), but would have required a turnbuckle to adjust, and was almost impossible to uphaul. a couple of others tried it, but it didn't go anywhere that I know of. I suppose, though, you can argue that everything is overbuilt on a windsurfer, and therefore the structural problems are suppressed. Also, since the windsurfer sailor is hanging on to the boom, the whole system can be seen as having a different design dynamic than a freestanding mast. Chris White designed a planing catamaran (single sail) where he supported the jaws of it's wishbone with 2 spars from the front (ish) tof the hulls that I always assumed was a way to get around the design conflict that the freestanding mast, and I imagine a stayed mast also present(s). IIRR, the sheet on the White catamaran came from the outside of the hulls, and that was kind of the same angle that you hang on to the boom of a windsurfer. Herreschoff tried kind of the same idea on a pretty big scale (in CSoYD). Said it was an engineering and construction nightmare.

 

Bob, fair enough. Wasn't there a German design with 2 swing keels that swung them out to each side to get the thing shallow enough for beaching? Not very simple though. I suppose you could swing a single swing keel all the way up to one side to get shallow draft if it didn't capsize the boat. I'm reaching though a bit with that methinks. Hook it from above and tie it off. Everyone sit on the opposite side until the bulb was resting on the beach. (heh heh)

 

Paul

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Amati,

 

I am not going to claim the trim in my picture is great. That was taken on about the 3rd day out with the rig.

 

First of all, a large cat rig differs in one important detail than a small one: it is large. While that seems trivial, it has important consequences regarding twist. A small rig like a windsurfer or Fin is operating in a very steep part of the wind gradient. If you look at any of the published curves, you will see a very steep gradient from zero to 10 or 15 feet, flattening out quite a bit above that. The actual gradient of course depends on atmospheric conditions and sea state, and can vary quite a little. But in most cases the effect is much more pronounced near the ground. A windsurfer or Fin operates in this area, with the foot 2-3 feet high and the head at 15 feet or so. On a large rig like mine, the foot is at 10 ft and the head at 65 ft. The gradient is much less pronounced, therefore the need for twist to accommodate it is far less.

 

Second, with a real square head sail, the lift distribution is already pretty good (for minimum drag) without much (or any) twist. On a triangular sail, some twist can make up for the poor planform and produce lower drag than an untwisted sail. This is obfuscated a great deal on a fractional sloop, since you have a much more complicated slotted configuration. The slot does not go full span, and allows larger angles of attack in the lower sections (where the effect of the jib and slot are greatest) without stalling. So you often see lots of twist in a square head fractional sloop, but effectively the airfoil (main and jib together) has less aerodynamic twist than it might appear. A cat is very simple by comparison, very much like a simple wing.

 

I theorized all of this prior to sailing with the rig, but it can now be demonstrated to be correct. Now back to the picture. Since that was taken I have released the slides holding the stack pack to the foot, as it was making the foot too flat (notice the funny reflex in the stackpack batten). Also we have added a stripe of tell tales just below the first batten. In anything but very light air, to get all the leach streamers flying and the other tell tales unseparated, I have to harden the vang to eliminate as much twist as possible. Flow separates near the mast low on the sail first, then reaches all the way back to the leach before it gets up to about midspan. Trim is quite critical, there is only about a 2-3 deg window of angle of attack when everything is just right. Since whole rig rotates, bearing away is just a matter of turning the hull under the rig, the trim problem remains the same. The difference is as you bear away, drag becomes less and less important, so overtrimming to stall seems to have less and less effect on boat speed. It can be fairly dramatic upwind however. In the picture, the lowest leach streamer is stalled, if there were one below that it would be more so. What is needed in that picture is a harder vang (for less twist) and an eased sheet (for less angle of attack at the boom).

 

On the picture of the Presto, the leach tell tales are flying, but they are all up at the top. I can virtually guarantee that the lower half of that sail (at least the foresail) is well and truly stalled. The Presto is again more complicated, having a tandem airfoil. But if you look at the Windex, they are practically beam reaching, and have the wishbones well in to do it. Compare that with the Windex in my picture, which you can just make out at the masthead (and my Windex rotates with the mast...). In my picture, the top 3 battens (ignoring the diagonal for the squarehead) are all about the same angle of attack, the fourth down is a bit more angle and is stalled, the fifth is nicely stalled. Even so, they are probably less than 5 degrees different. In the Presto picture, it looks like there is 45 degrees or more difference between the top batten and the lowest one.

 

I'm not picking on the Presto which I think is a very interesting little boat. Its just that the square head concentrates all of the sail forces between head and clew, and a wishbone has a hard time with that. On my rig, the vang is designed to produce 4000 lbs of downward clew load. With my current halyard setup, I cannot get to that because it stretches the halyard and drops the head of the sail, putting scallops in the luff. However with everything as tight as I can get it, once the vang is on and we are trimmed up hard on the wind, I can go forward and pull the tack ring by hand and unload the tack car - there is that little load on it. This is a 960 sq ft sail. On a wishbone, the only force able to produce leach tension is the foot of the sail reacted at the tack (if we ignore a small amount supplied by the sheet), pulling the wishbone down. So the on a square head, the sail twists. If on the Moondance they had a very wide traveller, they could get a lot of leach load from the sheet - that's how its done on most sloops after all. There are a couple of problems with that: one is that you do not sheet a cat to near centerline (it isn't operating in the wash of the jig after all); its sheeted more like a genoa would be. So the traveller has to be really wide. Second, you are going to give up a lot of efficiency as soon as you start the sheet to bear away, now the effectiveness of the sheet and traveller are lost and the sail twists.

 

Wow, didn't mean to run on like that but as you can see it is a subject dear to my heart.

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DDR, I know the feeling: It has to be near and dear to your heart, or else we wouldn't have spent the $$$,$$$.00's to do all this proof of concept.

 

I have a roachy 3/4 rigged ULDB 40er (a Bob Perry design, named Amati, oddly enough), no permanent running back, 100% jib, assym, which I did because of your reasoning above- I figured that twist leads to more forward thrust at some point in the rig, esp if I induce it. I hope to be moving from a roachy pinhead to a more squareheadish main sometime soonish. Also, when you get this high off the water, above 50', you get stronger winds. Put all, this on a hull with a D/L of 96, and have some fun.

 

At what true windspeed do you start to depower? Do you induce twist to depower?

 

Since VGYD was (may still be) in Boston, I figure they have been exposed to Van Dusan, so some experience with WylieCats has accrued, which I hope will rub off on Moondance. The ability to design specific bending characteristics into carbon masts is an amazing thing.

 

I want to be a fan of the Presto powerplant, esp. since Irens has some BIG world cruisers that use the planform, with overlap, no less, and Munk's biplane theory is solid, so the forward sail IS sailing in upwash.

 

One of the crew in the pic of Presto is sitting on the low side, so they have to be depowering at least a little.

 

A small niggle- airplane wings don't fly in a twisted flow, and at least among some designers, zero lift at the outer tips of wings is a strategy for reduced tip vortexes. Also, Finns and Windsurfer masts are more like 20' in the air.

 

I would really encourage you to talk to Bill Larsen (Larsen Aerosports). If you don't know him, he started WindWings windsurfing sails, he's a professor of Physics, and he knows his stuff. He has been designing and making sails for the WylieCat series that Tom Wylie has recommended as improving the performance of the designs. He's doing square headed wishboom rigs.

 

I like wishboom rigs because they are an elegant solution to the catboat question, one that Roger Martin has used in a rig that is, as you pointed out, in the area of greatest gradient twist. Add to this that I have one of Bob's cartoons (named Mac, after our recently departed Westie) on our entry wall of an unstayed catboat that gets me all dreamy eyed. It has a roachy pin head. So I'm not as hard headed as I probably should be about bendy unstayed wishboom cat rigs.

 

Besides, when I'm out single handed, I'd rather sail a sightly inferior rig to her potential, than sail a superior rig in a mediocre way. Nobody might be watching, but I would know. And it would piss me off.

 

Paul

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At what true windspeed do you start to depower? Do you induce twist to depower?

Upwind we are fully powered at 10-12, and wanting to reef at 12-14 (true). I have tried inducing twist to depower, in fact I get twist as the wind increases whether I want it or not. I don't believe it works very well. Sure it depowers, but also adds a lot of drag. That's ok for a few minutes, but not efficient compared to a reefed sail. I have to say the same thing about the mystical ability of the bendy rig to "release pressure" and depower automatically. Yeah I guess it happens to a small extent, but I find the effect relatively small and not of great value. The problem with dynamic pressure is the V squared component: going from 10 to 12 knots is nearly 50% more pressure - that's a lot of depowering required. 10 to 14 knots is 100% more. I have found this carbon rig to be fairly stiff: it does bend, but does not flop about with gusts nearly as much as, for example, my Nonsuch 30 with the aluminum mast.

 

Many of my ideas come from designing and flying hang gliders back when it was dangerous. Hang gliders are interesting because they are flexible membrane wings operating in the same Re range, with one great advantage: unlike sailboat rigs, you can measure the L/D directly and easily. In the early days, a huge jump in performance (2x) was realized by going to what we call a square head planform from pointy tips. Since the lift is fixed that means half the drag. Translated to sailing, 7 degrees improvement in pointing ability.

 

It's true that airplanes don't operate in twisted flow, but this isn't as big an effect as many imagine. Here for example, is a calculation of apparent wind change with height, calculated on gradient data taken at Block Island and published in several sources:

 

post-4075-1256960933_thumb.png

 

Note that the apparent wind difference between 10 ft and 60 is 1.4 degrees. That doesn't call for much twist.

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Paul:

I'm with Chester on that. It;s easy to "lock" the top end of the ballasted CB in structure. With a swinf keel you can't lock the top end. Everything depends upon that axle joint.

What do they call that joint? Pivot pin?

 

I'd call that joint vulnerable when you run aground, and the board had better break before it does. A distinct disadvantage of daggerboards in shallow parts of the world: they have to break away, or something worse will break. Centerboards can kick up. I had a spare daggerboard for my F-27 for that reason. Didn't want to be out of commission waiting for a replacement.

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DDW- The following argument- Bethwaite would agree with the TWS 7K/twist figure because, as he points out, above about TWS 6 K, flow over the earth tends to go more laminar, and therefore the sailor will need less sail twist, but below TWS 6K, flow becomes much more twisted from the sailors point of view, because the flow over the earth's surface is not laminar. More boat speed amplifies this effect, both upwind and downwind. The difference can be huge.

 

Since skiff rigs are predicated on an active rig, I'm going to respectfully disagree with you on the bendy mast concept. It's fiddly to get to work, as my years planing and glueing Bruder masts proves, but when you get it right, :wub: . The Bethwaites have come out with a sportboat using the concept, which is not small. One of my longterm goals with Amati is to develop an active rig. I think the WylieCats are there already, and since Hansen has been developing his compliant leach patent for a while now, I think you're going to see it on larger sails.

 

Tom, since I have a deep keel (8.5'), and I've run aground once, and I've had many boats with centerboards, skegs and daggerboards, it's hard for me to get too excited about the risk/ return on any of them- as far as the ground is concerned, high AR keels are unyielding to the blade or boat structure, daggerboards are unyielding or break the blade or boat structure and leak and jam, centerboards yield, but jam and leak, and are big complex stuctures inside the boat and are draggy nightmares underwater unless you put flaps on the opening underwater, and they tear off, and you have to inspect and replace them over and over, and after you hit something, there's usually a big ding in the leading edge that you have to deal with. Windsurfer skegs even break themselves or the skegbox, sometimes just when spinning out. Leeboards have some structural advantages, and you can inspect them easily, but when the air/water interface gets stressed around them, they become draggy and inneficient. Low aspect keels usually aren't great upwind, and if they are, like in the metre boats, they clear your sinuses downwind. So a swinging keel is more a matter of degree to me, complex like a centerboard, vulnerable like a daggerboard, stressful structually like a high AR keel, needs another blade to make it work well upwind like the Hood boats (or like the VGYD boat, or the CBTF boats)), which brings all the stuff related to centerboards and daggerboards into play. IIRR, there was a swing keel boat that had the top of the keel running on a track inbetween 2 athwartship bulkhead bulheads imbedded in a veritable torsion box below deck, which might be considered locked into the structure, but kiss your interior goodbye. I've seen a mini that had a track on one athwartship bulkhead anchored by two longitudinal members that could be frozen in place by solid braces, but that's just a really complex keel at that point, although pretty secure. Maybe the gear approach used by Herreschoff (CSoYD) for a swing keel has advantages, but I'd hate to strip that sucker out of site of the marina. Tradeoffs tradeoffs. I do Like the way Amati goes upwind (and down) though. :wub::wub: And she didn't leak a drop after being pulled off the rock. Perry and Rander made sure of that.

 

Paul

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DDW- The following argument- Bethwaite would agree with the TWS 7K/twist figure because, as he points out, above about TWS 6 K, flow over the earth tends to go more laminar, and therefore the sailor will need less sail twist, but below TWS 6K, flow becomes much more twisted from the sailors point of view, because the flow over the earth's surface is not laminar. More boat speed amplifies this effect, both upwind and downwind. The difference can be huge.

Amati,

 

I agree that at below 6 knots TWS, things can get very different. Rig aerodynamics get very different too, strange things like laminar separation etc. Of course a typical cruising boat isn't moving very fast under those conditions either. One problem I have is that in very light pressure (<5 kt) I want more twist and can't get it: the weight of the sail alone is enough to tighten the leach too much. Still, this boat moves better in 2-4 knots than most others (literally sailed circles around a small racing fleet one day) due, I think, to lots of sail area held in a pretty rigid airfoil shape by spars and battens, when everyone elses sails were hanging limp.

 

I remain unconvinced on dymamic bendy rigs, Bethwaite notwithstanding. There might be a few seconds a mile in it, enough to give you a 1 boat length win but insignificant to a cruising boat. I am interested in fast average speeds, over a range of conditions, with a very shorthanded crew and a minimum of effort. My continuing belief is that a large, efficient, easily handled rig is the key. Now if you are in a racing class that limits area, then you have to chase any corner you can.

 

One curiousity on the Presto (and Moondance): what do they do for a topping lift? It looks like it is just a conventional lift that is allowed to flop around and chafe on the sail and catch on all the battens during the hoist? That is another disadvantage of the wishbone with a large roach. Sponberg used a rigid vang on Amazon's wishbones which solved this problem as well as leach tension. But at that point, the rig really looks a lot like mine, except on mine the compression elements are straight and therefore more efficient.

 

While I am at it I might as well point out another practical disadvantage of the wishbone for an oceangoing boat: when reefed, there is an uncontrolled bunt of sail below the reefed clew. This is because the reefed clew position moves forward and up the wishbone as you go to deeper reefs. With a large roach (and therefore a more vertical leach) it is less of a problem, but would still be very significant on my boat at the 3rd reef. This sail bunt can create big problems if it fills with water and has led to the loss of a Nonsuch in the North Atlantic.

 

I like wishbones - but like every other decision on a boat, they are a compromise, not without drawbacks.

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On the picture of the Presto, the leach tell tales are flying, but they are all up at the top. I can virtually guarantee that the lower half of that sail (at least the foresail) is well and truly stalled.

 

I wouldn't read too much into these pictures of the Presto. From what I read on the website, this was one of the first few sails of the prototype, and the boat is just reaching back and forth for boatshow purposes.

 

If I read the web site correctly, the boat isn't even properly painted. The gray color is a primer.

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This thread is fun. I was one of crew of builders of the Hurricane Island 30s and have sailed one of them.

 

A change I'd make to the boat to make it suitable for cruising (if anyone were to ask) would be to go to a balanced lug ketch rig with the mizzen slightly smaller and stepped further aft at the aft end of a bridgedeck. Balanced lugs with light booms can be reefed more effectively and easier than a sprit or wishbone rig, and in my experience the boat needed that capability sooner rather than later. (The photo on SA's home page shows quite a sizeable crew to windward in a moderate breeze on reach... more weight than you'd likely have as a cruising family). The sail area could be about the same but lower down. It would probably be a hard sell though. Who'd be comfortable with such an odd look? That rig would also allow for shorter masts. The current masts were a handful to step, especially forward where the deck was narrower, and it was best to get it right the first lift. It wasn't so much the weight as the length and balancing them in the vertical as you lined them up to slide into the partners. An easily set and removable light mizzen staysail on a roller would be great, too.

 

The bridgedeck in the cockpit would allow for a wider and more easily accessible companionway so you could enter the cabin on either side of the rather large centerboard box. If possible I'd also make the rudder lighter, less complex and non-swinging. Just lift it in good time when beaching. The cockpit lockers would benefit from very large freeing ports. I agree with the comment about the boat being at the very top limit of trailering size.

 

But the deck mold investment has been made and we'll see how it goes. Good luck to Union River Boatworks! They are good people.

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If possible I'd also make the rudder lighter, less complex and non-swinging. Just lift it in good time when beaching.

 

That's OK in parts of the world where it's only shallow next to the shore. For Gulf Coast sailors like me, they have to kick up. If you're at all adventurous, you're eventually going to come across shallow water. Having rudders and centerboards kick up prevents damage when you come across it by accident, and allows control when you cross it on purpose.

 

Edit: Wait! That was a newbie, and I didn't say anything rude! Sorry! FONASUYW/GF'sTs! There! Welcome to Sailing Anarchy.

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