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Old 14-05-2008, 10:57   #121
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The first two pages were great, then it got lost in water balancing mono's and how heavy is your cat suposed to be. I'm going back to read the first two pages again.
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Old 14-05-2008, 11:26   #122
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Quote:
Originally Posted by rickm505 View Post
infusion molding techniques?
Atlantics hulls use epoxy foam coreprimer are vacuum bag sealed and vacuum infusion molded, so there is no difference there in weight savings.

Are you now saying, the weight given as ready to sail is actually even 1,800 lbs less? ) It is only 11,000 lbs empty weight; with engines, tanks, and electrical installed?

Quote from your web site.
"Due to the extensive use of Carbon and Basalt Fibre, African Cats has been able to even decrease the weight of FASTCAT 455 ready to sail to 5800 kilo’s or 12.760 Lbs."
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Old 14-05-2008, 11:33   #123
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If we are going to critique websites, my two cents is, please, no Flash, and nothing moving except a boat underway. HTML only, no Java, etc.
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Old 14-05-2008, 12:56   #124
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Quote:
Originally Posted by ldrhawke View Post
Atlantics hulls use epoxy foam coreprimer are vacuum bag sealed and vacuum infusion molded, so there is no difference there in weight savings.

Are you now saying, the weight given as ready to sail is actually even 1,800 lbs less? ) It is only 11,000 lbs empty weight; with engines, tanks, and electrical installed?

Quote from your web site.
"Due to the extensive use of Carbon and Basalt Fibre, African Cats has been able to even decrease the weight of FASTCAT 455 ready to sail to 5800 kilo’s or 12.760 Lbs."
What I am trying to say is that maybe the Atlantic has taken filled tanks for both diesel and water into account while we calculate with empty tanks. The Fastcat launched yesterday has a weight of around 6000 kilo with airco 2 x 40 hp diesels, heater ,watermaker , solar panels , wind generator, Hard top bimini, Oven , 4 burner stove , microwave and all the goodies you can think of. when she is in the crane coming monday we will know the exact weight but I am sure it is probably less than the 6000 kilo

Greetings

Gideon
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Old 14-05-2008, 13:24   #125
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If you can get the yacht's designer to tell you exactly how much freeboard it has amidships when on its DWL, and its PPI (pounds per inch of immersion,) you can measure and find out how much it displaces without any problem.
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Old 14-05-2008, 13:41   #126
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Hallo David
Unfortunately Excell sheets cannot be loaded on the forum although I have asked repeatedly if that would be possible.
Regarding your questions the following
Tensile strenght of the mentioned materials and I leave Kevlar /Twaron out of this since this is not a fiber to be used for boat building , just for impact resistancy.
Tensile stenght Mpa Load capacity Relative price and e glass is 1
E Glass = 2500 Mpa 4.76 % 1.
S Glass = 4050 Mpa 5.0 % 6.
Carbon = 3000 Mpa 1.59 % 30.
Basalt = 4300 Mpa 2.8 % 5.

Basalt has other advantages over carbon not electric conductive, sound dampening while carbon is sound enhancing and non corrosive even in contact with salt water while all the other mentioned materials are corrosive in contact with salt water.
I have attached a picture of the launch of Africa Seawing last year with a small high aspect ratio keel.
You are right Our web site if a disaster , it is all my fault , I am the type of guy that like to develope and improve the product all the time and forgets about the web site , I have it high on my agenda to do something about it later this year. It has bothered me as much as you but developing new drive systems like Green Motion and developing 3 new catamarans at the same time plus the introduction of a new type of fiber and getting the CE approval for it .And then offcourse the renewed 455 making this cat lighter longer and higher while reducing weight is a continues task, We are also in the process to move into our new factory next week.
offcourse we are still working on making the New Rigid inflatable lighter in weight, we are now at 40 Lbs for the 11 ft model but the aim is 35 so there is some work to do.
You know the story we all only have one head and 2 hands. but again you are absolutely right. Our web site is nothing short of a disaster.

And David I like to be criticized only with critical people around you will I learn to improve
Greetings

Gideon
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Old 14-05-2008, 13:51   #127
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Quote:
Originally Posted by fastcat435 View Post
What I am trying to say is that maybe the Atlantic has taken filled tanks for both diesel and water into account while we calculate with empty tanks. The Fastcat launched yesterday has a weight of around 6000 kilo with airco 2 x 40 hp diesels, heater ,watermaker , solar panels , wind generator, Hard top bimini, Oven , 4 burner stove , microwave and all the goodies you can think of. when she is in the crane coming monday we will know the exact weight but I am sure it is probably less than the 6000 kilo

Greetings

Gideon
Even with the Atlantic 48 tanks topped off with 150 G of fuel and 150G of water, your boat is still stated to be nearly 7,000 lbs lighter than a similar size Atlantic....that's a bunch. It's almost a whole boat. Knowing how sensitive Chris White is about his Atlantic boat weights, I find it difficult to believe he would say any of his boats weighed more that they really did.

It appears someone is either highly conservative or someone over zealous in their weight specs and how they estimate. There should be a clear definition and method for all boat builders to use in publishing boat weights. From what I've read and seen, boat builders like to make catamarans look lighter than they really are in their brochures and specs.

Quote:
If you can get the yacht's designer to tell you exactly how much freeboard it has amidships when on its DWL, and its PPI (pounds per inch of immersion,) you can measure and find out how much it displaces without any problem.
Chris does that.....If you add 6,000 lbs of load you are setting 4" deeper in the water.
Quote:
ATLANTIC 48 CATAMARAN
Specifications
Length 48' 7"
Beam 26'3"
Draft 3'2" to 7'8"
Wing Clearance 36" at cruising displacement
Masthead from WL 70' (approx.)
Displacement 21,500 lbs
Pounds per inch immersion: 1,524
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Old 14-05-2008, 14:29   #128
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The Immersion rate of the FastCat 435 is 209 kilo per 10 mm or 1170 lbs per inch at DWL. The diffrence between Chris and me is , he designs and we actually build , I have yet to see the first Atlantic that was resin infused , not with Alwoplast and not with Bonger marine but maybe somewhere else ???
I do not compare our cat with a Atlantic or with A Gunboat for instance these are both fine cats but we are in a different leage as far as weight is concerned. I have yet to see the first boat builder that has a spread sheet with ever item and part of the boat on it with weights of each item, the only exception are racing boat builders
With each Fastcat every new infused part is put on to a scale for weight we even heat the foam for pre forming so the resin absorbtion of the foam is lower .
This so far is only done with Aircraft manufacturing as far as I know.
Weight is an obsession in our company and a staff member that comes up with a weight saving idea is rewarded .
Off course the fastCat is substantially smaller than the Atlantic , we are just 46 feet while the atlantic is almost 49 feet and the beam is also smaller , 24 ft 7 in so that explains the excessive weight difference.

Greetings
Gideon

p.s. we are still bringing the weight down further
the new interiors are build with nomex Kevlar honey comb for 125 kilo,s of weight saved and we have a few other tricks up our sleeve
The aim is less than 5000 kilo ready to sail
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Old 14-05-2008, 15:43   #129
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Quote:
Originally Posted by fastcat435 View Post
The Immersion rate of the FastCat 435 is 209 kilo per 10 mm or 1170 lbs per inch at DWL. The diffrence between Chris and me is , he designs and we actually build , I have yet to see the first Atlantic that was resin infused , not with Alwoplast and not with Bonger marine but maybe somewhere else ???
I do not compare our cat with a Atlantic or with A Gunboat for instance these are both fine cats but we are in a different leage as far as weight is concerned. I have yet to see the first boat builder that has a spread sheet with ever item and part of the boat on it with weights of each item, the only exception are racing boat builders
With each Fastcat every new infused part is put on to a scale for weight we even heat the foam for pre forming so the resin absorbtion of the foam is lower .
This so far is only done with Aircraft manufacturing as far as I know.
Weight is an obsession in our company and a staff member that comes up with a weight saving idea is rewarded .
Off course the fastCat is substantially smaller than the Atlantic , we are just 46 feet while the atlantic is almost 49 feet and the beam is also smaller , 24 ft 7 in so that explains the excessive weight difference.

Greetings
Gideon

p.s. we are still bringing the weight down further
the new interiors are build with nomex Kevlar honey comb for 125 kilo,s of weight saved and we have a few other tricks up our sleeve
The aim is less than 5000 kilo ready to sail

Now you have.......

Quote:
Alwoplast signed a third contract with another US client for a Chris White designed high performance Atlantic 57 sail catamaran, developed out of the very successful and proven Atlantic 55.
The A-57 is fast and rugged, designed to sail her owners anywhere in the world in comfort. A new negative hull mould has been made available and the vacuum bagged multiaxial glass/ carbon fiber/ epoxy/ foam cored construction has started.
Quote:
The Atlantic 55 is the most recent design in the innovative and award winning series of cruising catamarans from Chris White Designs. In full production in vacuum bagged glass/carbon fiber/epoxy. She is fast and rugged, designed to sail her owners anywhere in the world in comfort

Chris White has specialized in the design of cruising multihulls since 1979. His catamaran and trimaran designs blend comfort, safety and excellent performance. For over 20 years his designs have an exceptional record of cruising safety and owner satisfaction.


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Old 14-05-2008, 15:48   #130
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If we are going to critique websites, my two cents is, please, no Flash, and nothing moving except a boat underway. HTML only, no Java, etc.
BigCat,
Gawd you are so right...Java and Flash always make a website look amateurish. BTW, Gideon has none on his.

Gideon,
I am glad you were not offended by my website critique.
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Old 14-05-2008, 15:51   #131
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Sweet looking boat.

Is that a forward door?...uh, hatch.

I went to Chris's website. The Atlantic 57 had me drooling. Gag me with a spoon though, the helm is outside and forward! That leaves the helmsman lonely, wet and sunburned. ...easy remedy though with a Sawzall and duct tape.

Chris White Designs Atlantic 57
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Old 14-05-2008, 23:59   #132
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What I see on the picture is vacuum bagging not resin infusion at all You probably do not know the difference but I will tell you.
With vacuum bagging the already hand laid up parts are after the lamination job vacuum bagged to get excess resin out.
With Resin infusion all the laminate fibers and foam etc is put in the Mould dry and all is put under vacuum , in our case 24 hours to compact the laminate than we open epoxy lines and the epoxy is drawn in under vacuum .
Another difference I see is that we do a complete hull and deck in one shot while here the hull sides are first made separate and than glassed together and that takes a lot of extra tabbing and fairing , probably 100 kilo,s per hull.
If we where to build the Atlantic 48 we would get it in under 15000 LBS in our technique and make it even stronger.
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Old 15-05-2008, 00:17   #133
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Anorexic boats

Be careful you don't give your poor boats Anorexia / Bulimia! It's a slippery path!
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Old 15-05-2008, 02:24   #134
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Be careful you don't give your poor boats Anorexia / Bulimia! It's a slippery path!

Yer you are right BigCat, are we building our cruising boats too light for everyday use and abuse?
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Old 15-05-2008, 05:30   #135
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Lighter means less stress on the boat. Weight for the sake of weight is silly.
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