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Taking lines

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stevej

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Apr 8, 2002, 8:46:10 AM4/8/02
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I need to take off lines from a small boat (15 ft) and want to do it as
efficiently and
accurately as possible.
Does anyone know of a source online that describes a method?
I've seen a few descriptions but most are quite general.
I'll be working indoors, inside a museum so the methods that use stakes
driven
into the ground need to be modified. I'm aware of the WOODENBOAT
publication
archives and would like to examine several other options/techniques to
see if they
might be combined to produce a method that works extremely well.


Cliff W Estes

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Apr 8, 2002, 10:32:48 PM4/8/02
to
Several methods are available. Unless you have the time to learn some new
technology, I would suggest the following:

Locate the hull on a flat level floor.

Build a "Bridge" - an arch which goes from one side of the boat to the
other, with grid marks on it, representing evenly spaced buttocks. These
buttocks should be closely spaced enough that no station will yield an
insufficient number of measurement point.s

Set the boat on horses bottom side up.

Level the keel or some other feature which is supposed to be level. If
nothing else, determine how much drag there is to the keel and set the hull
up so that the keel has the proper amount of drag.

Construct a series of stations along the length of the hull. Make these
perpendicular to the centerline.

In succession, move the bridge to each of these stations and take
measurements at any edges (skeg/hull, chine, sheer) and at all buttocks on
the bridge, which yield offsets
(some will be beyond the half-breadth of the sheer, particularly at the
ends).

Take measurements at each buttock and to each edge. In the case of an edge
(the sheer, for example), hang a plumb bob such that it just touches the
sheer and measure not only the vertical dimension, but also the dimension
from the closest buttock to the plumb line.

I use more modern technology involving an Electronic Distance Meter
(Theodolite and data collector). The instrument gives me x,y and z in feet
and decimals to an accuracy of 1/8" over a couple of hundred feet, although
such a measurement is seldome necessary, since you can rarely see that much
of the boat from a couple of hundred feet away. This technology has been
used to measure boats as small as a Bristol Bay Gillnetter to a 240-foot
stern trawler.

Hope this helps.
--

Cheers,

**********************************************************************
*** Cliff W. Estes ces...@basline.com ***
*** BaseLine Technology ph (425)882-7317 ***
*** 15834 NE 67th Place fax (425)882-7327 ***
*** Redmond, WA 98052 http://www.basline.com/ ***
**********************************************************************
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"stevej" <myh...@sover.net> wrote in message
news:3CB19111...@sover.net...

Stephen Baker

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Apr 8, 2002, 11:31:54 PM4/8/02
to
The preferred method, for those who are wealthy (and generous) enough, is to
support your local designer/documenter and pay _him_ to do it for you.
;-)

Steve
Stephen C. Baker - Yacht Designer
http://members.aol.com/SailDesign/private/scbweb/home.htm

Cliff W Estes

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Apr 10, 2002, 2:19:28 AM4/10/02
to
Er, yes, but I got the impression from his post that he wanted
recommendations on how to do it, not how to have it done for him. :-)


Cheers,

**********************************************************************
*** Cliff W. Estes ces...@basline.com ***
*** BaseLine Technology ph (425)882-7317 ***
*** 15834 NE 67th Place fax (425)882-7327 ***
*** Redmond, WA 98052 http://www.basline.com/ ***
**********************************************************************
Hydrostatics from Rhino using RhinoStatics
http://www.basline.com/rhinoplugin
Quality Marine Fairing, Modeling and Rendering
http://www.basline.com/imggal.shtm


"Stephen Baker" <saild...@aol.comnospam> wrote in message
news:20020408233154...@mb-cc.aol.com...

Backyard Renegade

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Apr 10, 2002, 4:55:00 AM4/10/02
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stevej <myh...@sover.net> wrote in message news:<3CB19111...@sover.net>...

For a small boat like this, I would reccomend "The Dory Book" by John
Gardner. There is a section on lofting and stuff that will explain it
pretty well. It's pretty simple really, the hardest part is building a
frame or something from which to get your reference points..
Scotty

Michael Porter

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Apr 10, 2002, 6:46:04 AM4/10/02
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There is a book called "Boats: A Manual for their Documentation"
published by the American Association for State and Local History.

The modern (faster) way to do this is with a surveyor's total station,
but that is expensive and requires some fairly expensive software to
make it work

Michael Porter Naval Architect / Boatbuilder
mporter at mp-marine dot com
www.mp-marine.com

Stephen Baker

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Apr 10, 2002, 7:11:03 AM4/10/02
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Cliff W Estes writes:

>Er, yes, but I got the impression from his post that he wanted
>recommendations on how to do it, not how to have it done for him. :-)

I guess I'm going to have to put <tongue-in-cheek> tags on my posts in future,
right? ;-)

Steve

stevej

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Apr 10, 2002, 10:58:13 PM4/10/02
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The bridge idea with the buttock lines seems to make a lot of sense.
That's probably how i will do it.
Thanks

stevej

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Apr 10, 2002, 11:04:22 PM4/10/02
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Thanks for the suggestion.
Unfortunately there is NO budget for this project.
It is being done for the enjoyment and appreciation of historic small
watercraft.
Since I somewhat understand the process and have lofted several boats, I was
thinking that this little canoe would be possible to do without a degree in
nautical
arhitectural design and engineering. I could be wrong..
I was looking more for a methodical procedure and apparatus (frame or something)

to assist in getting it accurate.

stevej

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Apr 10, 2002, 11:05:45 PM4/10/02
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Yes, Ive seen this once I think...I will check it out. Thanks
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