fiberglass canoe conversion to expedition sailboat

Discussion in 'Sailboats' started by josh907vest, Feb 22, 2016.

  1. josh907vest
    Joined: Feb 2016
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    josh907vest Junior Member

    i do plan on getting a dry suit, my mom would kill me if the cold water doesnt.. haha. and ive been watching some videos on the out riggers, i might just have to get some for ocean sailing, better safe than sorry.
     
  2. latestarter
    Joined: Jul 2010
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    latestarter Senior Member

    It has been found that it is better to have a single slightly longer board than the extra weight of 2 shorter boards. The main advantage is you can tack without having to raise and lower boards.
    This is a tried and tested method.
     
  3. Tiny Turnip
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    Tiny Turnip Senior Member

    In addition to the highly recommended security, outriggers will limit the heel, and the amount the leeboard rises when on the starboard tack.

    The long leeboard foils can be very high performance, and generate a lot of moment at the pivot point. It does need to be very strong. Mine was attached to the thwart with an 8mm thick aluminium angle bracket, and it still managed to exert enough force on the hull to pop a blister of ply out.

    It is also common to use very long (5 or 6 feet) tillers; the grip off a golf club makes an excellent handle.

    If you went Bermudan on both masts then unstayed masts will allow you to reef by swivelling the mast a couple of times to haul in some sail.
     
  4. josh907vest
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    josh907vest Junior Member

    Heres another sketch, again.. This is just a quick drawing, nothing to detailed or scaled. just getting my ideas on paper. But on this one, i have a higher deck so i can sleep in the front part of the boat, and have plenty of storage in the back part. Also, outriggers that would pretty much make this boat a trimaran. a single leeboard on the port side, and a forward mounted tiller with wheels and rope controling the rudder. So yeah, what do you think?
     

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  5. Steve Clark
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    Steve Clark Charged Particle

    The problem with open sailing canoes isn't tipping over.
    It is sinking. They can go fast enough to drive themselves under or fill from spay and waves comi8ng aboard.
    Paddling canoe topsides are arranged around paddling, which means that they have are low and have tumble home to keep your lower hand closer to centerline and the water. This is counter to the needs of keeping waves out of the boat. So keep the cockpit as small as you can and make sure you have watertight bulkheads and hatches. Good pumps and balers are also important.
    Experience has shown that a single lee board is better than two lee boards. If you are going trimaran, the boat isn't going to heel much, and even if it did, the canoe hull is so narrow that the lee board doesn't "come out of the water" much if at all. Having only one is half as heavy, half as expensive and twice as fast to build.
    Lee boards, even when not in use, catch waves and throw water around and I would much rather have a centerboard or dagger board. The trunk can be arranged as a perfectly nice place to sit in the middle of the canoe, either for rowing or paddling with a double blade. Installing trunks in wood canvas canoes was problematic. On a fiberglass canoe it is pretty bog simple.
    C Class Canoe Chamberlin.jpg
    A canoe I built years ago for the ACA "C" class, the underwater shape is identical to a fast tripper, topsides are flared outboard, the gunwales are 4" wide and the fore deck is turtled to keep the water out. It came back to me after 20 years and I have modified it beyond the class rules. Now has even wider gunwales ( to make rowing better, and a dagger board trunk to put the rowing seat on. I use a Byte CII rig.
    View attachment Chamberlin at start of 201r rally.doc
    Seen here next to some identifiable other boats for comparison.
    Rows well, sails nicely, looks sharp, I jind of like it.
    SHC
     
  6. sharpii2
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    sharpii2 Senior Member

    Josh.

    For what you want to do, you are going to have to divide the canoe into three compartments, with you sleeping, paddling, and sailing in the middle one. The other two, being about 4.5 ft long, will have enough buoyancy to keep the boat afloat even if the longer center one is flooded.

    The cross beams can then attach to the ends of these compartments, so they will be about 7 ft apart. Since they will have some depth to them, they may well double as crude splash boards. They can be closer together, if you are willing to deck over some of the center section. I'd only deck over just one end of this section. This is where I'd tuck my feet, while sleeping aboard. My head, shoulders and butt would not be hemmed in by any deck this way, so the deck height can be within reason.

    The floats could by made out of styrofoam, covered with painted canvass. If you go to www.Duckworksmagazine.com you can read some articles on how this has been done to make kayaks and SUP's. Making them this way would confer two advantages:

    1.) they would be quite light, cheep, and easy to shape, and
    2.) they will provide a lot of emergency flotation, should you get swamped.

    I'd make them at least 10 ft long and try to keep their over all volume to less then 2 cubic ft each. This way they will never have the volume to lever the main hull out of the water, making the boat even harder to capsize.

    I liked your original rig because the sails where of different sizes. This is useful in a tiny boat, as a third mast step can be arranged, and one mast and sail can be stepped in it while the other mast and sail are stowed.

    This is a very handy way to reef and was used in many two masted work boats during the age of sail. This gives you a choice between three different sail areas, without you having to tie a single reef. It also eliminates the drag of bare mast above the sails.

    The Boomed Lateen you drew would be handy for three reasons:

    1.) a good portion of the Boom ends up in front of the mast, so it's Mast can be stepped a little further aft from the Bow,

    2.) The weight of its long yard will bring it down quickly, once the Halyard is released. This would be useful in a sudden squall, and

    3.) its triangular shape will make it a better upwind sail than a Balanced Lug, as the Yard Is tied to the Boom.

    Striking the mizzen quickly is not as big of an issue is being able to strike the main, as the struck main will reduce the SA by a little less than 2/3rds.

    The still standing Mizzen can help weather cock the boat up wind, so it can handle waves head on.

    I calculate that, with a 10 ft yard, a 10 ft Boom, and a 1:1 pitch for the yard, the Main will have about 35 sf, with no roach at all. The Mizzen, with a 5 ft Boom and a 9 ft hoist would produce another 22 sf, with no roach at all. This would produce spars that are all shorter than the boat, and could be lashed to the cross beams when not in use. This would be the case on a windless day, when you have to paddle for miles.

    I disagree with the idea of putting a centerboard trunk in the Hull. Such will likely spoil the open space in the center section, or it will have to be offset so much to one side that the case would be very difficult to join with the curves of the hull. Also there is the problem of an unexpected grounding at speed. This could easily tear a hole in your Hull which would be difficult if not impossible to repair, in the field.

    A single Lee Board, which is shifted from side to side, is much simple, far less likely to damage the Hull, if it strikes the bottom at speed, and can be easily stowed aboard when not needed, as when sailing down wind. Also, it leaves no draggy slot, when pulled out of the water. This is particularly true when paddling through a calm.

    Since the floats are likely to be quite narrow and blade like, you may be able to dispense with leeway preventors all together. The floats themselves can act as long keels. They can also be arranged so they both clear the water when the canoe is being paddled.

    Attached is a sketch of a system I designed for a strap on rig for a kayak. Here, the floats have long keels under them, but the keels only immerse slightly, while the boat is upright.
     

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  7. AnthonyW
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    AnthonyW Senior Member

    Solway-dory

    Solway-Dory in the UK sell expedition canoes, and they are a few videos on the web of their canoes, and I recall a nice blog of some quite nice long expeditions done in their canoes. They have a nice website. Both their Shearwater and Fulmar canoes have small outriggers, though they also sell a lovely looking trimaran canoe called the Osprey. It looks like what you have planned is a 'one off' halfway between one of their canoes will little outriggers for stability, and their Osprey.

    The Osprey has two masts, as recommend (if I recall) by an earlier poster. Might be more stable.

    It looks like you are not going to compete with them, just build a one-off rig, so I am sure they may not take offense if you approach them with some questions, provided it did not ask any overly proprietary information.
     
  8. AnthonyW
    Joined: Oct 2012
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    AnthonyW Senior Member

    Forum for sailing canoes

    http://www.songofthepaddle.co.uk/forum/forumdisplay.php?135-Canoe-Sailing-and-Sailing-Canoes

    Might have some interesting information.

    PS - Second Sharpii2's comments above on rig, leeboard, and 'floats'. Centreboard would be a right pain to make the case, and in the way. Not easily undone either. I would start with a leeboard and if whatever reason you really want a centreboard, then find a more suitable canoe and start again. I think the canoe with a rig could be a great deal of fun, but building a centreboard case long enough for it to kick up would kill the space, and seems to me like putting low profile tyres on a panel van.
     
  9. Steve Clark
    Joined: Jul 2004
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    Steve Clark Charged Particle

    The centerboard on a small sailing canoe doesn't have to be very big. Something like 24" by 6" is big enough if it is shaped properly. A lee board has to be probably 50% bigger.
    The lee board thwart isn't invisible and takes up a lot of space as well, just in a different axis.
    Centerboard cases are boxes taped to the inside of the hull with resin and glass.
    If you can install watertight bulkheads and put a deck on something, you can build a centerboard case. If you can't do that, you should not trust the rest of your carpentry, and you shouldn't go to sea in anything you built.
    Next point: You are going to have some sort of "board" to stop the boat from sliding sideways under sail. You are going to have to carry it around with you whether you are using it or not. You can hang it on the side of the boat, where it will be in the way, will splash in the water, and generally be a pain in the ***, and be in the way almost every time you try to do something.
    Or you can build a housing for it where it can live and be stored and used. Yes it will be in the way, but you have already decided to add a pretty big pile of stuff to a simple canoe hull. I prefer to do things as efficiently as possible because it results in the best compromise. A little space in the inside of the canoe in exchange for better sailing performance, easier handling under paddle, and fewer things to get hung up on and bump into. The lee board is always in the way, and the only thing worse than one of them is two of them!)
    It gets even worse if you want to use a long double blade paddle. (which is what the Hudson River guys all did.) In order for sailing canoes to deliver the goods, they have to be clean and efficient. Once you give that up, there is little point in them and you should start your quest someplace else.
    SHC
     
  10. gggGuest
    Joined: Feb 2005
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    gggGuest ...

    And honestly people, its hard to think of a constructional job much simpler than removing a redundant centreboard case on a fibreglass craft and filling up the hole where the slot was.

    I was very struck recently by a commercial sailing canoe that turned up where I sail and which was nothing but complication and irritation in the rigging, with the leeboards a significant part of that. A little centreboard case with the board permanently stowed makes for simplicity. Its also a great deal easier to make it strong, and it will be almost certainly be lighter too, what with the smaller size of board and simpler engineering for the case.
     
  11. sharpii2
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    sharpii2 Senior Member

    In my last post, I should have said "Dagger Board" in place of "Center Board".

    A Centerboard would be my second choice, if for some reason a Lee Board could not work out. This happens a lot, as the Center of Area (CA) of the sails doesn't always correspond to the widest part of the Hull, which is the only suitable place to put the Lee Board(s).

    A Center Board trunk could be put anywhere along the Length of the Hull, even in the very Bow.

    I see no reason a Lee Board would have to have 50% more area than a Center Board.

    The Center Board will have to project into the hull, when it is lowered, just as the top portion of the Lee Board will have to extend above the WL, though the extension ave the WL will probably be greater with the Lee Board.

    There are many ways to mount a Lee Board and only one way to mount a Center Board. The Center Board needs at least one rigid wall to pivot along, which, with the exception of a straight, vertical sided scow, means added structure. A Lee Board can be made to work with very minimal alteration of an existing hull, and it, like a Center Board can be made short and deep. When not in use, it can be stored on top of a deck.

    Although it is true a pair of Lee Boards makes changing tacks more convenient, one can be used, if it is shifted to the lee side with every change in tacks.

    Adding a bulkhead to a canoe is probably a lot simpler than adding a Center Board trunk, especially if one wishes to move it off to one side, so it doesn't interfere with the main working (and sleeping) area of the boat. This is especially true if the Canoe has a lot compound curves along its side.

    If the canoe has a relatively flat bottom, with a rounded bilge, the trunk can be installed in the flat portion of the bottom, just before the rounded bilge starts. The trunk has to be designed carefully, though, as it creates a hard spot at each end. I've see a number of old FRP boats with cracks on either end of the Center Board trunk. These were probably not caused by the loads of the Center Board itself, but by the flexing of the hull areas, just in front of or behind it.

    Bulkheads may save a boat from sinking, even if they are not 100% water tight. If they leak slow enough, the boat can be bailed out long before it sinks.

    But the Center Board trunk had better be absolutely water tight or it will be a source of insipid leaks.

    As for convenience of use, my vote goes with the Center Board over the Lee Board. But when it comes to simplicity of engineering, my vote goes with the Lee Board.

    My next boat will have one.

    Attached is a top and side view of one I have designed.

    It hooks onto the lee side deck, though it has a bow line that doubles as a lanyard, to keep it from being lost overboard.
     

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  12. Steve Clark
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    Steve Clark Charged Particle

    C Class Canoe Kattell.jpg
    From former open canoe champion Ed Katell.
    This is what testing (as in racing against other canoes with the same sail area) proved worked best. All these boats have single lee boards and do not shifty them from side to side.
    Once again tested and found superior.
    So if you want to use a lee board, the guys who have made open canoes with lee boards sail the best, only use one.
    Ed calls for 48-56" x 10" lee board.
    Of course about 6" of that sticks above the gunwale as part of the lee board bracket which is a piece of 4" aluminum angle sitting on top of a 3/4" piece of Oak or similar hardwood. The thwart has to be stiff enough to withstand the prying effect of the lee board when it is on the windward side. Then the lee board is to leeward, it will bump into the hull before it bends too much.
    So the wet part is probably in the order of 36" x10" or about 2.4 ft^2 if you use the short numbers.

    My current dagger board is 6" wide and 42" long. 6" is inside the boat, so the exposed area is 1.5 ft^2. It is a NACA 63010 section and seems fine. It may even be too big.

    SHC
     
  13. sharpii2
    Joined: May 2004
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    sharpii2 Senior Member

    Thank you for the drawings, Steve.

    What works best for racing is often not what's best for cruising.

    Racing under sail almost always disproportionately rewards windward ability. This is because, if the race course is divided into three equal length legs, with one being directly up wind, the upwind leg will account for at least 47% of the actual sailing, probably more, as the boat usually sails slower when sailing upwind. The more weatherly a boat is, the smaller this percentage becomes.

    I would never want a sailing canoe with a board that deep. This is for two reasons:

    1.) the actual sailing draft ends up too deep for the littoral use a cruising sailing canoe is likely to see, and
    2.) the structural loads and the heeling force both increase with a deeper board. None of these are good for casual sailing, where they probably need to be tolerated for effective racing.

    Much if not most cruising will be across the wind, not into it. Upwind ability is certainly a must, but doesn't necessarily need to be the top priority. So, if you have a boat that sails 50 Degrees off the wind, instead of one that sails only 40, but is rugged, has reasonable sailing draft, and lower concentrated loads, it might be the better deal for cruising, even though the one that sails 40 degrees off the wind will be about 20% faster up wind.

    Is funny to think about it. I came up with my Lee Board idea going in the opposite direction your friend went.

    I started off with two side Center Boards, which were to be both down at the same time. I found that this would take me past my material limits of three sheets of plywood for the whole boat, with the Rudder and Board to come out of that.

    I next went with a single side Center Board, which reduced the amount of material. Bu,when I looked at it, I said **** This Board has to be awfully deep on one tack to be adequately deep on the other. This extra depth increased the bending loads on this Board significantly.

    I then asked myself how hard would it be to have to shift the board over to the other side when ever I changed tacks.

    I decided it wouldn't be all that hard at all, especially if I could get the boat to sail across the wind without the Board being deployed. But I certainly wouldn't want to have to do this while racing.
     
  14. bpw
    Joined: May 2012
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    bpw Senior Member

    Don't overthink this, bodge together whatever is easiest and go have some fun. It won't sail great no matter what, but that's OK, it will still take you places.
     

  15. gggGuest
    Joined: Feb 2005
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    gggGuest ...

    I was mulling over this business of foils for canoes, and came up with a probably crazy idea. This is based on the setup our great great grandfathers had on the early canoes.

    Now obviously this isn't a racing setup, because the aspect ratio is pathetic, but here's some of the thinking.

    Firstly the drag isn't as bad as it might be because a centreboard is intrinsically way superior to a leeboard because its not surface piercing.

    The board is shaped so the section where it comes through the hull is a constant hydrodynamic section, so there is no open slot, no gaskets to worry about and minimal interference, drag reduced again.

    The pivot is above the waterline, so avoids the problems with sealing a bolt, and the only other hole in the case is for a line to raise the board.

    Because the trailing edge never exits the case the line to raise is never in the waterflow and can be to the tip so minimum effort to raise the board.

    Because it is raised with a line there's no need for a handle to impinge on the boat - the top of the case is solid all the way.

    The hydrodynamic section means the board is more efficient than a flat plate.

    The section for the angled leading edge, however, must be heavily compromised to keep the section through the slot constant, but on the other hand if it is bumped through the shallows a bit more meat there will do no harm.

    Shallow angle of the plate will normally bump up, although the upper section will catch ropes and weeds. However it should lift up to clear very easily.

    Two strong points are required, but the pivot and front of the case are assumed to be the mast post, so its just a question of arranging a bit of lateral support for the raised section which is there to deal with the loads. This can probably be triangulated back from the mast bulkhead, so less intrusive than cross beam arrangements for leeboards. The end plate effect means its roughly as efficient as a leeboard of twice the depth, so the leverage from lateral loads is roughly half.

    CLR doesn't vary nearly as much as with a modern board that projects completely below the boat.
     

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