From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?

Frogwatch wrote:
From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?


Build it out of plate aluminum with a deck and sealed flotation chambers
underneath. Drive slowly down the side of the road and gather up empty
aluminum sodapop cans, roll them out and weld them together.

On Jun 29, 2:34*pm, Gene wrote:
On Mon, 29 Jun 2009 11:19:01 -0700 (PDT), Frogwatch

wrote:
From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. *So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. *More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?

By definition: flats boat. *Stay out of the waves....
--

Forté Agent 5.00 Build 1171

"Twenty years from now you will be more disappointed by
the things you didn't do than by the ones you did do.
So, throw off the bowlines. Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." * - Unknown

Grady-White Gulfstream, out of Oak Island, NC.

Homepagehttp://pamandgene.tranquilrefuge.net/boating/the_boat/my_boat.htm

Tolman reccomends a 60 hp engine for my 20' Tolman Standard because it
is so light. I went with a 90 hp 2 stroke but its weight plus the 9.9
kicker was enough that I had to place my batteries forward and run 00
gage battery cable (expensive) and I have to be careful to have my
passengers sit forward to balance here well.
So, what if I went with a 125 hp 2 stroke and placed my batteries even
further forward AND incorporated tanks that could be filled with
seawater to give her enough momentum to get through waves (also assume
more deadrise). She could be lightweight for normal conditions but
then heavy enough (by filling the tanks) for wavy conditions.

On Mon, 29 Jun 2009 11:19:01 -0700 (PDT), Frogwatch
wrote:

From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?

I'm not an engineer, but I'll guess a bit.
Yeah, weigh affects stability, and there's no way around it.
But, hull design can help as far as wave action.
The cat-type hulls on that Intruder seem to cut water and hold
direction to some extent. Didn't seem to pound badly, but I think you
have to be there doing a kidney-check to really tell.
Seems to me the major problem with a lighter hull will be the
"cork-like" aspect of bobbing up and down.
Anyway, I was thinking inshore boats more than ocean-going.
Fishing and other recreation boats.
The Intruder videos said they were in 8' seas.
Don't know if that was true.
But again, I'm not looking for a heavy weather boat.
I'll bet 90% of recreational boating miles is in good weather,
and 99.9% is in decent weather.
Can't make a perfect boat.
I was thinking along the lines of styrofoam-like weight.
Hardened on the outside with something light, and maybe
internally stiffened with something light.
Could even be made cheaply enough to throw away the hull
after not too many years.
Prettifying it and gussying it up will happen pretty quick for some,
but the Carolina Skiff has found a market for bare-bones, and an even
lighter boat will do it one step further.

--Vic

--Vic

On Jun 29, 2:59*pm, Gene wrote:
On Mon, 29 Jun 2009 11:41:18 -0700 (PDT), Frogwatch



wrote:
On Jun 29, 2:34*pm, Gene wrote:
On Mon, 29 Jun 2009 11:19:01 -0700 (PDT), Frogwatch

wrote:
From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. *So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. *More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?

By definition: flats boat. *Stay out of the waves....
--

Forté Agent 5.00 Build 1171

"Twenty years from now you will be more disappointed by
the things you didn't do than by the ones you did do.
So, throw off the bowlines. Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." * - Unknown

Grady-White Gulfstream, out of Oak Island, NC.

Homepagehttp://pamandgene.tranquilrefuge.net/boating/the_boat/my_boat.htm

Tolman reccomends a 60 hp engine for my 20' Tolman Standard because it
is so light. *I went with a 90 hp 2 stroke but its weight plus the 9.9
kicker was enough that I had to place my batteries forward and run 00
gage battery cable (expensive) and I have to be careful to have my
passengers sit forward to balance here well.
So, what if I went with a 125 hp 2 stroke and placed my batteries even
further forward AND incorporated tanks that could be filled with
seawater to give her enough momentum to get through waves (also assume
more deadrise). *She could be lightweight for normal conditions but
then heavy enough (by filling the tanks) for wavy conditions.

I would guess that you would have taken an excellent design, modified
it in a manner that made it less seaworthy, and overpowered and then
considered an even worse alternative.

Doesn't something ring a safety/engineering/usability bell when you
consider that you are more than doubling the recommended HP rating?

However, I'm not familiar with Tolman and I can only guess.....

Seaworthiness can't be distilled to weight per unit volume.....
--

Forté Agent 5.00 Build 1171

"Twenty years from now you will be more disappointed by
the things you didn't do than by the ones you did do.
So, throw off the bowlines. Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." * - Unknown

Grady-White Gulfstream, out of Oak Island, NC.

Homepagehttp://pamandgene.tranquilrefuge.net/boating/the_boat/my_boat.htm

Gene, this is purely hypothetical.
I would not make such a radical change without consulting the
designer. I e-mailed him when I went to a heavier engine for my 20'
Tolman and said to simply balance it.

Frogwatch wrote:
On Jun 29, 2:34 pm, Gene wrote:
On Mon, 29 Jun 2009 11:19:01 -0700 (PDT), Frogwatch

wrote:
From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?
By definition: flats boat. Stay out of the waves....
--

Forté Agent 5.00 Build 1171

"Twenty years from now you will be more disappointed by
the things you didn't do than by the ones you did do.
So, throw off the bowlines. Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." - Unknown

Grady-White Gulfstream, out of Oak Island, NC.

Homepagehttp://pamandgene.tranquilrefuge.net/boating/the_boat/my_boat.htm

Tolman reccomends a 60 hp engine for my 20' Tolman Standard because it
is so light. I went with a 90 hp 2 stroke but its weight plus the 9.9
kicker was enough that I had to place my batteries forward and run 00
gage battery cable (expensive) and I have to be careful to have my
passengers sit forward to balance here well.
So, what if I went with a 125 hp 2 stroke and placed my batteries even
further forward AND incorporated tanks that could be filled with
seawater to give her enough momentum to get through waves (also assume
more deadrise). She could be lightweight for normal conditions but
then heavy enough (by filling the tanks) for wavy conditions.

Don't forget the waterwings.

Gene wrote:
On Mon, 29 Jun 2009 11:41:18 -0700 (PDT), Frogwatch
wrote:

On Jun 29, 2:34 pm, Gene wrote:
On Mon, 29 Jun 2009 11:19:01 -0700 (PDT), Frogwatch

wrote:
From what I can determine, once a boat is on plane, it is primarily
the weight that determines fuel efficiency so a lighter weight boat
should give much better fuel economy.
BUT, as I have found with my Tolman which is very light for her size,
a lightweight boat is easily pushed around by a wave due to less
momentum. So, although you might consider a boat made from new
lightweight composites, would it be as seaworthy as a heavier one?
This is actually a practical consideration for me if I build a Tolman
Jumbo with slightly gretaer deadrise than the design. More deadrise
will make her pound less but will the lightweight make her less
seaworthy than similar heavier boats?
By definition: flats boat. Stay out of the waves....
--

Forté Agent 5.00 Build 1171

"Twenty years from now you will be more disappointed by
the things you didn't do than by the ones you did do.
So, throw off the bowlines. Sail away from the safe harbor.
Catch the trade winds in your sails.
Explore. Dream. Discover." - Unknown

Grady-White Gulfstream, out of Oak Island, NC.

Homepagehttp://pamandgene.tranquilrefuge.net/boating/the_boat/my_boat.htm
Tolman reccomends a 60 hp engine for my 20' Tolman Standard because it
is so light. I went with a 90 hp 2 stroke but its weight plus the 9.9
kicker was enough that I had to place my batteries forward and run 00
gage battery cable (expensive) and I have to be careful to have my
passengers sit forward to balance here well.
So, what if I went with a 125 hp 2 stroke and placed my batteries even
further forward AND incorporated tanks that could be filled with
seawater to give her enough momentum to get through waves (also assume
more deadrise). She could be lightweight for normal conditions but
then heavy enough (by filling the tanks) for wavy conditions.

I would guess that you would have taken an excellent design, modified
it in a manner that made it less seaworthy, and overpowered and then
considered an even worse alternative.

Doesn't something ring a safety/engineering/usability bell when you
consider that you are more than doubling the recommended HP rating?

However, I'm not familiar with Tolman and I can only guess.....

Seaworthiness can't be distilled to weight per unit volume.....


Hehehe. You are so much more polite than I am, Gene. To me, Froggy is a
boating disaster waiting to happen.

On Mon, 29 Jun 2009 13:50:56 -0500, Vic Smith
wrote:

But again, I'm not looking for a heavy weather boat.

There are those who carry a .22 handgun. As long as they don't use it
the lack of stopping power doesn't matter. Or does it?

On Mon, 29 Jun 2009 18:07:03 -0500, Richard Casady
wrote:

On Mon, 29 Jun 2009 13:50:56 -0500, Vic Smith
wrote:

But again, I'm not looking for a heavy weather boat.

There are those who carry a .22 handgun. As long as they don't use it
the lack of stopping power doesn't matter. Or does it?

Don't know. I could say,
"But being as this is a .44 Magnum, the most powerful handgun in the
world, and would blow your head clean off, you've got to ask yourself
one question: Do I feel lucky? Well, do ya, punk?"

Or I could say "What's your point, Vanessa?"

But let me just get your recommendation for a heavy weather flats
boat.

--Vic

On Mon, 29 Jun 2009 13:50:56 -0500, Vic Smith
wrote:

I was thinking along the lines of styrofoam-like weight.
Hardened on the outside with something light, and maybe
internally stiffened with something light.

Yes, like a SeaRay !

(I can talk like that since I own one)

It's important to remember that "ride quality" and "sea worthiness"
are only loosely related. You can in fact take a boat with a hard
ride and make it better by adding weight. At the same time however,
freeboard is lowered which makes it inherently less seaworthy, and
possibly less stable depending on where and how the weight was added.
Also, fuel consumption will increase and speed will decrease.

There's just no free lunch here.