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PeterSibley
04-29-2003, 06:07 AM
Does anyone out ther have any good info or links to sites showing eliptical stern construction? Thanks all.

Thaddeus J. Van Gilder
04-29-2003, 06:52 AM
I did a sharpie with an eliptical transom once.
I made upper and lower frames, and planked the trnsom up like a barrel. I had to use pretty thick planking stock, though, because those planks (staves?) have to really be backed out!

-Thad

PeterSibley
04-29-2003, 03:48 PM
Thad
I think I can wrap my mind around a sharpie eliptical stern, its the carvel version I'm having trouble with . Maybe I should just build a 1" to the 1" model .

Ken Hutchins
04-29-2003, 08:47 PM
Peter, I had some problems projecting the lines for my transom, pooter screen too small, too many lines too close on paper, so I lofted it full size with many different colors which helped me 'see' what lines went where. Then I updated The pooter file accordingly. smile.gif Chapell's Boatbuilding has a few pages on it along with the following statement "even the better professionals have trouble obtaining the proper shape" :eek:

Dave Fleming
04-29-2003, 09:15 PM
IIRC, eliptical and horseshoe stern construction was a 'bread and butter' type.
Layup layer after layer and fastened with drifts in heavy vessels like fishboats and tugs.
Scantlings would be reduced for smaller craft but the principle remains the same.
Usually a 'knuckle' at the waterline or just above was the transition to the planked remainder of the hull.

Thaddeus J. Van Gilder
04-30-2003, 06:55 AM
Other than the vertical staving, I have seen some old work boats with the "bread and butter" sterns.

They were pretty much blocks of 4 by 8's, maybe 1 foot long, drifted and bolted to each other. It looked ok on a 40 footer...well, not ok, but somewhat workable.
I don't know f it would work on a small boat.

Then again, I recall seeing and article, maybe 5 or 7 years ago in Boatbuilder about someone in the south building boats out of 2 by 4 offcutts epoxyied together. The resulting block of wood was somewhat boatlike in shape, and the dude shaped everything down with an electric plane. lastly it was epoxy and glassed inside and out.

If that could work for a whole boat, maybe it could work for a stern...not on a boat for me , though...

-Thad

PeterSibley
05-03-2003, 04:29 AM
Thanks Dave,
I ran a trial lofting today, just for a rough idea and it seems feasible.It would be a lot better with a few layers of compass timbers wouldn't it, less butts and a lot more strength, getting the deck crown would be interesting.

Dave Fleming
05-03-2003, 10:53 AM
Not much camber to fit to on the stern bulwarks of a workboat.
For a smaller pleasure boat base logs/timbers would be milled thicker to accomodate the loss of material to suit the camber.