Halibut by Arne Kverneland

16 May 2021 18:32 | Anonymous member (Administrator)

The lines plan shows Halibut being symmetric fore and aft of the central main frame (stn. 2), just like a shuttle ferry. I found no reason for not doing it like this, and the design and building will be faster this way. The way the curves along the panels run, also saves time when building. When plank no. 2 (bottom side) has been lofted and cut out, it can be used for scribing the lower edge of the topsides and for the side edges of the bottom plank. Only the sheer line has to be lofted in addition.

As for the 3-panel “Halibut Special” JR, I am quite confident that this will work. After all, it is mainly a top section of a JR, which I am fairly familiar with. The whole idea with it is that the lowered sail bundle can be brailed up with the topping lifts and stowed flush with the mast. The rig can then be lowered for easy stowing  -  and easy rigging again.

That sail has been made very small, to bring the mast length down to 2.5m. I would not be afraid of scaling this rig up to 3-4sqm with the same number of panels. If that mast is lengthened from 2.5 to 3.0m (20%) and the sail is also expanded accordingly, the sail area would end at 3.6sqm (the sail of the Optimist dinghy is 3.3sqm).



Comments

  • 18 May 2021 08:02 | Anonymous member
    I think I like this dinghy best of all (though if David would submit his 5-plank mini-siblim I would find it hard to choose between the two). But. Sorry. That centreboard simply isn't practical in my opinion. If I were building this dinghy I would put a conventional daggerboard case, centrally mounted just in front of the forward thwart and supported by it. Taking into account the innovative rig, this dinghy should be the winner by a mile - except for that centreboard position.
    Link  •  Reply
    • 18 May 2021 14:41 | Anonymous member (Administrator)
      Graeme,
      I am not much worried about that forward-set CB with the CB. slot open in the bow transom. In case it doesn't work, that CB case has not ruined the boat, and the board can be fitted somewhere else, for instance between to the main and fore thwart, and offset almost to the edge of the bottom panel.

      In case the bow CB. works - how fun that would be!

      Anyway, I need a sailing rig for my tender no more than I do for my wheel barrow...

      However, that 3-panel rig (scaled up to 4sqm) would be fine as an aux rig on a 15' færing...
      Link  •  Reply
      • 18 May 2021 22:20 | Anonymous member
        I'm sure it will work all right. On a bigger boat it would indeed be interesting to try an extreme forward-placed centreboard. But I don't think it is practical on this little boat. You need to be able to manage a centreboard with one hand while seated amidships - why place it out of reach when a conventionally-placed daggerboard would work perfectly well with Halibut's layout? It won't fully raise without being attended to, and what's the fun in having to kneel, lean forward and reach over the bow in a tiny little dink like this? I'm all for breaking convention, but in this case what's the point? I'm exercised by this, because I think its such a clever and neat little design in every other respect.

        (I agree about the wheelbarrow – that was just a joke. A pair of little click-up wheels on the transom is the easiest arrangement for a little dinghy, but at 8’ it should be easy enough to just carry it turtle-fashion.)

        As for the rig – I’d like to try one. It might turn out be the “Concept of the Year” for 2021.
        Link  •  Reply
  • 19 May 2021 10:06 | Anonymous member
    This is a nice shape for for a rowing dinghy - but not necessarily for a cruising yacht's tender, which needs more stability for boarding in difficult conditions. The 3-plank sampan with a wide bottom is better for that.
    And, of course, the forward centreboard is a complete non-starter in a yacht's tender, fun though it might be to try it out and see whether or not it works.
    The thwarts are much too close together for me, and I'm not particularly tall. I need one metre from the forward edge of the centre thwart to the forward edge of the after thwart.
    Link  •  Reply
    • 19 May 2021 10:07 | Anonymous member
      The rig, though, is a winner.
      Link  •  Reply
      • 19 May 2021 23:02 | Anonymous member (Administrator)
        David, I am only partly with you there.

        Of course, for maximum stability and use with inexperienced guests, a 3-plank tender will beat a five-plank version. However, 'Halibu't is far from the worst. Being built like a shuttle ferry, it has good sections for stability all the way to the ends.

        As for interior, thwarts etc., my suggested layout is only half-hearted since most builders will install their favourite layout anyway. That’s why I suggest a permanent frame on the middle, so as not to depend on that middle thwart for keeping the shape of the topsides.
        The middle thwart could therefore well be replaced with a saddle thwart.
        The aft thwart could very easily be made to hinge up against the buoyancy bulkhead, giving all the legroom needed for a single rower. With two on board, the rower would either slide forward on that saddle or sit on the forward thwart. With three on board, it will be cramped for sure. I think the trick is to sit a bit sideways for the rower. The aft passenger would move out to one side, and the forward passenger would move to the opposite side.

        Cramped, not comfortable, that’s the name of the game with three men in an eight-foot tender. For ferrying between the shore and the yacht, it may - or may not be found to be good enough. That’s why there are so many inflatables with motors on around...
        Arne
        Link  •  Reply
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

                                                              Site contents © the Junk Rig Association and/or individual authors

Powered by Wild Apricot Membership Software