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3017Re: Help with offsets

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  • Billy
    Apr 30, 2011
      Thanks John K. I will build this boat. The more I look at it the more I likes it. You're right, I just need to slow down a bit. I have built several boats before but there was no lofting involved.

      --- In AtkinBoats@yahoogroups.com, "John Kohnen" <jkohnen@...> wrote:
      > I think John Atkin wrote at least once that one should _never_ scale
      > critical dimensions off a plan, only take them from the full-size faired
      > lofting. It's the Truth, whoever wrote it. On the Atkin plans the height
      > of the bottom in the offset table is taken from the baseline, and the
      > height of the sheer is taken from the waterline. Those heights are in the
      > offset table, not on the profile drawing. The profile drawing will show
      > the height of the waterline above the baseline and the spacing of the
      > sections, and will have the dimensions you need to get the shape of the
      > face of the stem right. If there are NO dimensions shown on the profile
      > drawing maybe by mistake Mrs. Atkin sent you a copy of an early draft, not
      > the finished drawing... But I'll bet there's everything you need in the
      > plans, without having to use a scale rule. Just take it slow and easy and
      > everything will begin to make sense as you move along. Start with lofting
      > the profile, then the plan view, and finally the body plan, or sections.
      > Don't forget to deduct the plank thickness when you make your molds.
      > Alas, I can't find a good explanation of lofting on the Interweb. I
      > suppose I should put an old article online myself one of these days...
      > John A's story of lofting his Cabin Boy gives you an idea of what's
      > involved in lofting an Atkin skiff:
      > http://preview.tinyurl.com/3hgqtkr
      > The best book I've seen on the subject is Allan Vaitses's, and if you feel
      > totally lost maybe it'd be a good idea to sit back and wait for the book
      > to be delivered:
      > http://preview.tinyurl.com/6hsdce
      > Lofting is unfamiliar to many amateur boatbuilders today, but it's really
      > not that hard to learn, and not all that complicated for a simple skiff.
      > You'll get there, Billy. Good luck!
      > On Wed, 27 Apr 2011 20:42:08 -0700, Billy wrote:
      > > Oh, specifically, there are no offsets from the bottom of the boat to
      > > the sheerline to tell me the height of each station to make the molds,
      > > there is nothing telling me the distance from the baseline to the load
      > > waterline, there is no offset for the height of station 12, nothing
      > > telling me how high the bottom of the stem is above the baseline, no
      > > information at all about the heights of the transom from any of the few
      > > given reference points and no information about station 0 which
      > > intersects the stem at some point. Like I said there is a lot of
      > > guesswork and scale rule work and figuring to be done to make these
      > > workable plans. I guess my only viable option is to use the scale rule
      > > and loft it as closely as I can and then fair the lines....
      > --
      > John (jkohnen@...)
      > I get up every morning determined both to change the world and
      > to have one hell of a good time. Sometimes this makes planning
      > the day difficult. (E.B. White)
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