Message-Id: <199703122224.OAA18543@ns1.intelenet.net>
From: Wolfgang Brinck <wolfgang.brinck@hksystems.com>
Subject: Re: Articulated keelson
To: baidarka@lists.intelenet.net
Date: Wed, 12 Mar 97 16:19:42 CST
In-Reply-To: <97Mar12.163452est.14729-2@prufire1.prusec.com>; from "carl_vonkleistiii" at Mar 12, 97 5:24 pm
>
> Bill Low wrote:
> >
> > I have a question on cutting the keelson. The last boat I did I tried to
> > follow the drawings in QAJAQ by D. Zimmerly. The drawings and the
> > picture on page 23 shows a vertical cut from the top of the keelson down
> > about 25% then a sloping arc toward the ends of the boat.
> >
> > The problem I experienced with that was when the bow or stern was forced
> > down the outward protion of the keelson rose up and locked in that
> > position. It overlapped the middle section of the keelson. Realizing
> > that this was an extreme case I did not worry about it at the time but
> > it could cause a problem if it did happen in rough seas.
> >
> > Has anyone else had this problem?
> >
> > Would making that first vertical cut at an angle toward the center of
> > the boat rather than at 90 degrees be better. I would think this would
> > make a locking mechanism so the keelson could not ride up and lock in
> > place.
> >
> > Any ideas would be helpful.
> >
> > Thanks
> >
> > Bill Low
>
> I don't have QAJAQ or Baidarka (by Wolfgang Brinck) with me right now,
> but I think I can visualize the problem you are talking about. I am not
> yet to that stage on my boats, but I think that the answer lies in one
> of the pictures in Baidarka. I don't recall whether QAJAQ shows the
> joint lashing at the keelson joints or not, perhaps not if it is just an
> offset type drawing. If I'm not mistaken, this joint should be lashed
> both fore and aft, through holes bored in each keelson piece a few inches
> on either side of the joint; additionally, there should be lashing around
> the joint itself, almost a "whipping" type of lashing like you would see
> on the end of a rope. This should hold the joint in position as it
> flexes. I would hesitate about making a locking joint of any kind
> because that would be in direct contravention of the principle of the
> design. Even if you have the skin already on the boat, you might be able
> to get to the joint to accomplish the lashing.
>
> Hope this helps.
> --
> Eric von Kleist We pray for one last landing
> Hilton Head Island, SC On the globe that gave us birth,
> USA To rest our eyes on the fleecy skies
> And the cool green hills of Earth.
>
I have done the lashing as described and not had problems with
the keelson coming apart. I also try to position the joints so
part of it is supported by a rib. Don't rest the rib against the
lashing to avoid abrasion.
As for retrofitting, I have slit the bottom of the boat and opened a flap
to repair keelson joints, then sewn up the flap, applied a patch and
gone forward.
If your keelson is made of soft wood, fore and aft lashings will saw away
at the lashing holes in time and may require maintenance. Hard use
such as enders in surf will also stress the joint and may call for
maintenance.
--
wolfgang. /|
brinck@h / oo wolf
ksystem / \ wolf
s.com / | wolf
\ / |
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