Subject: Re: baidarka bow/prow design of a kayak
From: wolfgang brinck (nativewater@yahoo.com)
Date: Fri Feb 16 2001 - 17:37:01 EST
Wouldn't pushing the bow wave further back also reduce
the effective water line length of the boat and limit
top theoretical speed?
Wolfgang
--- Douglas Ingram <redcanoe@pangea.ca> wrote:
> In general, keeping the entry waterlines clean and
> gentle is a pretty sure
> way to go. If you make them too sharp, you are only
> delaying the widening
> of them to further back in the boat, making a
> blunter shape. If you wish to
> make concave entry watelines, I would suggest
> keeping them to a modest
> amount of concavity. I feel that the biggest
> advantage of fine entry lines
> has less to do with simply parting the waterflow
> around the hull, and more
> to do with reducing the bouyancy of the bow that is
> trying to climb the bow
> wave, theryby maintaining a more level trim.
>
> Douglas Ingram
> Red River Canoe & Paddle
> Lorette, Manitoba
> ----- Original Message -----
> From: Douglas and Leticia <huftdecruz@earthlink.net>
> To: <baidarka@lists.intelenet.net>
> Sent: Thursday, February 15, 2001 2:21 AM
> Subject: Re: baidarka bow/prow design of a kayak
>
>
> > I am trying to spend more time really surfing and
> or building my new boat
> so
> > I will keep it short.
> > I have not kept up with commercial boat trends
> very well, however I cant
> > help but to notice the boats built by Necky that
> appear to have a concave
> > shape to their bow resulting in a fine entry at
> the waterline and a fuller
> > buoyant planing sort of shape up at the top (near
> the gunwales). This
> shape
> > is not entirely unlike the bow of a typical Aleut
> baidarka if you imagine
> > the split being filled in(on the baidarka). Have
> you ever tried to
> stretch
> > a material into a concave shape? I think that is a
> pretty good excuse for
> a
> > bifurcated bow. Others might point out the
> similarities to the bows of
> > super tankers and the concept of canceling out a
> bow wave with your other
> > bow wave.
> > As far as Greenland boats are concerned, It seems
> to me that the cross
> > section of a Greenland bow would look like a
> triangle, now just gradually
> > stretch out the point at the bottom of the
> triangle on a diagonal
> trajectory
> > upward(making the most out of the skinny/pointy
> part of the triangle/keel)
> > till you create a point and you will also end op
> with a fine entry and
> some
> > volume up top. Unfortunately you will have a
> longer boat with a relatively
> > shorter waterline compared with the Aleut design.
> > My new boat in the works should offend or appeal
> to purists who favor
> > either design. Its only 14 ft long so that it will
> be more fun to
> > surf/rockgarden paddle with all those folks who
> paddle Coasters into those
> > tight spaces or big waves on the open coast here.
> It has an upturned lower
> > jaw with a fat(wide) upper lip and a typical Aleut
> stern shape. The
> > departure from the typical Aleut craft is in its
> extra full bow, tubby 22"
> > beam, short 14' length, low flat back deck/raked
> cockpit to facilitate
> > rolling and such and last but not least a very
> pronounced single hard
> chine
> > for carving a turn whether on a wave face or windy
> crossing(absolutely NO
> > rudder thanks). The main problem with it is that
> it will be slow, but not
> as
> > slow as a coaster. I am not too concerned since I
> already have a 18' long
> > 19" wide straight jawed baidarka.
> > Incidentally my first boat was a "sleek" Greenland
> style boat and the
> first
> > time I saw an Aleut type boat I thought it was
> quite ugly but somehow they
> > grew on me . Check out some of the bifurcated
> Aleut boats that have a
> > straight lower jaw that doesn't curve up, you
> might like that design even
> > though you have to be careful not to plow too big
> a furrow into the beach
> > when landing straight-on in surf.
> >
> > Doug(who has only built aluminum frame baidarkas
> to date but is looking
> > forward to building a wood framed boat in the
> future.
> >
> > -
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