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Thread: Whisstock design #146: potential keel variations

  1. #36
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    Default Re: Whisstock design #146: potential keel variations

    Right, if you wish to sail on the broads I know about sailing them..

    If you intend river sailing the twin drop or swing boards is NOT the way to go, if for instance you were sailing from Acle bridge to Potter Heigham Bridge that is 3 to 5 hours.... In a head wind that's tacking every thirty seconds to a minute.. I've done that several times, that with a fixed fin and in the Lysander with bilge keels . You'd have terrible problems raising and lowering boards every 30 seconds for that distance..

    Also of course that's a no no for a long keeled boat, for many parts of the broads you'd never tack fast enough to make headway..

    So for me that's a need to go for bilge keels, With 3 ft you would have to tack another 3ft off the bank than a fin keeler or you'd be a ground, but it would still be easily possible.
    Just an amateur bodging away..

  2. #37
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    Default Re: Whisstock design #146: potential keel variations

    Thanks, The Q. Useful information. What about a single board?

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by The Q View Post
    Right, if you wish to sail on the broads I know about sailing them..

    If you intend river sailing the twin drop or swing boards is NOT the way to go, if for instance you were sailing from Acle bridge to Potter Heigham Bridge that is 3 to 5 hours.... In a head wind that's tacking every thirty seconds to a minute.. I've done that several times, that with a fixed fin and in the Lysander with bilge keels . You'd have terrible problems raising and lowering boards every 30 seconds for that distance..

    Also of course that's a no no for a long keeled boat, for many parts of the broads you'd never tack fast enough to make headway..

    So for me that's a need to go for bilge keels, With 3 ft you would have to tack another 3ft off the bank than a fin keeler or you'd be a ground, but it would still be easily possible.
    Shirley, if short tacking you would leave twin boards partly or fully down? Not be hauling them up and down. A single offset just allows you get closer to one bank than the other, so cancels out?
    Just musing..

  4. #39
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    Default Re: Whisstock design #146: potential keel variations

    Most Eun Mara owners leave them both down, but we're talking about fairly heavy boards using mechanical advantage to raise and lower.
    Steve

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    Default Re: Whisstock design #146: potential keel variations

    Single board about 300mm or so off centreline. Problem solved. No centrecase. No problem tacking on the broads or anywhere else for that matter.

    Cheers -- George
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    Default Re: Whisstock design #146: potential keel variations

    Yep, that's where I'm heading, I think. I spoke to a friend of mine this evening, the most experienced sailor I know (and he's built probably 25 boats in his life), and he said pretty unequivocably "off set the board. Makes not a jot of difference to performance". When I said I was building a boat he said "at last. It's taken you 30 years too long to come around to it....."

  7. #42
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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Andrew2 View Post
    Shirley, if short tacking you would leave twin boards partly or fully down? Not be hauling them up and down. A single offset just allows you get closer to one bank than the other, so cancels out?
    Just musing..
    If you have twin boards, they are normally asymmetric, which on leaving down / partly down will create a lot of extra drag as they fight each other. Two half up boards going to windward, are nowhere near as efficient as a single full board to windward. Aspect ratio is very very important in keel design...

    No, the offset board won't balance out on river sailing, on the broads you normally sail up to the river bank and almost brush the reeds as you tack. So you can do that still one side with an off set board, if you have to stand off that foot the other side you've lost that foot, not significant on a equal tack but...

    More importantly, is creeping a bank, hard on the wind, especially against the tide, if you have to stand off that foot on that tack it will make a difference..

    Most of the time the rivers here won't force you to stand off, except for a small section or two where I sail / race regularly , a dinghy with the same depth of board can brush the bank the same as a 40ft sailing cruiser, but the cruisers keel could be 3ft more away from the bank..

    Note, that most drop board dinghies and fixed keel Broads cruisers have a similar draft, that is 3 to 4 ft, it's just the cruisers have much more area of keel.

    A single Board,
    Getting my head around the 3D effect of the keel centre of resistance not being in it's normal place, compared to the centre of effort of the sails is a bit complicated.

    Down wind you have the off centre drag, unless you lift the board,

    Upwind, drag will turn the boat up to the wind, if the board is that side, or down away from the wind if it's the other.
    So on one tack the boat should perform better, so choosing the side to fit the board could make a great difference to sailing on your favoured river and it's normal wind direction..

    There is another odd effect, A normal low performance aircraft "hangs" from it's wings or has significant Dihedral if above. A high performance aircraft has it's wings centrally mounted. " Hanging" the body gives more stability, so similar to that, an off center keel should mean a very slightly more hull stability on one tack than on the other..

    I do worry if it's not a problem then why do small cabin sailing boats not do it to routinely to clear the floor area..

    If you have a long keel as well, it probably won't make much difference , But a long keeler isn't really any good for river sailing.

    Constructionally it's interesting too, a normal centreboard case is braced both sides to the hull, an off centre board with a companionway one side means the struts to the hull have to resist compression and tension.


    Note, I'm not a naval Architect, but have designed my own little 16ft sailing boat. I spent hours and hours and hours researching keels, reading learned articles on keels etc..

    Then I had to ignore some of it because for best performance / range of sailing areas in a fixed keel boat on the broads you are really limited to 3ft Draft. The biggest sailing cruisers with 4ft Draft or slightly more, sail on the broads, not the rivers and are towed / motored between events.

    Broads boats with fixed keels just can't have high aspect ratio Keels due to draft problems, we often leave a brown trail of mud in the water on Black Horse Broad as we disturb the thin mud at the start of a season...
    Just an amateur bodging away..

  8. #43
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    Default Re: Whisstock design #146: potential keel variations

    That's really interesting, The Q, and thanks for it. All part of my education.

    However, I am very much at the other end of the experience graph from you. Getting a tack timed right to get me within 5 or 6 feet of a bank I would probably count as something of a triumph! A centreboard 300mm off centre wouldn't make any noticeable difference to me for a while at least because I have nothing to compare it with. Most of my sailing was decades ago in Hoby Cats, available for hire on most popular Australian beaches in the 1970s and 80s. Turning on a sixpence with one of those generally resulted in face-planting into the sail as you both hurtled towards the surf.....again. I don't expect to be testing any new boats limits, at least for a good long time.

    Have you seen the drawings of the 146? Here is the longitudinal section. It has a long but shallow central keel with a chunk of that made up of a lead ballast keel. I'd be interested in your thoughts, in light of your comments about long keels and river sailing. I don't expect to do more than a week a year in the Broads, so that my wife, who gets sea sick in the bath, can have a ride on a boat without too much discomfort. Being perfect for the Broads isn't critical, therefore, as most of my sailing will be in the estuaries of Suffolk and Essex. Heaven forfend, I might even get over to north Kent one day if feeling really brave. I can imagine, therefore, that much as I'd like to sail everywhere, if we did have an upwind river journey to do which involved endless tacking that the outboard-in-a-well would cease to be just ballast.
    Last edited by Mike-in-Suffolk; 09-09-2021 at 07:49 AM.

  9. #44
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    Default Re: Whisstock design #146: potential keel variations

    I enjoy a good intellectual discussion as much as anybody...but...

    In this case I think you are throwing up unnecessary roadblocks for yourself. Sailors have been living with centerboards for a long long time, working around them isn't nearly as bad as you think. Get your hands on a good boat, go sailing, decide if you really like sailing.

    Still with me? OK. Do you want to build a boat or go sailing? Based on what I've seen here over the years it takes 3 to 10 (or more) years for the average WBF'er to complete a build. Are you willing to spend that much time (and pounds/euros) working on an unproven design?
    Steve

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by stromborg View Post
    I enjoy a good intellectual discussion as much as anybody...but...
    .... Based on what I've seen here over the years it takes 3 to 10 (or more) years for the average WBF'er to complete a build. Are you willing to spend that much time (and pounds/euros) working on an unproven design?
    You are probably right about the time it takes but I take serious issue with "unproven design"!

    I've been building and designing sailboats for 59 years now; and a few motor yachts too. Until 1990 I was designing and building one-off custom sailboats in the 35' - 70' range; from then on I concentrated on design work, though I project managed quite a few builds both in wood-epoxy and aluminium alloy – boats like the wood-epoxy Sapphire 27' or the Selestra 67' (five of which have been built, one professionally, two by amateurs and two by managed build).

    While this particular design may not be the most popular of my current designs, they have been built and are certainly not unproven. And the design it was based on remains one of our most popular.

    Just because a builder doesn't care to put their build on this forum, doesn't mean the boats aren't being built. For example, there are eight Design #165's (a bigger sister to this design) that I know of currently in build (and probably many more) – none of which ever feature on this or any other forums as far as I know.

    George
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    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    Steve,
    Mike is interested in building (as we all are here?) and is an experienced woodworker, so has a head start.
    As for an unproven design?? You might want to take that up with George... Moving the platecase off centre is hardly going to alter a design that has been built often.
    Sailing/building: I have just been offered a perfectly good GRP 20ft cruiser (actually, it has a stuck plate..) for free. Am I about to stop building my smaller cruiser? Nope. If going sailing, I have my faering, though someone expressed an interest in that yesterday.

    OOPs, crossed with George.

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    Default Re: Whisstock design #146: potential keel variations

    George, I apologize for casting aspersions on your design work. That comment wasn't directed at you but I can see how it might be interpreted that way. Sorry about that.

    I still think Mike ought to get some time on the water, get the experience he keeps talking about lacking before diving into a build. Unless what he really wants to do is build a boat. I get that, in the last 10 years I've built 4 sailboats boats and a house.
    Steve

    If you would have a good boat, be a good guy when you build her - honest, careful, patient, strong.
    H.A. Calahan

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by stromborg View Post
    ......Do you want to build a boat or go sailing?....
    Primarily, build a boat. I'm a life long woodworker, dabbled with being a professional cabinet maker, and I'm just starting to run low on projects around here. Building the boat is most definitely the primary motivation.


    Based on what I've seen here over the years it takes 3 to 10 (or more) years for the average WBF'er to complete a build. Are you willing to spend that much time (and pounds/euros) working on an unproven design?
    It's not unproven. And I spend at least 1500 hours a year working on my house, my furniture projects, and other workshop-related activities, in addition to my job. I've done that and more for the last 7 years, but jobs are going to run out in about 9 or 12 months. I've seen build times given for these sorts of boats of between 900 and 1200 hours, so I reckon a year should be enough. If it isn't, it won't be far off. The money? Well, that's my choice, and I'm lucky enough to be able to afford it. And if after I've built it I then find sailing isn't really for me, I'll sell it. The point of this exercise is the process, not the result.......the same with much of what I do, I reckon.

    Quote Originally Posted by stromborg View Post
    ......I still think Mike ought to get some time on the water.......
    You are right about that, though.
    Last edited by Mike-in-Suffolk; 09-09-2021 at 12:52 PM.

  14. #49
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    Default Re: Whisstock design #146: potential keel variations

    As a serial builder, I get feeling like you're running low on projects. It slipped past me that you had focused in on the #146 and that you have George onboard. Looking forward to seeing you start.
    Steve

    If you would have a good boat, be a good guy when you build her - honest, careful, patient, strong.
    H.A. Calahan

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by stromborg View Post
    .........Looking forward to seeing you start.
    So am I. Now, could you just help persuade my wife.......

  16. #51
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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Mike-in-Suffolk View Post
    That's really interesting, The Q, and thanks for it. All part of my education.

    However, I am very much at the other end of the experience graph from you. Getting a tack timed right to get me within 5 or 6 feet of a bank I would probably count as something of a triumph! A centreboard 300mm off centre wouldn't make any noticeable difference to me for a while at least because I have nothing to compare it with. Most of my sailing was decades ago in Hoby Cats, available for hire on most popular Australian beaches in the 1970s and 80s. Turning on a sixpence with one of those generally resulted in face-planting into the sail as you both hurtled towards the surf.....again. I don't expect to be testing any new boats limits, at least for a good long time.

    Have you seen the drawings of the 146? Here is the longitudinal section. It has a long but shallow central keel with a chunk of that made up of a lead ballast keel. I'd be interested in your thoughts, in light of your comments about long keels and river sailing. I don't expect to do more than a week a year in the Broads, so that my wife, who gets sea sick in the bath, can have a ride on a boat without too much discomfort. Being perfect for the Broads isn't critical, therefore, as most of my sailing will be in the estuaries of Suffolk and Essex. Heaven forfend, I might even get over to north Kent one day if feeling really brave. I can imagine, therefore, that much as I'd like to sail everywhere, if we did have an upwind river journey to do which involved endless tacking that the outboard-in-a-well would cease to be just ballast.
    I may have more experience of sailing on the broads, but your boat will be beautifully built, I'm just good at hiding cockups with paint..

    Having had a peer at the 146, that looks like about 4 inches of external dead wood, plus the larger section aft, I think compared to a Broads sailing boat she will be a slow tacker, But not enough to stop you sailing the wider rivers, The Narrower rivers like the Ant, the Thurne above Potter Heigham, The Bure above Hoveton /Wroxham Bridge will require an Iron topsail, to someone inexperienced in the broads people often do for those sections anyway.. However they are worth visiting with Barton Broad and Hickling Broad being eminently suitable for you to go for a sail and pretty.

    Here's a video of The Rivers Ant and Bure from a Wayfarer dinghy, just after 5 minutes 45 seconds in you see some sailing Cruisers at my sailing club at Horning circling for their start. They being designed for it can and do sail up the River Ant . https://youtu.be/WWz-XxEiry4

    And just to frighten you, if you visited the first weekend in June most years you'd see this.. The 3 Rivers race at Ludham Bridge on the River Ant with some of those big Broads cruisers amongst others including myself in there somewhere in a Yeoman https://youtu.be/WOpGhAqFBqg

    (note next year the 3RR is early, being the weekend before the bank Holiday, which will be a week late)
    Last edited by The Q; 09-10-2021 at 01:51 AM.
    Just an amateur bodging away..

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    Default Re: Whisstock design #146: potential keel variations

    Frightening! And that boat that went nose-first into the bank...... Looks a whole lot of fun if you've got a clue what you're doing. I might make a plan next year to go up and watch.

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    Default Re: Whisstock design #146: potential keel variations

    I think the 3 Rivers Race is the 23rd / 24th May next year, early because of the Queens anniversary, This has to be confirmed, as all the sailing Clubs on the broads coordinate their events so as not to clash and they haven't had that meeting yet.

    Because you can choose to sail round the course in any order and the course is tidal, there are variations in where the majority of boats will go first.. A quick look at the tide tables indicates high tide is around 12:00, just short of spring tides, the starts are normally between 11:00 and 12:30.
    So I think, if there is a reasonable wind, most boats will choose to go to Ludham bridge first, so peak time there between 12:00 and 14:00.
    The other main viewing points are Potter Heighham bridge and Acle Bridge, the fastest boats will go to Potter Bridge first arriving at say 14:00, the rest will go to Acle bridge after the Ludham and south Walsham legs starting to arrive arriving at maybe 16:00..

    This is of course a guesstimate way ahead... Once things are confirmed I'll Start a thread for the 61st 3 Rivers Race 2022, with race times, best places to view / park, anything else relevant and then update it as further information comes in..
    Just an amateur bodging away..

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    Default Re: Whisstock design #146: potential keel variations

    Having had a peer at the 146, that looks like about 4 inches of external dead wood, plus the larger section aft, I think compared to a Broads sailing boat she will be a slow tacker, But not enough to stop you sailing the wider rivers
    Yes – the depth of the keel outside of the hull skin is about 80mm at the forefoot. The profile is faired in from 60mm to 25mm full width on the leading edge.

    It's always a bit of a compromise – on the one hand you want a straight running boat under most sailing conditions – on the other you want to be able to spin on a sixpence in crowded anchorages, or confined waters like the broads!

    #146 will tend to pivot on the deeper keel aft, but you will still be wanting a bit of boat speed to tack very quickly. If you look at the Design Data, https://www.whisstock.com/page_02.ph...6#open_modal10 for the boat you will see that she is lightweight for her waterline length, and both Sail Area/Wetted Surface and Sail Area/Volume of Displacement ratios are at the high end of the average range – indicating good light-weather performance, which should be helpful in waters like the Broads as she will accelerate quickly. The mizzen will also help push her round quickly on a tack.

    For heavier weather sailing and more exposed coastal sailing one might well douse the mizzen and roll away the jib – under main and staysail she should be pretty snug. There is also the option to add 100kg of internal ballast for that type of cruising.

    Another modification that is worth considering is to set the staysail on a club boom so that it is self-tacking. Then under combinations of main, mizzen and staysail you can turn up a river or through an anchorage without having to tend sheets at all. No good for a Broads race perhaps, but really quite nice and relaxing for a calm evening sail ....

    Cheers -- George
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    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    A club boom for the jib or stay sail is a good idea, I've incorporated one in the design of Blue Moon, being a single hander tacking in our narrow rivers, I just didn't want the hassle of tacking the jib at the same time as helming and controlling the main..(and watching the opposition)
    As you say Light weather performance on the broads is important, the average windspeed is 12mph and if you take away the winter gales that brings it down more.. Then between trees and houses even less..
    Just an amateur bodging away..

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by debenriver View Post
    ......The mizzen will also help push her round quickly on a tack....
    George, have you done a sail plan without a mizzen? And/ or with a single headsail?

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Mike-in-Suffolk View Post
    George, have you done a sail plan without a mizzen? And/ or with a single headsail?
    Not for #146 currently, though it's no problem to do. #077, #119 & #123 all have cutter rig plans and have been built with both cutter rigs and yawl rigs. #165 has cutter rig, yawl rig and sloop rig.

    I think for ease of sailing under a variety of conditions, I would keep the mizzen and convert the staysail to a club boom – it reduces the area a little but self-tacking is a big advantage. If you want to keep things simple, personally I would not go for a sloop rig as the larger single headsail will be more of a handful, even with reef furling – and when reefed on the furler, the centre of effort will tend to go higher.

    Under main and staysail you have quite a snug rig, that is equivalent to taking in a first reef. Under mizzen and staysail you have a very snug and controllable rig indeed – without all the hassle of reefing the main.

    But whatever - I'm happy to include a cutter rig sail plan in the plans package ....

    Cheers -- George
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    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    That's great George, thanks. Insitinctively, and only from an aesthetic/ emotional point of view, I'd plump for a sloop. But I guess I'm persuadable on a cutter. I really don't want a mizzen.

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    Default Re: Whisstock design #146: potential keel variations

    Now I've had time to look at the figures over lunch, she, 146 is of lighter / faster performance than the style of boat looks..
    Nothing like Blue Moon, but the boats are for different purposes. Blue moon has a chair to sit it... No outboard to carry, no berths etc..

    Blue Moon, LWL 4.88M, BWL 0.91M, SA 12sqM, Hull body draft 150mm, Sailing Displacement 500kg, of which 150kg is lead at the bottom of a 0.91M fin, and 100kg of movable ballast... me
    Just an amateur bodging away..

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    Default Re: Whisstock design #146: potential keel variations

    George, I assume that is a post under the tabernacle, is it, between the two sides of the forward berths? Would it be possible or practical to do away with that and bump up the frames/ bracing, locally?

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    Default Re: Whisstock design #146: potential keel variations

    Yes - I've done that on both #165 and #119 (see image). #146 would be similar.

    119_frame.jpg
    Cheers -- George
    To be truly free to live, one must be free to think and speak.

    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    Thanks George. That may be a small step towards convincing my wife that this is a sensible idea!

    It looks like that decision could be made quite late in the day if you leave the vertical element of the ring frame (the coach-house side supports) long initially.

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Mike-in-Suffolk View Post
    Thanks George. That may be a small step towards convincing my wife that this is a sensible idea!

    It looks like that decision could be made quite late in the day if you leave the vertical element of the ring frame (the coach-house side supports) long initially.
    Yes that's true – but really you might just as well make it from the get-go. It's not so very difficult and you have the freedom to make the vee-berths into a double if you wish to.

    Here's the mast frame (plus the two forward of it) on a modified #119 – beamier and 10% longer. The same frame on #146 would be very similar.

    slideImg17.jpg

    Cheers -- George
    To be truly free to live, one must be free to think and speak.

    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    Paul, I am wondering about the possibility of building the #146 using traditional clinker rather than glued ply clinker. I have just come back from Sweden, and I happened to see a Folkboat in beautiful nick, and bright finished above the waterline. It looked great, and, importantly, my sceptical wife really liked the look of it too. I've never really liked bright-finished ply. Would there be any great problem building this with western red cedar boards and copper rivets & roves? Or is the strength of this boat down to a monocoque construction relying on the epoxy on and between the strakes?

    Importantly, my wife has come around to my way of thinking, and understands that not only do I need to build a boat, but that we need a boat in our lives. It's only taken me about 6 months.......

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    Default Re: Whisstock design #146: potential keel variations

    Best ask George about this..
    My thought is, trad clinker needs to spend most of the time in the water, which is not what trailer sailing is about?
    I have John Leather's book on Clinker Boatbuilding, you are welcome to it if you send an address.

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    Default Re: Whisstock design #146: potential keel variations

    As designed the boat relies on an epoxy bonded monocoque structure. The epoxy bonded plank laps are essentially longitudinal stringers and the hull skin panel areas are quite small (essentially frame-to-frame and lap-to-lap rectangles). Also the epoxy bonded hull, deck and superstructure is structurally stiff; and elements of the interior furniture are epoxy bonded in to add stiffness to the hull. It all goes to make an elegant, lightweight and efficient structure.

    The importance of the epoxy coating is more about keeping the elements of structure at their strongest (because they stay at less than 12% moisture content), than any real effect of the epoxy skin itself. Because we can rely on a pretty constant moisture content, we can engineer the structures for a reasonably consistent strength rather than having to rely on the timber at its weakest and wettest.

    Traditional clinker doesn't do this so well because it's relying on fastenings and friction, hence there would need to be steam-bent timbers at about 150mm centres between the main laminated frames. And even so, the structure wouldn't be as rigid as the all epoxy bonded structure is. And making the secondary structures (like cockpit sides, bunk fronts etc.) serve a secondary structural purpose is much more difficult. Further, it's not easy to effectively epoxy coat a clinker hull (not impossible of course), so the timber components are going to get wetter and drier and shrink and swell and the engineering of the structures has to be based around timber in it's weakest condition rather than its strongest.

    If you did go that route, I wouldn't recommend WRC as hull planking clean European larch, Douglas Fir (not particularly durable however) or one of the Mahogany substitutes would be much better. The boat would be heavier of course, even though clinker provides quite a lightweight construction, and structurally more flexible.

    Traditional clinker is not so suitable for trailer sailing depending somewhat on the afloat/ashore balance. If you spend long periods ashore, you could find that most of your sailing is spent taking up! And one of the nice things about a wood/epoxy sailboat is that more of the effort of the sail plan can go into driving the boat forward because the structure flexes very little, rather than being absorbed by structural movement and flexing.

    I sail a traditional (carvel) boat and I really like traditional carvel and clinker boats and my background is building them but they really need to be kept afloat for the season and you really need to know about maintaining them, accepting leakage and water in the bilge (so sometimes damp lockers and damp things stored in them!) and so on.


    So - to sum up while it's perfectly feasible to modify the design for traditional clinker, it might not be the best thing to do considering how you will be using the boat.

    Cheers -- George
    Last edited by debenriver; 09-27-2021 at 07:45 PM.
    To be truly free to live, one must be free to think and speak.

    A C Grayling

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    Default Re: Whisstock design #146: potential keel variations

    Thanks George for another really useful response. I rather thought that was what you might say. I shall revert to Plan A. The only thing I am not looking forward to in this project is all the epoxy-ing. I'm a woodworker......

    Interestingly, (well to me, anyway), Mark Reuten of Nomad Boatbuilding Youtube channel, bonds the laps of his clinker boats. This should reduce the taking up issues with boats kept out of the water.

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    Default Re: Whisstock design #146: potential keel variations

    There is a big difference between the the lap construction use of epoxy as a glue and the stitch and fillet method, used by say, Devlin. I bought a set of plans for his Winter Wren, but decided against it because of the method.
    As a woodworker, the close fitting joints in ply lap and the rest of the boat, are a long way from googing joints with large amounts of epoxy and tape. (it does allow for a bit of error though )

  34. #69
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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Andrew2 View Post
    There is a big difference between the the lap construction use of epoxy as a glue and the stitch and fillet method, used by say, Devlin......
    Indeed. Mark Reuten, though, does a hybrid, using traditional rivets and roves, but with a bead of a flexible sealant set into a shallow groove on (both faces of?) the lap.

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    Default Re: Whisstock design #146: potential keel variations

    Quote Originally Posted by Mike-in-Suffolk View Post
    Indeed. Mark Reuten, though, does a hybrid, using traditional rivets and roves, but with a bead of a flexible sealant set into a shallow groove on (both faces of?) the lap.
    Doubt that it increases the rigidity of the hull much, likely does solve the seepage during taking up problem. Think I will stick with glue....

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