Strange double finn

Discussion in 'Sailboats' started by Euler, Jun 18, 2008.

  1. Meanz Beanz
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    Meanz Beanz Boom Doom Gloom Boom

    Better righting moment? Its not uncommon for bilge keelers in these parts to have them quite a bit further inboard. I don't want to argue with you, it is a very simple observation that they are extreme, as for the designers motivation? Mebe it was indeed that simple, that he wanted to dry the boat out, but not having any special powers I will not have a go at that one :D
     
  2. Aethelwulffe
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    Aethelwulffe Junior Member

    Agreed, better righting moment if those keels have any significant ballast to them. I don't know that part either, so the upshot of what I am saying is that I think the keels are at the angles and positions to attempt to get more blade into the water with less draft. He starts them at the highest point he can. This is also easy because he can locate structural support well outboard and integrate it with the upper chine and probably the chainplates. I just am not so sure that he will get much more effect out of the larger blades where they are than he would with an equal draft with them under the lower chine. I think "extreme" (not a word or point that I am arguing at all) in this case may be synonymous with "boondoggle". It may very much be that these pictures do not do it justice, but It doesn't look like this boat will point so good or have very good course stability. Seems designed around some not-so-well thought out presumptions. I am pretty darn sure that if this boat goes high and dry, you would not have to sweat it if she was on a bit of an incline. Sure saves on boat stands.
    If someone had never built a bilge-keeler, and were building a hard-chine developed panel boat, there might be some paranoia associated with it tipping over with one fin on a rock and the other in some mud...and a fella might just come up with something like this, draft requirements or no.

    Advantages/construction advantages:
    1. Keels are well supported, and can tie in with the chain-plates.
    2. Lots of blade in the water, using the draft of the hull in addition to a bit more for some fin (shoal draft).
    3. Effective bilge keeler (inarguably).
    4. Looks sporty to the right crowd (Earth Humans).

    Disadvantages:
    1. Keels get pressure from hull. Might be offset enough to make a good blade on the leeward side, but overall not as effective as a centerline keel for a given wetted area.
    2. Windward blade might provide undesirable lift.
    3. Added drag.
    4. Twice the cost.
    5. A total disaster in areas thick with lobster pots....
    6. Bad docking control
    7. Long rudder response time (larger arc of travel).
    8. Ugly or suspicious-looking to many Ubermenchen (sailors).
    9. Will bang in a chop like the outhouse door in a gale.

    Anyone care to discuss this or add to it?
     
  3. rwatson
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    rwatson Senior Member

    I havnt discussed that option with the designer, though I do know what you mean. Certainly the twin boards have been discussed in detail - there is some optimising to do there with regards to 'toe-in', reducing drag while beating.

    I am trying to talk him in to building in 'variable geometery' capabilities for the daggerboards so that I can alter the attack angle by 5 degrees or so like many racing boats can.

    RonR
    re rudders extended from hull - instinct indicates that it should make them more effective, as some racing dinghys do. You might also think about 'gates' about 4 inches below the waterline (like the fins on the outboard) to prevent ventilation and cavitition. If you made the extensions right, you would have a great boarding ladder too :)

    Re Aethelwulffe coments -
    "How is an outboard *ever* a good tradeoff for anything ?:rolleyes: :p "
    I dont know how you had problems with "keeping the outboard in the water" in a 20 knot breeze. I have been out on my mac in higher winds and considerable chop, and except for the odd engine 'race' on a really big swell, there were never any problems.

    I can give you a million reasons for a decent outboard , here are a small selection -
    1) Getting back to the launching ramp about 30 minutes before all the other sods out for a sail on a nice afternoon
    44) Chasing and catching the forty footer who just failed to 'give way' to lob a toilet roll onto the helmsman
    45) Avoiding the steel forty footer who failed to 'give way' and had a toilet roll lobbed at the helmsman.
    67) Manouvering around crowded marinas looking for the berth you booked, in high winds.
    102) Getting in to the jetty before dark after the wind died and left you out at sea.
    103) Charging up the batteries for the nav Lights when you didnt get back before dark
    206) Getting out of the way of the car feighter doing 15 knots in the shipping channel, blocking the last of the fickle wind, against a strong tide.
    etc etc

    "That speed does you absolutely no good when it gets too rough to use it"
    Of course it doesnt - who would speed in a severe chop??? But in really rough weather, against the wind and tide, I would rather have 50hp than the piddling 15 that most auxiliaries are - especially when I have my family on board.

    "As far as a water-ballast trailer boat, I cannot see why anyone would want to ever go sailing in something that has a ballast density of 1:1"

    I dont understand why?. It works very well, is free, and at least I can pour it down the slipway instead of having to cart it 250 kilometres up the coast, on an expensive 3 wheeled trailer. And when I get up the coast, there is an unlimited amount of it to pour back in when I re-launch.
    Also, on my project, most of it will be drinkable (in an interior bladder) for that extended seaside stay - all 400 litres!. I will be able to shower in it.
    That same flat bottom you are not keen on, combined with the roomy interior and water ballast, makes a damn stable platform - and a lot less tippy than quite a few 'proper' yachts.

    Its easy to swap stories about 'boat disasters' - Macs dont feature in a lot of them, so they are always food for a lot of talk because they are so rare.
    Check out the 'Keels and keels' again thread for a bit of 'proper boat' disaster talk.
    'Proper boats' *will* perform better in severe conditions - and if you are a masochist, feel free to enjoy the severe conditions! I will be safe in the carpark, or on my way up the freeway to sunnier climes.

    I have done my time on 'proper boats', and all the best times were in great weather on the mac. Smashing into 10 ft waves in the cold southern ocean is just rubbish!
     
  4. Meanz Beanz
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    Meanz Beanz Boom Doom Gloom Boom

    Young (NZ) did some quite successful water ballasted trailer sailers if I remember rightly.
     
  5. Meanz Beanz
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    Meanz Beanz Boom Doom Gloom Boom

    I believe that if you project a line from the rudders pivot point at the water line to the center of the boat at the bow(s) (also at the waterline) you get the line/angle that the tillers should follow. I saw a diagram of them working it out for a go-carts steering, similar approach (no waterline :D)... seems it applies to anything with steering controls that are set apart.

    Its probably not a really big issue on a mono but it would decrease drag through a turn and its easy enough to do if building from new. I'd guess it also gives a little more room at the blunt end of the cockpit... I must look more closely next time I see a twin ruddered mono!

    Cheers
    MBz
     
  6. Aethelwulffe
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    Aethelwulffe Junior Member

    Decent outboard...hmmmm.

    I tossed out the fighting words with smilies...I hoped you noticed. As far as "most boats having a 15" Most boats that now have a 15 used to have a 6 or an 8, and they still did hull speed. What's more they were not squatting on their lines. Unless their boat is a planing hull form, the extra horsepower does nothing for them. They have some idea that it helps them to power through this or that or it helps in a current....none of which math supports. You have a hullform that planes easily though, right? Those hull forms should be kept within easy reach of dirt as you said. Even then, they are rough and beat you up after a full day. Most folks do not get a boat with dreams of ICW sailing- though granted that is what they do. Most folks do not go sailing with the idea that they will be tossing toilet paper into the cockpits of *******s. (By the way, use some of the gasoline and a lighter on the next roll, with a bit hanging off for a fuse...works great). Most folks know that is what flare-guns or a 30.06 is for. Otherwise you should always be a gentleman on the water, not raising wakes of your own. Later, bring some scuba gear and a brace and bit for the 90' sportfisherman.
    Flat bottom is really stable hunh? why perhaps I shall saw off the bottom of my Freindship sloop and cross-plank her. Heh, I think not. Good ballast ratios at a good draft is stable. Flat bottoms FEEL stable in stable conditions. Hey, I am not arguing the stupid "proper boat" angle here form the usual perspective. If you want to get to that, I can disqualify 99 percent of the boats in every marina around the world. A "Proper Boat" as I am sure most of the clientel around here agrees is one that tries to be one kind of boat. A sharpie or skiff for the flats, Lead and a short stick for offshore, -all that. Motorsailers are not 50/50 boats, they are 20/20 boats. They neither sail nor motor well. As for water ballast, you can't lower your CG very much. You have the end result of a boat with a much shallower draft and a much much lower displacement while creating more wetted surface. The math doesn't give such great results. This idea is not new, but it has only been considered seriously since offshore raceboats have started using WB tanks integrated with ballast stablizers. These systems bring some inherent dangers, as they pump the ballast to the windward side, and must shift it before tacking. This is in combination with simply massive lead ballast bulbs on obscenely deep fin keels. That set the stage to sell the idea however in the minds of joe average. This is very very different from what water ballasted trailer sailers are doing. I would stack up an open 26' unballasted CB dory or sharpie against any water ballasted boat in any conditions you may care to put them in. I think that the centerboarder will out perform them, and feel at least as stable. Water ballast does not provide any added stability...at all... until the ballast is shifted significantly to one side or the other. It also requires complex (and therefore undepndable) systems. You need juice and pumps for operation of the primary system: the hull. That is one system I would prefer to just work on it's own.
     
    Last edited: Jul 3, 2008
  7. rwatson
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    rwatson Senior Member

    Hi Aethelwulffe

    A bit slow in replying, but no fighting words intended. I notice you didnt specifically address most of the points I raised, from light trailering to more speed on the water - maybe they arn't on your list of priorities, which is fair enough.

    But I still say, a flat bottom *is* more stable. I have moored next to a 40 foot ocean racer in a marina that did 8-10 degree rolls in the incoming swell, while my Mac barely moved 3 degrees with a belly full of water. Guess who slept the best that night. And whats more, he was paying marina fees for the next 6 months, while I had free parking in the front yard at home.

    Water ballast works fine without pumps to move it. There are no pumps an a Mac. And I would be happy to bet good money that the dory with the centreboard is a lot less stable than a water ballasted equivalent, but I bet it cant get its steel centreboard up with one hand on a line. Chicks hate 5 minutes on the end of winch handle!

    But the best thing you said was - petrol on the toilet roll! Boy, am I going to remember that one. I dont smoke, but I will be taking a lighter out next time :)
     
    Last edited: Jul 28, 2008
  8. Aethelwulffe
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    Aethelwulffe Junior Member

    Well, I didn't really notice you bringing up points that were substantiated with anything like math. The opposite really. You can refute and counterpoint statements when the reasoning behind them is mathematically or otherwise demonstrably testable and the data to support that claim is presented or cited. I have not identified anything in your statements that has not already been hashed out here in those terms. Water ballast can lower the CG of a vessel, but only at an extreme cost in interior space. It does not give positive ballast displacement...at all. You sink the boat to the level you want it riding in the water. Large cargo ships do this to lower their CG, and gain efficiency at certain speeds due to displacement length. Smaller vessels really and truely operate in an environment that has a very different fluid properties and a very diffent relative environment. We have discussed this to a length, and no new data has come up...we have only seen some defensive reactions from a single Macgregor owner.
    Lets filter some counterpoints just to make argument....for funsies.

    As far as a dory, or flat bottomed boats, who said anything about a steel centerboard? I was referring to an unballasted wood dory. Generally, even a steel centerboard IS directly raised by hand anywho. That is a prospect I would rather face rather than pumping by hand. Your other reference was a "40' ocean racer" of unidentified quality (I somehow doubt you were talking about anything I would refer to as a race boat, and certianly not a whitbread or anything like) is very likely a canoe hull with a low b/h ratio fin keel on it. Those vessels are essintially flat bottomed boats with a radius chine. If that vessels was bobbing about visually and you seemed stable, great. I would challenge you to anchor your vessel on a breaking sea and sleep the night away from the marina. Then put you self on an old channel cutter or a friendship, or a star or anything with a full keel and spend the same night. You need to up the board and run the macgregor onto the beach to get a better night's sleep. Then you need good mosquito nets.
    Flat bottoms are not "more stable". They have better initial stability than a canoe hull fin with equal ballast, but a full keel full displacement generaly has better dockside stability. Out in chop, the ride on the flat bottom is too rough to worry about whether you have less initial tenderness. The stability issue with a flat bottom sailing craft is a different kind of stability problem. First, as you build speed, the hull must plane to achieve any sort of efficiency. This is fine for people that want to motor about in a state of stink and waste, but not great for sailing a ballasted and overweight boat (though just fine for a very narrow unballasted and very light boat like a sharpie or a boardboat). This is obvious as you put out of the marina, and even more obvious as you start sailing. Flat bottom boats (to a slightly less degree a radius chine such as your M26) develop a rather asymetrical footprint as they heel. This makes them harder to steer, and therefore less stable. In heavy quartering seas such as you will find when entering shallow waters to a typical inlet along the Florida coast are MUCH less easy to ride in a canoe hull than a full keel. Any boat that tends to surf is quite dangerous at this point as well. For a motor boat (operating unballasted) the M26 has a VERY HIGH CG. That is just the point I would expect lots of people to start the engine and attempt to run her in. Whats more, the large engines create far too much weight aft. You cannot make a valid supporting argument for a positive quality of having an outboard hanging off the rear, under sail or power, it is a disadvantageous location in terms of stability.
    A decent, forgiving review of the boat can be found here: http://www.practical-sailor.com/boatreviews/macGregor-26-boat-review.html

    Superior stability is not noted as an advantage. Slower righting arm (much) and a defined limit of stability (115 degrees) that is easily achieved in a surfing broach.

    I postulate that the same trailerability, and greater stability (safety of the crew and speed under heavier conditions can be found in a boardboat.
     
  9. rwatson
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    rwatson Senior Member

    I am really not sure I can digest all the points you are making here. I will just try pick out the gist of things I think you are getting at.

    1) "Water ballast can lower the CG of a vessel, but only at an extreme cost in interior space."
    I have been in lots of trailer sailers, and I defy you to quote one of the same length and beam as a mac with more interior room. As a 6foot+ I couldnt even stand up in Hunters and a lot of similar boats.

    2) You seem worried about the boats stability, and want figures.
    Re the math - I have posted a copy of my recently calculated stability calcs from the NA for my next project, a 28ft, water ballasted trailer sailer with 500kilos of water, and 150 kilos of permanent ballast. You will note a positive righting effect through to 120 degrees, and very high righting moment to over 60 degrees. All this with no lead keel.

    check out http://www.boatdesign.com/postings/pages/knockdown.htm
    for stability curves for a perfectly flat bottom boat with no ballast. Even at 90degrees, it has 2000 lbs of righting moment.

    To quote the author "In fact, at a little before 45 degrees heel, the righting arm reverses (which is stated in negative numbers), and it's at about this point that the ballast weight and/or heavy bottom begins to come into play to bring the boat back upright."

    2a) "I postulate that the same trailerability, and greater stability (safety of the crew and speed under heavier conditions can be found in a *unballasted with no steel centreboard* boardboat."
    Well, I would be interested to hear from a NA who will support your view, and I tender the previous paragraph to support my view.

    3) It wont survive extreme rough weather
    I dont believe that I ever conveyed this intention intention to spend a night on the vessel on a breaking sea. I also said smashing through 10 foot waves was 'rubbish'. In fact I think I said that the big motor was to minimise the chance of being caught out in it. But in that unfortunate event, I will turn my boat into a heavily ballaster cruiser, and unlike the Mac, will be able to navigate my way carefully to safety from inside the cabin, with sufficient horespower available to run before waves (the best way of avoiding them, as anyone coming over a sandbar will know) or push carefully through them.

    Out of all the points I raised for the benefits of the 'mac' style of boat, boil down to only
    a) lesser extreme weather performance
    b) lesser extreme weather stability,
    I am satisfied that I have justified my decision admirably.
     

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  10. Aethelwulffe
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    Aethelwulffe Junior Member

    First, I am a Naval Architect. Art Eaton,member of SNAME, Graduate of Texas A&M @ Galveston, BS Maritime Systems Engineering. Member of the SNAME Control Committee for Small Craft Design Volume, and CEO of my own little business Tradition Boatwrights of Tampa Florida. Professional Engineer State of Florida License Number 19939. I am not offering creditials to attempt to dispute any observations you are making about your own vessel, nor am I attempting in any way to disparage your choice of boat. I am not even knocking Macrgregor himself or his company. Despite his own feelings, he is a "down and dirty" builder, but I respect that. He has gotten an amazing number of people out on the water...a very admirable feat.


    Ah, the gist of the "argument" is that water ballasted boats are no better inshore boats than many unballasted designs carrying far less sail. No reference to "extreme rough weather" was made. You are overstating that. I am referring to "slightly dicy conditions that anyone going outside of the jetties WILL eventually experience".

    My worry with the mac is that while a static test shows righting ability from 115 degrees, the force (and speed)with which it can recover from a 45 degree roll is pretty minimal. That slow recovery means that in a short interval, you get hit again before you can snap back. Broaching on a roller you might find at the end of a jetty is not an unusual situation for a coasta sailor. The cabbage patch at the end of the jetties entering Jacksonville/Mayport, or a bad night here at Egmont Key where the M26 rolled and broke that guy's hip are good examples. If you are bugging in from a daily squall that happens every afternoon during the summer here in Florida, both coasts, under power or no-the wind will beat you. If the seas were 4-5 swells (pretty average) and the wind peaks to 25kts, you will have some 8'-10' combined swells at the end of the jetties. These are most commonly quartering seas anywhere on the East coast. This hullform (canoe body) is pretty hard to keep the seas on your quarter. A swell lifts your rear-end up, and starts your stern swinging, any you have to shove the helm over pretty good to keep your stern into the waves. If you are not quick enough and you surf a bit (common with a planing canoe hull) you can have the wave pass underneath you and be sideways in the trough with no way on. Combined wavesets bring very short wave intervals. This is a real good place to experince a broach, as most folks do not have much experience sailing in conditions like that, and the sudden difference scares the crap out of them. My old Chrysler used to handle like that, but she also had a load of iron on a swing keel that kept her upright quite nicely. My J-24 had a somewhat squirrely butt in those conditions too, but was a pretty stiff boat. With low/equal density ballast located within a canoe hull, dispersed far forward as well as far aft of the beam, with the addition of a cockpit full of people and a 50-70 hp outboard hanging off the stern, the vessel would not be in a good situation. The formentioned j-boat, if it broached in those conditions and had excess sail might go over. It would self right, but after it took on water, it would probably sink as they usually have no flotation (mine did)and an open companionway. Some boats can recover from this. A water ballasted boat would very likely roll again and again and again.
    So not all boats are equal, and most are a compromise. Why do I have a problem with this? Well, the M26 looks like a big boat. It has not just one but two sportfish derived ray-ban looking windshield wraparounds on it's bleach-bottle looking self, and a very high freeboard. The folks that buy something that looks like that (observed from the service provider's point of view from dealing with them) is that if they pay good money, it should live up to expectations. Unfortunatly, it is a boat that looks big and capable to their eyes, and has all sorts of positive expectations in the literature, yet it does not perform as well in extreme (COASTAL) conditions as a plywood sharpie might. Coastal conditions are, in my opinion, generaly far more dangerous than offshore. Coastal boats generally just do not need to be as easy on the crew as blue water craft, as the coastal sailors will soon be back in their living room to nurse their wounds.

    I am not pointing at any of this as a reason not to extole the vitures of large water ballasted boats. I am bearing witness that they are not what they are advertized to be.

    Now about your design.....and your stability study...
    Plyboats is a program that produces a semblance (not fully in the modern sense) of a 3-d model. It is an old DOS program that came on a single 1.44mb floppie disk. It is pretty decent for a number of things. It is NOT a design analysis tool. It is not even close to being a virtual water tank. It is massively oversimplified and inherently inaccurate in what it does. It does not even give you the ability to add rigging loads, adjust mass density distribution, bouyancy gradients of sections or anything of the like. The numbers generated by that program are pretty much useless for determining performace in any way.

    You want to get some real cheap test data to back up what geometry tells you?

    Test boats:
    Subject 1:
    Make a box with a 6-2-1 ratio with a false bottom that you can fill with whatever desired proportion of water ballast. Mostly enclose the top, but leave some holes here and there for water to come in a bit as the box rolls over. Add some styrofoam peanuts for your floation. Attach a big lead sinker to the middle of one end to represent an outboard motor.
    Subject 2:
    Take a cylinder of 6L-2d ratio. Glue a stir stick half as long as the cylinders d measure to the middle of one side. Attach a lead weight that masses half of what the water in the box ballast masses to the end of the stick. Attach a sinker the same as used to represent the outboard to the inside of the cylinder where the stick is glued on.

    Control Subject 1
    6-2-1 ratio box with some holes in the "upper" side.
    Control subject 2
    6-2 ratio cylinder with some holes on one side.

    Play with them in the bathtub. Attach rigs to them and play some more. Take them to the beach and put them in the surf. Make observations.

    Predictions: The ballasted cylinder is immune to the damage you can inflict in the bathtub, where the water ballasted box is not. At the beach, the unballasted box does better than the ballasted box. The unballasted cylinder takes on some water, but makes it in every time and doesn't really roll until it hits the land. The boxes both experience much more violent motion.

    ON-THE-TOPIC experiment....What if we put bilge keels on one of the experiment subjects?
     
    Last edited: Jul 29, 2008
  11. rwatson
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    rwatson Senior Member

    Before I research all the other points, here are just two points to be going on with, while ignoring your latest 'out' clause, "unballasted designs carrying far less sail", how about you defend your quote in detail

    1) "I postulate that the same trailerability, and greater stability (safety of the crew and speed under heavier conditions) can be found in a *unballasted with no steel centreboard* boardboat."

    The bits in * are other conditions you stated in the same email about this generic unballasted boat, I am sure you will agree.

    While doing that, perhaps you can explain why the 'other' NA was incorrect when he said
    "In fact, at a little before 45 degrees heel, the righting arm reverses ......., and it's at about this point that the ballast weight and/or heavy bottom begins to come into play to bring the boat back upright."


    2) Next point you can address is your statement "Water ballast ...... at an extreme cost in interior space" and let me know a design of boat of similar length and width with ballasted keel with significantly more interior room.

    On your final comments, I can think of another even cheaper way of demonstrating the effectiveness of water ballasted boats like the Mac.
    Number of boats sold (the top seller in its class for the last 5 years) / the number of capsizes occurring with ballast in them.
    Production figures 7500/???5 ??, about 0.066 - not even 1 percent. Your story is the only one I have heard of in 7 years, so 5 is being generous.

    I would bet I could find more stories of long lead keels falling off boats in this web site alone than the number of turtled macs in the whole world.

    So why would I want to cart half a tonne of lead around on an alternate design, with all the launching headaches of larger keels, more vehicle wear and petrol bills?

    At this rate, we should be qualified as politicians in a few months :)
     

  12. Aethelwulffe
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    Aethelwulffe Junior Member

    First, you are not quoting me directly...and you are skewing the context or making my statements slightly more extreme and unqualified in your posts. please quote me directly rather than paraphrasing and calling it a quote. I am an Americano, and we spell it "centerboard"
    Steel centerboard does not often qualify as ballast. Generally, only a few small fiberglass boats have steel centerboards, being the Finn class for one. Swing Keel boats on the other hand, are certainly ballasted and are often quite stiff. What we are talking about here is that Boardboats, that is to say boats that do not carry ballast but do carry floatation, are potentially better survivors than a water ballasted boat. This is quite true. As a boardboat goes over, and starts riding up on one rail, almost the whole boat is out of the water and up at an angle. The mass of the boat itself has significant righting power if the rig is slacked. If the boat is going over due to overcanvassing, she might stay over. If that is not the case, wave action, even pretty extreme action will not often tip over the boat, but will merely knock it around. From riding around in surf-launched Finns, JY-16's and Tradition 18's, I have found that them being "corky" keeps them pretty safe, despite the fact that you are risking centerboard and rudder in these conditions. You can also right a fairly large unballasted boat, and if I Mac26 goes over, you will not be doing so. She will STAY THERE. Unballsted boats require less sail area and smaller rigs, another generally accepted design advantage. I thus stated it as another reason why boardboats are probably safer than boats low density with ballast in the hull.
    As to the "quote" from the other NA, he was just stating simple geometric physical facts. A ballasted keel gives righting moment much earlier than water ballast. Read the interview with the designer of your boat that I posted to go over the particulars of this. The gist is that as far as your sailing rig is concerned, you ARE a boardboat. With the slow righting moment your boat has (sorry, but a chunk of ballast on a lever is FAR superior than ballast without a lever) it is possible to be heeled, swamped, then heeled again in the next waveset before she snaps back. The next step is being rolled. The keelboat would never be put in that situation, and the boardboat would float over the whole issue (even if capsized)

    First, it's called beam, not width. The total freeboard, meaning the sheer above keel measurement is the real factor here.

    Let's see....um gosh....lets see, I really don't know of too many other boats that have a freeboard that looks like a Russian apartment building. You see, your boat gets all of it's room by:
    1. Not having a bilge....to quote the designer of the boat "one morning you will wake up ankle deep in water".
    2. Jacking up the freeboard (and the CG again) and giving her some wicked huge windage. MacGregor shifted to a cored deck in this boat because the added weight was killing the design. This is how minimal the stability of this thing is.
    3. (please forgive my acerbic comments in this paragraph) Imagine your boat WITHOUT the ballast tanks. You now have standing headroom for Andre the Giant. This shows how confusing this statement is. In doing some eyeball volume calculations, I would say that you have the same hull volume as a Cape Dory 33, without the interior room of that vessel...not by a long shot. That boat even has an inboard engine... If you start comparing your boat to other shitty boats (read "ones that have completely uninhabitable main decks")of equal length and beam, you will find that your newer catalinas hunters and beneteaus have much nicer interiors. They also have lower freeboards, even though theirs is really quite high.

    Sorry buddy. Your math does not really play out here. First, show me a story of a 5 year old boat that had dropped a keel.
    Second you are trying to state (in an unqualified fashion) that keel boats turtle more often than water ballasted boats....poppycock. Geometry does not support that statement, and neither could statistics.
    http://www.ne-ts.com/ar/ar-407capsize.html

    [​IMG]

    I found five articles related to Macgregors rolling. I have seen it. I have also seen folkis here on Charlie pier busting their *** in a hideous fashion when going forward on the thing while tied to the dock...the topsides are a deathtrap. You cannot go forward safely.
    Upshot, you mention trailering around a half a ton of lead. You mention increased fuel consumption. Well, back to the math, the mass does not eat much fuel, windage does. Your boat has all that. Second, you are trying to trailer a boat of a size that should not be trailered...which is the real waste. Frankly, most folks would be far more comfotable on an open boat with lots of room at about 1/10th the towing mass (and a fraction of the windage) of a Mac 26.
    Defend it all you want. State how many have been sold. I provide witness that my con-artist father made a living off of such consumers for more than 50 years without them ever catching on.
     
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