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Which offsets are you using?
By:Pete Rudie
Date: 11/4/2001, 12:54 am

I just wrote off for a copy of the Fall '94 issue that has the S&G article, and received with it a revised table of offsets. Presumably the numbers in the original magazine article have some errors.

: I'm in the process of putting the Chris Cunningham/ Sea Kayaker stitch-n-glue
: kayak in 3-D using my CAD software at work. I had plotted all the panels
: in 2-D a while back, but am just now trying to work those flat panels
: 'virtually' into the 3-D shape of the kayak. Things are going well
: (although slow), but I came across something odd. The forewardmost form
: shows a rocker of 30mm -- about 1-3/16". The rearwardmost form shows
: a rocker of 55mm -- about 2-3/16". Both of these forms are at the
: point where the keel starts to roll upward into the stem and stern, so the
: locations of these rocker values are accurate.

: Long story short: there is 1" more rocker in the stern than in the bow.
: I've only seen one of these kayaks in person, and the owner had made a
: fixed skeg out of fiberglass about 1-1/2' long and about 1" deep at
: the stern, because he didn't build it with the retractable skeg that was
: included in the instructions and apparenly found out after-the-fact that
: it didn't track as well as he would have liked.

: I thought that Greenland kayaks were made fairly symmetrical so that they
: handled running with and into the wind equally well. And if anything, the
: non-Greenland kayak designs I've seen had less rocker at the stern than at
: the bow.

: I'm not sure how (or if) I'll fix this, I just thought I'd post this finding
: in case there are others out there considering building this kayak. The
: Seguin might be worth a harder look.

: Dean

Messages In This Thread

Cunningham/Sea Kayaker stitch-n-glue design flaw?
Dean Trexel -- 10/25/2001, 1:42 am
Re: Cunningham/Sea Kayaker stitch-n-glue design fl
Pete Rudie -- 11/6/2001, 8:43 pm
And now for a word from the designer...
Pete Rudie -- 11/7/2001, 12:38 pm
Re: Cunningham/Sea Kayaker stitch-n-glue design fl
Dean Trexel -- 11/6/2001, 8:55 pm
Well, there you go, pilgrim... *NM*
Pete Rudie -- 11/6/2001, 9:27 pm
Which offsets are you using?
Pete Rudie -- 11/4/2001, 12:54 am
Re: Which offsets are you using?
Dean Trexel -- 11/4/2001, 9:49 pm
Re: Which offsets are you using?
Pete Rudie -- 11/5/2001, 12:15 pm
Re: Which offsets are you using?
Pete Rudie -- 11/4/2001, 1:26 pm
Re: Cunningham/Sea Kayaker stitch-n-glue design fl
Hans Friedel -- 10/26/2001, 6:23 am
Re: Cunningham/Sea Kayaker stitch-n-glue design fl
Richard Boyle -- 10/25/2001, 8:57 pm
Re: flaw vs. feature?
Mike Hanks -- 10/25/2001, 10:34 am
Re: flaw vs. feature?
Pete Rudie -- 11/4/2001, 1:35 pm
Inherent design feature
West -- 10/25/2001, 3:18 am