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Re: Which offsets are you using?
By:Dean Trexel
Date: 11/4/2001, 9:49 pm
In Response To: Which offsets are you using? (Pete Rudie)

I'm working off of the revised numbers that came with my Fall '94 back-issue that I ordered. I set up the boat in CAD using the form/cradle numbers, and you can see the rocker in the keel numbers -- 0,40 means that the keel as 40mm above the table. I don't have the numbers handy (they're at work) but the middle form if I recall was at 0,15, so the boat is sitting 15mm above the table. To figure the rocker you would have to subtract that 15mm, i.e. the form at 0,40 would have 25mm of rocker. The big assumption I'm making is that the boat is set up correctly horizontally -- that it won't be sitting in the water at a different angle than what the forms show. It's possible that the boat will sit in the water differently than the rocker numbers show. I have yet to make a complete volume out of the hull in CAD. Once I've done that, I can analyze how much volume is fore and aft of the CG of the combined boat/paddler. It may be that the cockpit needs to be moved slightly aft, like the Seguin. Or possibly I decrease the rocker a bit at the stern.

Are you going to be building the Sea Kayaker boat this winter, Pete? I have the panels and forms in CAD and can send you full-sized plots if you like. Could even send you a scaled down version if you want to make a model or something. :)
My reason for doing all of this in CAD is that I was hoping to make a stripped version. And dadgumit if Paul G. Jacobsen didn't think of it first (again!). He recently posted that he'd thought about making a stripped version of a stitcher by making stripped panels, cutting them to shape, glassing one side, and stitching it together. (Actually, if memory serves, someone actually did this a couple years ago and posted pictures here.) I plan on making station forms and stripping as usual on a strongback, because I want the hull side strips to follow the shear. Making panels and cutting the panels out of them would leave an odd-looking intersection between panels. If I strip it as usual, I can put a strip at the shear, a strip at the chine, and do cheater strips to make a nice transititon. Stripping on forms will still be a quick job, though, because there will be no need for cove-and-bead or any beveling between strips on the hull. The only area on the deck that will need beveling is the area over your legs -- the rest of the deck I plan on making flat.

And if all of this goes as planned, I need to set me up a website, too...

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