Aftmast rigs???

Discussion in 'Sailboats' started by jdardozzi, May 28, 2002.

  1. Barra
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    Barra Junior Member

    Now that brings back memories. Having cut my teeth (so to speak) on catamarans with centreline centreboards , i'm not sure they were dumped because of " end -plate issues". Just my opinion , mind you.:p

    The Arafura Cadet and Arrow were probably the last designs with them?

    The Quick Cat was a beast.

    There was a lot of structure and weight tied up in the large center board.IMO

    There was also a lot of pain and blood-shed involved in negotiating a route around the structure during tacks.

    I'm sure one could prove with math that no endplate is detrimental, but there was the advantage of moving the CLR aft with a small swing of the boards and the kick up when grounding. Maybe boat design became less practically orientated.

    Basically soft decks and the quest for lighter boats were the death knell of centreline centreboards on cats. IMO:D
     
  2. DennisRB
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    DennisRB Senior Member

    I'm sure in this thread a startup designer posted about his 35ish aftmast (with main sail) cat with some nice renderings. He was also using a center "spine" hull of sorts with a kick up centerboard. I think its a great idea. No slot drag with the "spine" hull out of the water, but the board can still kick up and you can move the CLR back. Yeah we will all agree there must be more drag due to the surface peircing nature of it, but also remember one large foil has less tip drag than 2 small ones. I think performance will be good and the other benefits are well worth it. Also if the design has this spline anyway it could actually weigh less without the wasted board length and dagger cases?
     
  3. brian eiland
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    brian eiland Senior Member

    Don't recall any of these?

    I was a significant dealer/distributor for Stiletto cats, and that was my primary exposure. Yes they did have 'end plate' issues at the water's surface, and they did have a rather unsophisticated support structure.

    I'm assuming the center board you are referencing was brought all the way up thru the central deck?....that's what made it so large and heavy?

    I'm again assuming that was a deck side issue with that centerboard?
     
  4. brian eiland
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    brian eiland Senior Member

    Don't recall that 35ish vessel you noted?

    The subject thread where I first proposed this idea was never responded to,...that was way back in 2003. I'll repeat it here and underline a few of the positive attributes I forsee.

    Back a few years ago I took some of these same ideas and incorporated them into my Dynarig cat idea
     

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  5. Barra
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    Barra Junior Member

    I was merely reminiscing out loud . this was not meant to end up as another boat-design captain keyboard pissing competition.

    Google is your friend re boat specifics.

    All boats mentioned predate your Stiletto thingy.

    Cunninghams Quick Cat predates by about 1/4 of a century.

    Being one design classes there was a lot of comparative information available between similar but different boat types.

    From memory the Arrow predated the Paper Tiger, both 14 feet LOA. The Arrow had the centreline centreboard. The Paper Tiger had twin through hull boards. The arrow had basic flat bottomed hull forms.

    Both sailed in large fleets. the ARROW WAS FASTER around a course. It had a lower VYC yardstick. Now the Arrow has been much updated over the years and has only got faster. There was other differences in the designs with the PT having a more modern Una rig, better chine hull shape, but no trapeze for instance.

    Now before you start bashing away on your keyboard re this is not definitive data to say single centreline boards are better. We all know that. I suspect in the real world over a range of conditions its Bloody hard to tell.

    Hence CT249 ended his post with "I think"

    There is probably no better way to test ideas than in large one design fleets over time.

    Who would have thought a boomless main could get a start in the "A" s. Or boomless and no traveller. Now that will get some panty wadding issues happening:D
     
  6. brian eiland
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    brian eiland Senior Member

    Boomless,...Stiletto 30 then Stiletto 23. I experienced it, then adopted it for our Firefly trimaran I suggested it to new owner of NACRA at the time, and their next model came out boomless.

    Mainsail-less...that's me :D:D;)
     
  7. DennisRB
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    DennisRB Senior Member

  8. brian eiland
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    brian eiland Senior Member

    another case for Mainsail-less

    Just happened across this interesting little posting about trouble getting that traditional mainsail down in storm conditions.

     
  9. brian eiland
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    brian eiland Senior Member

    Main Sail Less

    I was just going back thru a portion of this subject thread and ran across this older posting (#46) I had forgotten about. I thought it desired repeating since I have tried to emphasize that my pursuit of this rig design is centered around the aging cruiser.

     
  10. brian eiland
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    brian eiland Senior Member

    Another quote from that other forum:
     
  11. brian eiland
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    brian eiland Senior Member

    ...and another...

     
  12. brian eiland
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    brian eiland Senior Member

    ATTENTION Cruising Sailors, interesting website

    Just today a gentleman who has corresponded with me for some time about my aftmast rig sent me a reference to this website.

    http://www.rhbell.com/Simbo/

    His introductory paragraph says a lot:
    Have a look at his site,...interesting...
     
  13. DennisRB
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    DennisRB Senior Member

    I just returned from the BVI. Friends are skippers in the Voyage fleet and I got to tag along. With the all electric winches, mainsail handling is easy. With huge foresails, electric winches would be even more necessary. I saw many of the lagoon aft mast designs. I think they look good. Very slow, but that has everything to do with the weight of the boat and not the rig.

    For anyone that actually likes sailing and wants to charter in the BVI, Voyage seem to be well in front when it comes to performance in a charter cat. My charter friends come from an actual sailing background (unlike many charter captains who have never sailed on anything other that fat charter cats). They say that Voyage boats are like night and day compared to the likes of lagoon etc. I was impressed. We sailed to windward by tacking, and were able to maintain speeds of 10.5K in the 480 on a reach.
     
  14. brian eiland
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    brian eiland Senior Member

    BTW this little note on the cutter rig portion of that website i just posted

    http://www.rhbell.com/Simbo/cutter-rig.html

     

  15. brian eiland
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    brian eiland Senior Member

    I repeat again....

    "The points I was trying to make for my aft-mast rig with its big genoa is that I was trying to meet a big variety of conditions with a limited sail inventory (my 3 sails are the only ones I have onboard, and are set up to be reduced in size by roller furling, not hoisted or replaced by alternatives).

    As such I wanted a good size genoa sail for those often encounter 5-15 knot winds that we would really like to sail in rather than turning on the engine(s). This size sail, in those conditions, should be relatively easy to handle, ...(and when out cruising I would NOT be looking at getting into tacking duals). I was seeking to get the best from this genoa sail by giving it the best help from the 'cutter jib' (mainstaysail as I refer to it), and providing for its best dumping traits as described by Tom.

    I'm also quite convinced that modern sail materials such as the tape-drives or these Titanium sails would allow for a very light weight sail that would maintain their shape even in higher wind conditions. be nice to be able to utilize this reef-able genoa up to the 30 knot range.
     
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