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cam or clam cleats

Discussion in 'Canoe Sailing' started by chris pearson, Jul 4, 2011.

  1. chris pearson

    chris pearson Michigan Canoe Nut

    Hi guys. I'm a novice sailor and heres something I want to improve upon. Where specifically do I put a clam or cam cleat on my leeboard thwart? What angle? Obviously I need to be able to switch the mainsheet rope as I switch sides when tacking or adjusting for wind variation. Photos will really help detailing this. I'm sure I''ll learn allot at the assembly too. Your hand gets pretty tired unless you wrap it around something first like the lock down handles for the thwart clamps.
    Next question, my sail rig was new old stock right out of the box. The boom is parallel to the gunwales. Shouldn't it be slightly raised at the aft end? Could the factory placement of the gooseneck be too far back? Apologies in advance to Todd, just in case he talked about this in his wonderful book and I missed it!!!!!
     
  2. OP
    OP
    chris pearson

    chris pearson Michigan Canoe Nut

    Also, do you face the leeboard brackets up or down?
     
  3. Todd Bradshaw

    Todd Bradshaw Sailmaker

    How you cleat it depends on how you route your mainsheet, and there are lots of possibilities. Cleats (either cams or clams) have fairly narrow working angles, so you usually need something down at deck level (a block or fairlead) to take the mainsheet as it comes down from the boom and route it to the cleats.

    My favorite system is to deaden (secure) the mainsheet aft (to the aft deck, gunwales, a rope traveler, etc.) then run it up to a block fairly far aft on the boom, then along under the boom to a second boom block just behind the mast. From there, the sheet leads down to deck level, through a block attached to the lower mast or mast thwart and aft to the sailor. An open clam cleat (has no built-in fairlead) on either side of the leeboard thwart can be used to cleat it. See drawing below.

    The major advantage to this system in that the forward boom block forms a very effective automatic downhaul, flattening the sail when mainsheet tension is high and easing it for more draft as sheet tension decreases. It will work well on just about any sail that has a gooseneck or boom jaws that are free to slide up and down the mast. Either cams or clams can be used, but if you buy camcleats, make sure they are ball-bearing models (Harken, Ronstan, etc.). The non-ball-bearing cams have a tendency to jam at precicely the wrong time and you can't get the damned sheet free to ease the sail out and save your bacon. In general, Clamcleats are just as effective for this use and easier to deal with.

    Yes, the aft end of the boom is usually higher, but on old Old Towns, often not by a lot. The higher tail end allows the boom (and the sail's clew corner) to have a bit more clearance above the water as the boat heels and the sail is let out to the side. One of the most common capsize scenarios for lateen sails happens when a big puff of wind hits and the sailor eases the sail out to de-power. If the boat is heeling and the sail's clew corner hits the water, the corner will plane along on the surface, preventing any further easing. At that point, if the wind pressure is greater than the sailor's leverage as he hikes out (or doesn't) then the boat rolls over. A little upward angle aft on the boom helps to build in some safety margin to prevent this (so do really tight abs and the ability to hold the boat flat through a puff).

    It's been so long since I saw one of the stock brackets that I don't remember how it was oriented. Somebody will know.
     

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  4. Dan Miller

    Dan Miller cranky canoeist Staff Member

    Several Old Town catalogs show them with the brackets facing up. With the brackets facing down, it will be more difficult to reach the lever bolt as you raise and lower your boards.
     
  5. Benson Gray

    Benson Gray Canoe History Enthusiast Staff Member

    I usually mount the leeboard brackets face up to help keep the canoe dry. A close examination of the picture at http://forums.wcha.org/attachment.php?attachmentid=10026&d=1268689103 shows a small wave that rises vertically up the leeboards as you start to go faster. Having the brackets up increases the speed you can reach before you start getting wet from spray. I think that they look better mounted down but I will only rig them this way if I don't expect to be going fast.

    I prefer to keep the sheet in my hand and will use a pulley on the boom for a mechanical advantage that eases the strain. This is also shown in the picture mentioned previously. I have a sailing canoe that has old cleats for the sheet on each inside rail as shown at http://forums.wcha.org/attachment.php?attachmentid=6486&d=1226688183 and http://forums.wcha.org/attachment.php?attachmentid=6489&d=1226688183 but I don't use them.

    The easiest way to change the boom angle is to move the point where the halyard attaches to the spar. I usually keep the aft end of the boom raised slightly. The table at http://forums.wcha.org/attachment.php?attachmentid=1064&d=1136757320 lists the original locations of the Old Town gooseneck / jaw and the halyard attachment point for various sail sizes. The message at http://forums.wcha.org/showthread.php?969 has additional original Old Town sail rigging information if you are curious. Happy sailing,

    Benson
     
    Last edited: Jul 4, 2011
  6. OP
    OP
    chris pearson

    chris pearson Michigan Canoe Nut

    Wow, thanks for the info guys.........
     
  7. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Just remember that if you turn the bracket over, you also have to turn the leeboards over to avoid the dreaded "airfoil effect" :)
     

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  8. OP
    OP
    chris pearson

    chris pearson Michigan Canoe Nut

    He, he, he........
     

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