Boat Building Forum

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Re: corrupted curvature
By:Toni V
Date: 9/19/2007, 6:49 am
In Response To: corrupted curvature (mike allen)

: I brought it up about a year ago in the freeship development forum, with no
: response. As this (curvature always going to zero at endpts - (and
: intersections are similar) is specifically referred to in the freeship
: manual, i assume there is something fundamental going on. I brought
: another issue up with the present ‘plus’ developer, but it seems he is
: pretty focused on the holtrop method for now. Maybe it’s time to email him
: again.

I too have found lot's of strange things in development for panels. I also think I posted some issues to Freeship board way ago.

One is that if you make a new boat (just do the new usual boat) and check the panel developable and it shows no errors in developability for the round chined boat! Error values are great and 3d-developability shows all red, but the developability window shos no problem.

Another is that undevelopable hard angles are sometimes shown as developable.

: I remember discussing on the greenland board (topic about making reference
: boats from KOG) - that you have to be careful converting the reference
: yaks to s&g. as IF you join a panel to the nice gunwale (or any existing
: line), the gunwale will now have a hard point and that part of the curve
: will splay outward (regardless of whether points are ‘locked’ or not).

Yes, the controlpoints are defining the shape and more points - the closer the shape will be to the points. I guess that's the idea of using controlpoints and not using real "hard points". In simple kayaks, adding a full deck to chine is not usually problem but adding a half deck is a problem because the shape is no longer the same. I'm guessing in multipanel kayaks like yours, this can be a real problem.

: less points making the curve, the more it will be outa whack. (That’s why
: I think that the ref boats should be also be done as markers so that the
: known shape can always be referred to – not that anyone couldn’t quickly
: do it anyway with what was used, I guess)

Sorry, I didn't understand this one. I would think that the less points the better, flowing shape, can be produced. Of course the less controlpoints needs to be more far from the actual shape. But if a desired real hull shape is created with less controlpoints would there be any difference when using more controlpoints? And just assuming the controllpoints are placed well across the panels.

Messages In This Thread

S&G: Delftship panel shape development *LINK* *Pic*
Dave Reekie -- 9/3/2007, 4:35 am
Just a thought...
Jay Doorly -- 9/4/2007, 12:02 am
Re: S&G: Delftship panel shape development
Bryan Hansel -- 9/3/2007, 1:59 pm
Re: S&G: Delftship panel shape development
Bryan Hansel -- 9/3/2007, 2:05 pm
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/3/2007, 2:12 pm
Re: S&G: Delftship panel shape development *Pic*
Duane Strosaker -- 9/3/2007, 1:26 pm
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/3/2007, 1:37 pm
Re: S&G: Delftship panel shape development
HenkA -- 9/3/2007, 9:53 pm
Re: S&G: Delftship panel shape development
Robert McMurray -- 9/4/2007, 10:33 am
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/4/2007, 11:14 am
Re: S&G: Delftship panel shape development
Robert McMurray -- 9/4/2007, 11:46 am
Re: S&G: Delftship panel shape development
Bill Hamm -- 9/5/2007, 2:19 am
Re: torture *Pic*
Robert McMurray -- 9/6/2007, 12:19 am
Re: S&G: Delftship panel shape development
Toni V -- 9/4/2007, 2:43 am
Re: S&G: Delftship panel shape development
HenkA -- 9/4/2007, 10:08 am
Re: S&G: Delftship panel shape development
Nick Schade - Guillemot Kayaks -- 9/4/2007, 11:01 am
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/4/2007, 4:26 am
Re: S&G: Delftship panel shape development
Bryan Hansel -- 9/4/2007, 12:14 am
Re: S&G: Delftship panel shape development
HenkA -- 9/4/2007, 12:37 am
Re: S&G: Delftship panel shape development
HenkA -- 9/5/2007, 12:41 am
Re: S&G: Delftship panel shape development
David Reekie -- 9/8/2007, 8:11 am
Re: S&G: Delftship panel shape development
Bill Hamm -- 9/12/2007, 4:53 am
bending ply *Pic*
mike allen -- 9/12/2007, 11:57 am
Re: bending ply
Bill Hamm -- 9/16/2007, 3:20 am
Re: bending ply
Bryan Hansel -- 9/12/2007, 1:30 pm
s&g (developable) surf kayaks *Pic*
mike allen -- 9/12/2007, 2:23 pm
Re: s&g (developable) surf kayaks
Bryan Hansel -- 9/12/2007, 11:54 pm
another s&g (developable) surf kayak: *Pic*
mike allen -- 9/13/2007, 1:30 am
Re: another s&g (developable) surf kayak:
Bryan Hansel -- 9/13/2007, 7:13 pm
a s&g freeship surf kayak - the 'rail' *Pic*
mike allen -- 9/14/2007, 1:33 am
Re: a s&g freeship surf kayak - the 'rail'
Bryan Hansel -- 9/15/2007, 7:45 pm
some freeship techniques *Pic*
mike allen -- 9/16/2007, 3:46 am
Re: some freeship techniques
Bryan Hansel -- 9/17/2007, 5:04 pm
more freeship techniques *Pic*
mike allen -- 9/18/2007, 2:33 am
Re: more freeship techniques
Bryan Hansel -- 9/18/2007, 9:11 pm
control curve vs actual shape curve
mike allen -- 9/18/2007, 9:46 pm
Re: more freeship techniques
Bryan Hansel -- 9/18/2007, 9:07 pm
Re: more freeship techniques
Nick Schade - Guillemot Kayaks -- 9/18/2007, 8:56 am
corrupted curvature
mike allen -- 9/18/2007, 3:32 pm
Re: corrupted curvature
Toni V -- 9/19/2007, 6:49 am
Re: corrupted curvature
mike allen -- 9/19/2007, 2:42 pm
Re: corrupted curvature
Toni V -- 9/20/2007, 6:11 am
Re: corrupted curvature
mike allen -- 9/20/2007, 7:39 am
Re: corrupted curvature
Bill Hamm -- 9/18/2007, 6:43 pm
Re: corrupted curvature
Nick Schade - Guillemot Kayaks -- 9/19/2007, 12:56 pm
Re: corrupted curvature
HenkA -- 9/19/2007, 8:26 am
the magic *Pic*
mike allen -- 9/19/2007, 12:41 am
Re: Somebody has to ask....
TOM RAYMOND -- 9/19/2007, 12:16 pm
Re: Somebody has to ask.... *Pic*
mike allen -- 9/20/2007, 3:02 pm
Re: Somebody has to ask....
TOM RAYMOND -- 9/20/2007, 4:32 pm
some are a little more normal *Pic*
mike allen -- 9/21/2007, 3:58 am
Re: some are a little more normal
Bryan Hansel -- 9/21/2007, 8:33 am
Re: some are a little more normal
mike allen -- 9/21/2007, 12:16 pm
freeship sketch version of 'solitude 15' *Pic*
mike allen -- 9/22/2007, 6:33 am
freeship 'solitude 15' - 90 deg panel twist
mike allen -- 9/25/2007, 2:07 pm
Re: a s&g freeship surf kayak - the 'rail'
Ken Blanton -- 9/14/2007, 7:00 am
Re: a s&g freeship surf kayak - the 'rail'
mike allen -- 9/14/2007, 5:03 pm
'la ligne' - another s&g freeship surf kayak *Pic*
mike allen -- 9/14/2007, 2:18 am
Re: S&G: Delftship panel shape development
Bryan Hansel -- 9/5/2007, 1:09 pm
freeship is still continuing - at vers 2.78
mike allen -- 9/4/2007, 12:08 pm
Re: freeship is still continuing - at vers 2.78
Dave Reekie -- 9/4/2007, 1:43 pm
freeship stuff + vers 2.78 link *LINK*
mike allen -- 9/4/2007, 3:13 pm
Re: freeship stuff + vers 2.78 link
Toni V -- 9/5/2007, 4:04 pm
Re: freeship stuff + vers 2.78 link
mike allen -- 9/5/2007, 4:31 pm
Update *LINK* *Pic*
David Reekie -- 9/8/2007, 8:39 am
Update comments
mike allen -- 9/10/2007, 1:26 pm
Re: Update comments
Toni V -- 9/11/2007, 7:55 am
Re: Update comments
mike allen -- 9/11/2007, 11:55 am
Re: S&G: Delftship panel shape development
Toni V -- 9/3/2007, 10:27 am
Re: S&G: Delftship panel shape development
HenkA -- 9/3/2007, 9:42 pm
Re: S&G: Delftship panel shape development *Pic*
Robert McMurray -- 9/3/2007, 1:15 pm
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/3/2007, 1:23 pm
Re: S&G: Delftship panel shape development
Robert McMurray -- 9/3/2007, 3:13 pm
Re: S&G: Delftship panel shape development
Dave Reekie -- 9/3/2007, 1:14 pm
Re: S&G: Delftship panel shape development
Toni V -- 9/3/2007, 2:47 pm
Re: S&G: Delftship panel shape development *LINK*
Daren -- 9/3/2007, 8:46 am