RE: displacement vs. dry weight?
Thanx Peter and Nels for the weighty insights. That's kinda what I thought. It's just that the occasional comment has confused me. Someone once remarked that a kayak and paddler displace 500 lbs. of water. My kayak weighs 38 lbs. and I weigh in at approx. 200 lbs. Even with my pfd and paddle that works out to more than 2:1. So I just wasn't sure.
Sadly I have no designs on Tomboy, assuming Chuck was looking for a buyer. In my usual salutations from the shores of Fundy I guess I've not referred to them as the "impoverished shores of Fundy" or the "economically depressed shores of Fundy", which would at least accurately describe my part of that rocky region. No, the JC I'm interested in was rather brutally damaged in a recent hurricane. She may be beyond rescue, but I plan to check her out tomorrow. My wife will accompany me on the inspection armed with a stun gun, so likely nothing will come of it. I'll keep you posted.
jeb, needing to "get a life" on the unforgiving shores of Fundy
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Sadly I have no designs on Tomboy, assuming Chuck was looking for a buyer. In my usual salutations from the shores of Fundy I guess I've not referred to them as the "impoverished shores of Fundy" or the "economically depressed shores of Fundy", which would at least accurately describe my part of that rocky region. No, the JC I'm interested in was rather brutally damaged in a recent hurricane. She may be beyond rescue, but I plan to check her out tomorrow. My wife will accompany me on the inspection armed with a stun gun, so likely nothing will come of it. I'll keep you posted.
jeb, needing to "get a life" on the unforgiving shores of Fundy
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Hi Peter,
Seems he is talking about a Jesse Cooper and not a Martha Jane.
Would the weight quoted not be the the total weight that would bring
her down to her lines? That is - loaded to capacity. Or am I way off
track hear?
I don't have any figures but I bet Chuck Merrell would since he has
built a Jesse Cooper.
http://boatdesign.com/tomboy/index.htm
I think it has 1000 lb internal ballest and a really thick bottom -
like another 1000 lb of plywood.
I expect it could be hauled on a full sized car hauler - on some sort
of cradle - like I hauled Lestat.
I wonder if Jeb is planning on buying Tomboy?;-)
Cheers, Nels
Seems he is talking about a Jesse Cooper and not a Martha Jane.
Would the weight quoted not be the the total weight that would bring
her down to her lines? That is - loaded to capacity. Or am I way off
track hear?
I don't have any figures but I bet Chuck Merrell would since he has
built a Jesse Cooper.
http://boatdesign.com/tomboy/index.htm
I think it has 1000 lb internal ballest and a really thick bottom -
like another 1000 lb of plywood.
I expect it could be hauled on a full sized car hauler - on some sort
of cradle - like I hauled Lestat.
I wonder if Jeb is planning on buying Tomboy?;-)
Cheers, Nels
--- Inbolger@yahoogroups.com, "pvanderwaart" <pvanderw@o...> wrote:
> > a formula for converting displacement weight to gross or trailer
> weight?
>
> The simplest answer is that pounds are pounds, and no adjustment is
> necessary. However....
>
> a formula for converting displacement weight to gross or trailerweight?
The simplest answer is that pounds are pounds, and no adjustment is
necessary. However....
Numbers representing boat weight can mean either of a couple of
different things. For factory built boats, the number bruited about
by the salesman is often the smallest number that he can justify,
since people think that light is good. For a power boat, this might
even be the weight of the empty hull minus motors. Or, in might
include normal equipment. For a sailboat, it should certainly include
spars, sails, inboard, etc. We might call this "brochure weight."
"Displacement" should be reserved for the number that the designer
uses to determine how the boat will float, and how strong to make it.
In most cases, this will bit 10% to 20% more than a reasonable
brochure weight. Of couse, displacement would include water ballast,
while trailer weight would not.
So it depends where you got the number for the Martha Jane. If it
came off the Bolger plan, then the boat would probably weight quite a
bit less on the trailer, especially if it has the water ballast
tanks. I would be pretty surprised, myself, if the weight of an
unballasted 22' plywood boat was much more than a ton and half. If it
was not so high-sided with a fancy interior, I would say a ton.
Peter
Can someone give me a formula for converting displacement weight to gross or trailer weight? Especially for a sharpie hull? For example, what would the 6150 lbs. displacement weight of Jessie Cooper = on giant bathroom scales? Please don't ask why I want to know. Yet. Thanx.
jeb, entertaining dangerous thoughts on the taunting shores of Fundy
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jeb, entertaining dangerous thoughts on the taunting shores of Fundy
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