Re: 18 ft Clam Skiff from Boats with an Open Mind
--- Inbolger@yahoogroups.com, "escottw55" <scottw@m...>
wrote:
Payson according to his wishes. Payson likes to push row
standing up. He uses oarlock on posts. The narrower boat
would be better for rowing. Bolger does believe in matching the
side curvature to the bottom rocker in these flat bottom designs.
He also like to design for the least possible waste of material.
Vince
wrote:
> WhatI was wondering was if there was any theoretical orempirical
> analysis that went into deciding the beam of the boat, and/orthe
> width and depth of the shoe ?I don't know except that Bolger designed the boat for Dynamite
Payson according to his wishes. Payson likes to push row
standing up. He uses oarlock on posts. The narrower boat
would be better for rowing. Bolger does believe in matching the
side curvature to the bottom rocker in these flat bottom designs.
He also like to design for the least possible waste of material.
Vince
--- Inbolger@yahoogroups.com, "soussouchew" <vachew@v...> wrote:
legs up against the sides. The last one I used worked great (clamming)
but it was 16 ft with 7 ft beam and flat bottom so if it dove down a
wave and buried the bow it would yaw like crazy. Never sunk though.
So I can see why he would want a narrower hull.The one before that
was 20' LOA with a 7-1/7 beam and it didn't have that same behaviour.
Nice sheer too except (as Bolger said) they swamp from the stern
quarters. The guy I bought that one from had basically built 6 inch
high bulwarks on the back six feet of the sides to stop it from
swamping.
I like your idea about coming back later and adding thickness to the
shoe if I think I need it. Sounds pretty easy.
I think I can widen the boat by simply widening the stem 6 inches and
adding 3 ins to each half breadth offset including the transom. By
doing that I can use the same side panels. I read an article in PBB
about a boatbuilder who builds these hi-tech sailboats and they
shaped all the way from the fore bulkhead to the cutwater with PVC
foam and glassed it. Then they attached it to the fore bulkhead,
faired it in and glassed it.
WhatI was wondering was if there was any theoretical or empirical
analysis that went into deciding the beam of the boat, and/or the
width and depth of the shoe ?
> If you widen the boat, you lose the convenience of the flat panelThe boats I used did have plumb sides. Gotta have 'em to brace your
> expansions. You could probably use the offsets to loft from, but
> the spacing would change.
>
> Before you decide, consider whether the skiffs from your past
> clamming had flare in the sides (which clam skiff does not). If
> so, they may have been no wider on the bottom than the clam
> skiff.
>
> There is no box keel on the clam skiff. There is a SHOE formed
> by multiple layers of plywood laminated onto the inch thick
> bottom. If you use the 3 layers shown in the plan, this makes the
> bottom 2-1/2" thick in way of the shoe. If, after using it as
> designed for a while, you feel you need more lateral plane for
> "carving turns" you could easily add an additional layer or two.
>
> Vince Chew
legs up against the sides. The last one I used worked great (clamming)
but it was 16 ft with 7 ft beam and flat bottom so if it dove down a
wave and buried the bow it would yaw like crazy. Never sunk though.
So I can see why he would want a narrower hull.The one before that
was 20' LOA with a 7-1/7 beam and it didn't have that same behaviour.
Nice sheer too except (as Bolger said) they swamp from the stern
quarters. The guy I bought that one from had basically built 6 inch
high bulwarks on the back six feet of the sides to stop it from
swamping.
I like your idea about coming back later and adding thickness to the
shoe if I think I need it. Sounds pretty easy.
I think I can widen the boat by simply widening the stem 6 inches and
adding 3 ins to each half breadth offset including the transom. By
doing that I can use the same side panels. I read an article in PBB
about a boatbuilder who builds these hi-tech sailboats and they
shaped all the way from the fore bulkhead to the cutwater with PVC
foam and glassed it. Then they attached it to the fore bulkhead,
faired it in and glassed it.
WhatI was wondering was if there was any theoretical or empirical
analysis that went into deciding the beam of the boat, and/or the
width and depth of the shoe ?
If you widen the boat, you lose the convenience of the flat panel
expansions. You could probably use the offsets to loft from, but
the spacing would change.
Before you decide, consider whether the skiffs from your past
clamming had flare in the sides (which clam skiff does not). If
so, they may have been no wider on the bottom than the clam
skiff.
There is no box keel on the clam skiff. There is a SHOE formed
by multiple layers of plywood laminated onto the inch thick
bottom. If you use the 3 layers shown in the plan, this makes the
bottom 2-1/2" thick in way of the shoe. If, after using it as
designed for a while, you feel you need more lateral plane for
"carving turns" you could easily add an additional layer or two.
Vince Chew
expansions. You could probably use the offsets to loft from, but
the spacing would change.
Before you decide, consider whether the skiffs from your past
clamming had flare in the sides (which clam skiff does not). If
so, they may have been no wider on the bottom than the clam
skiff.
There is no box keel on the clam skiff. There is a SHOE formed
by multiple layers of plywood laminated onto the inch thick
bottom. If you use the 3 layers shown in the plan, this makes the
bottom 2-1/2" thick in way of the shoe. If, after using it as
designed for a while, you feel you need more lateral plane for
"carving turns" you could easily add an additional layer or two.
Vince Chew
I dug clams from similar boats for many years. Never worked out of
one so narrow though. I'd like to build one and widen it about 6
inches.
Construction and lofting changes are simple but how do you think it
will change the performance? The photo in the book suggests that as
designed it can carve a turn somewhat. If I widen it do you think I
should modify the box keel a bit and if so how ?
one so narrow though. I'd like to build one and widen it about 6
inches.
Construction and lofting changes are simple but how do you think it
will change the performance? The photo in the book suggests that as
designed it can carve a turn somewhat. If I widen it do you think I
should modify the box keel a bit and if so how ?