651Re: Atkin plans, how much detail and what come with them
- Apr 27, 2005Thank you for the answers about the plans.
To answer your question about strip planking then cold molding over
the top of that, I would first take small strips that had a bull
nose profile on one side and a fitting hollow on the other. You
have to put in sub frames to get the curve of the boat right when
doing this. They are removed after strip planking is done. You use
epoxy to glue down each strip so that there are no holes and you can
even use white oak strips on the bottom and red cedar from the
waterline up. I have been experimenting and when you add a new type
of dye to the epoxy it looks like small stripes between the wood
strips of any color you wish and the interior looks great where it
has to be exposed when this is done. They even make gold metal
flake dye if you want to get very fancy. On any type of laminations
it looks dynamite also. Especially knees
Once all the strips are in place you cold mold the hull by placing
veneer at 90% angles across each other in two different layers sort
of like a radial tire. Then final layer of veneer that lays front
to back. these layers are made from western red cedar and if you
only use cold molding it can be as light as a carbon fiber craft.
The strip planking gives a little more material to epoxy the cold
molding strips to, plus it makes the inner frames work like the
designer wanted so the boat is much stiffer than just cold molding.
So you can't get 1/2" strips 45' long but you can finger joint the
strips before you run them through the router to put the bull nose
and hollows on them. That way the finger joint is much stronger than
a plain scarf joint with about four times the glued surface. When
you epoxy then down you can use string to make them stay tied down
or you can use a nail gun with the settings so the 18 gauge brad is
still above the surface and is pulled out before you cold mold over
that. It takes more time to build like this but it is much less
expensive in the long run.
When you cold mold the veneer down you use staples but they are also
pulled and the hole epoxied over before the next layer is put down.
They make very fair hulls and the weight is tons lighter than
planking a hull. In fact that is the way companies make moulds for
fiberglass hulls. They make a male hull then cover it with plastic
and make a female hull from the first hull like I will be making.
They then fair the inside of the female mould with bondo to make is
glass smooth then they can build a plastic boat inside of that.
Many catamarans are made by cold molding the hulls and next to
carbon fiber which by the way must bake in a giant oven is the
lightest way to build any hull. They have giant sloops over 150'
lon built from the cold molding process The red Cedar with epoxy
stops any type of marine borer from eating wood hulls in the
southern latitudes. Marine borers just love planked boats unless
you use anti fouling paint and fiberglass sheeting Even then when
you rub the dead wood on a coral head or sandy beach you rub off
your protection and marine borers can eat a doug fir boat in one
season of tropical sailing. A very good book to read about Cold
Molding is by John Guzzwell. The Book's name is Modern Wooden Yacht
Construction , cold molding, Joinery and Fitting Out. He actually
built a Jay Benford double ended boat that is a near cousin to the
Atkin Eric. Jay references the Atkin's double enders often. The
35' cold molded motor sailer that John Guzzwell builds uses more
lead ballast in the keel because the whole boat is so much lighter.
You have more weight to use for fuel and supplies not to mention
better speed and no bilge water leaking from stuffed seams. Being
completely sealed from moisture the red cedar stays in place and the
hulls when they are on the hard being painted don't shrink and leak.
William Atkin died just before cold molding became popular but I am
sure with his shallow draft tunnel hulled boats he would have been
delighted to see a material that could make the type of bends and
curves needed to make those hulls work their best and very easy for
a home builder to use.
--- In AtkinBoats@yahoogroups.com, DirtSailor <dirtsailor2003@y...>
> I must inquire as to what kind of strip built we are
> refering too. My assumption from the original post
> would be that the inner layer would be stripped then
> sheathed over much like a stripper canoe. The second
> post sounds more like plank on frame, with a form of
> caulking, may it be cotton, Sika or otherwise, between
> the planks which when full of water swell up and seal.
> Are these assumptions correct?
> As for the plans, The plans for Trim that I purchased
> include the original article, boy I wish the bill of
> materials still cost what is listed! Any one have
> plans fora time machine? All the other information
> needed to build the boat is there, however, it does
> require full lofting, so one would need to be skilled
> in laying down lines. I must say that the
> Draftsmanship is superb. I work in the residential
> design business and since the advent of computers I
> know I couldn't draft like that anymore. It is my
> opinion that the price of the plans are well worth
> what is there.
> Do You Yahoo!?
> Tired of spam? Yahoo! Mail has the best spam protection around
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