[bolger] Doubling the Light Scooner!
Realize that when you double the length, the volume will be cubed and
surface area squared. Displacement (and therefore material requirements)
may be cubed. Forces on the rig and hull appendages will increase
geometrically, too. Will standard lumber sizes still work? Hardware?
What about those aspects of the design that depend on human factors --
will the seating be too high? Will the best area for lying down be too
large...? Will the rig be too heavy or too powerful to handle?
It's not an unreasonable way to come up with a new boat, just a rather
complicated one, which probably involves redesigning the whole structure
and rig. Just doubling the scantlings won't do it, and at that size
educated guesswork would be expensive.
I'd recommend Principles of Yacht Design
(http://www.amazon.com/exec/obidos/ASIN/0070364923/qid=942174709/sr=1-5/102-3520397-6380810),
for an more in depth discussion.
Maybe PCB would comment on this for you... or accept your commission?
- Charles Buchwald
David Ryan wrote:
surface area squared. Displacement (and therefore material requirements)
may be cubed. Forces on the rig and hull appendages will increase
geometrically, too. Will standard lumber sizes still work? Hardware?
What about those aspects of the design that depend on human factors --
will the seating be too high? Will the best area for lying down be too
large...? Will the rig be too heavy or too powerful to handle?
It's not an unreasonable way to come up with a new boat, just a rather
complicated one, which probably involves redesigning the whole structure
and rig. Just doubling the scantlings won't do it, and at that size
educated guesswork would be expensive.
I'd recommend Principles of Yacht Design
(http://www.amazon.com/exec/obidos/ASIN/0070364923/qid=942174709/sr=1-5/102-3520397-6380810),
for an more in depth discussion.
Maybe PCB would comment on this for you... or accept your commission?
- Charles Buchwald
David Ryan wrote:
> The particularly dangerous combination is "Boats with an Open Mind"
> and "The Sharpie Book." Between the two of these, dreams of doubling
> the scooner have been reignited!...<snip>
Fellow Bolger Boat Builders --
A trip to Amazon.com for one thin volume resulted in the purchase of
about 5 sailing books and transfer of about $100.00 from my account.
However, the ultimate cost may be much higher.
The particularly dangerous combination is "Boats with an Open Mind"
and "The Sharpie Book." Between the two of these, dreams of doubling
the scooner have been reignited!
Now before you call me crazy (again,) consider the following:
The Wyoming hull is not that much different from the scooner in it's
construction, is over 50 feet long, and goes real, real fast (lots of
stress.)
In a "Doubled Scooner" the largest sail would be about 450 ft.sq. A
quick tour of "Boats with an Open Mind" will show you several
unstayed gaff-rigged sails in that neighborhood of area, (some
mounted on sharpies too!) Assuming we're going to lower the overall
sail area on the Doubled Scooner, I think we've got a road map for
masts that won't break, or rip out of the hull.
In "The Sharpie Book" we're given strong testimony as to the
performance and seaworthiness of sharpies in this size range. Again,
construction techniques are not that different from the Light
Scooner, or any other "Instant Boat."
I am (of course,) considering a couple of modifications to the design:
A Rosalynn style vee on the bottom. This might make her ride a little
smoother and would add buoyancy.
This buoyancy would be counteracted by a lead shoe and/or weighted
daggerboard or centerboard.
Considering the "sporty" handling described by GHC and others, I am
inclined to think the sail rig should be scaled down. But perhaps
more reefing options is an even better idea.
Your's in boat building,
David Ryan
Minister of Information and Culture
Crumbling Empire Productions
(212) 247-0296
A trip to Amazon.com for one thin volume resulted in the purchase of
about 5 sailing books and transfer of about $100.00 from my account.
However, the ultimate cost may be much higher.
The particularly dangerous combination is "Boats with an Open Mind"
and "The Sharpie Book." Between the two of these, dreams of doubling
the scooner have been reignited!
Now before you call me crazy (again,) consider the following:
The Wyoming hull is not that much different from the scooner in it's
construction, is over 50 feet long, and goes real, real fast (lots of
stress.)
In a "Doubled Scooner" the largest sail would be about 450 ft.sq. A
quick tour of "Boats with an Open Mind" will show you several
unstayed gaff-rigged sails in that neighborhood of area, (some
mounted on sharpies too!) Assuming we're going to lower the overall
sail area on the Doubled Scooner, I think we've got a road map for
masts that won't break, or rip out of the hull.
In "The Sharpie Book" we're given strong testimony as to the
performance and seaworthiness of sharpies in this size range. Again,
construction techniques are not that different from the Light
Scooner, or any other "Instant Boat."
I am (of course,) considering a couple of modifications to the design:
A Rosalynn style vee on the bottom. This might make her ride a little
smoother and would add buoyancy.
This buoyancy would be counteracted by a lead shoe and/or weighted
daggerboard or centerboard.
Considering the "sporty" handling described by GHC and others, I am
inclined to think the sail rig should be scaled down. But perhaps
more reefing options is an even better idea.
Your's in boat building,
David Ryan
Minister of Information and Culture
Crumbling Empire Productions
(212) 247-0296