Coosa board?

Looks interesting. I like the idea of no rot and lighter weight, but $296 for a 1/2x4x8 sheet is a little steep. What part of your boats were you planning on using it for?
 
Looks interesting. I like the idea of no rot and lighter weight, but $296 for a 1/2x4x8 sheet is a little steep. What part of your boats were you planning on using it for?
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THe only place we will use it is where it will provide the best bang for the buck. Transoms. Price when compared to using Marine ply is very comparable considering the measures required to seal and protect wood is concerned. Labor is costly and to protect wood with epoxy laminates is expensive. So the trade off is a little more money for a product that is never gonna rot, has strong holding power for screws etc.

We have never used this product, that is why we are asking to see if anyone here has or does. Sounds like a great product that makes sense.
 
Looks like it would be great for that. Seems like you are doing a great job in providing quality and reliability to an already great line of boats. I also really like how you are getting feedback and advice from other hunters. You are really creating the ultimate duck boat haha. Kudos to you my friend.

Also would love to see more pics of your operation.
 
Looks like it would be great for that. Seems like you are doing a great job in providing quality and reliability to an already great line of boats. I also really like how you are getting feedback and advice from other hunters. You are really creating the ultimate duck boat haha. Kudos to you my friend.

Also would love to see more pics of your operation.
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Thank you. We are new to big boat building ourselves. luckily for me I have a great friend who has worked for a multi million dollar boat company for a very long time and is helping us with the new TDB boats. One thing we wont do is build a product and start selling them and then start fixing the problems that arrise. While I am certain there can always be something to fix or modify. We believe The Duck Boats history and design has been proven already and now were just gonna tweak it so to speak with minor modifications in the construction to make them even better we believe. like the classc being rated for a 25hp hopefully. Simple little things like that.

We will continue to post pics and such of the progress. Nothing fancy here. just a 30x40 concrete brick building we build them in. But that allows us to keep overhead down and in the end the price.
 
Tony, the coosa board is just the ticket for transoms and anywhere you need high crush strength as in thru bolting cleats or other hardware. It is not what you would use for panel stiffening such as in decks or hull bottoms, it is just too heavy. I recently mounted a new mud motor on my hunt boat, when I drilled the transom , to thru bolt the motor, I was reminded of the high density coosa board in the transom. My 20 ft all glass garvey, [except for the transom which is starting to swell, where we thru bolted the motor] reminds me of how good that coosa board is for its intended purpose. Ask any of the local resinoids around here, how many plywood transoms they have dug out of glass boats over the years, and replaced with new plywood or high density foam. i am sure many have lost count. Rich
 
Coosa comes in many differant densities that can be perfect for walls, decks, hull coring etc... I was in the business for a long time and we were making boats with a competitor to Coosa. We used it everywhere, decks, hulls, transoms, interior walls, etc... While we used it for some structure, the primary intent was to quiet the boat. I'm talking the big boats, no small runabouts. We built Sea Rays, Cruisers, Carvers, Albemarle, etc... out of this material. Average dB reduction was 16 dB strategically using this product. I remember being down at Sea Ray in Merrit Island and having the top dogs come out to the 45'er we built. They were sitting in the cabin and told us to turn the boat on as they wanted to see how quiet and vibration free the boat was. When we told them the boat was running, they had to check for themselves. We also reduced the weight of some of the boats we built.

At one time I was going to build a duckboat out of this material using the low density version of the product. My calculations put the weight at around half the weight using an all wood construction.

Main problem I see, and that was mentioned, this stuff is not cheap. Since I was getting it for free, it was even going to cost less than wood ad epoxy.

Mark W
 
i put a new floor in my 23 foot center console with coosa board. not the cheapest way to go but definitely lighter an
d stronger. 3 years later it is still perfect
 
Tony
You should make every effort to correct any known problems and try to make sure any down the road fixes can be eliminated.
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Dennis, that is exactly what we are doing. The 2 major problems I hear are the Skid issue and the HP rating on the boat itself. There are other issues like the blind angles but thats later. Many guys are happy with the original design as well and it appears those not are those trying to put more than 2 people and a dog in the boat. But that too will be addressed.

While I am still up in the air over the wood composite debate we will be going with a composite transom and will be the best product available at what ever cost that is. Composites are changing daily and many havent had near the test of time as wood yet but things are promising so we will go all composites.
 
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Well, here goes the Rich/ Mark W foam core dispute again. Coosa or Bluewater foam core comes in three different densities Nautical24 at 24 lbs. per cu.ft. 20 at 20 and 15 naturally at 15 lbs per cu ft. The most commonly used core materials used in the boat building industry today are Divinycell and Core Cell. The density per cu. ft of Divinycell h-60 which is probably the most widely used of their structural cores for high performance hulls and decks is 4 lbs. per cu. ft. Core cell which is technically a little higher up on the evoloutionary core scale, weighs 5 lbs. per cu. ft. this is their A 500 grade. The core cell A 500 is primarily what we used in the construction of our 86 ft triple engine 7200 hp. 47 knot sportfish "Double Down". The idea of a cored structure is to create a rigid, stiff, lightweight panel, not to see how heavy we can make it. Some of the old school materials I grew up with and used, are woods like Cypress at 30.09 lbs per cu.ft. Western Red cedar at 21.48 lbs per cu. ft. White cedar at 21.98 lbs. per cu.ft. and Douglas fir at 31.96 lbs. per cu. ft not too different than the coosa. Believe me guys I know what I am talking about. No boat builder in his right mind would use those heavy core materials, when there are better performing cores at one third to one fifth the weight and much better properties. By the way, isnt Sea Ray out of business? Rich
 
Rich

Help me out here.

I know you build foam core (can't remember the brand) boats. Your method is basically the foam core panels are cut, and then you use decking screws and bondo to hold the parts in place and fair all the joints. Next you use layers of fiberglass and resin on both the interior and exterior and this is where the boats gains it's rigidity and strength. My understanding is the foam core is not structural, rather is is a form for the inner and outer lay-ups. The thicker the foam core the stronger the hull due to expansion/contraction properties of the structure's fiberglass layup. Also, they weight of your boats is from the fiberglass layups and not the foam core. Do I have this correct?

Now with stitch and glue the panels do offer much of the strength of the hull, as opposed to the fiberglass skins in your boats taking the load. So my question is why couldn't Coosa panels be used in place of plywood in a stitch and glue construction? Do they have the strength of plywood? Do the bond well with epoxy so the taped joints would be sufficient as are in plywood construction? If the Coosa panel is strong and wiegh less than plywood and bonds to epoxy as does plywood it seems lile they could be a substitute. Can you tell me if this is true or if I am failing to cxonsider something. Obviously my expereince is with marine plywood but the Coosa panels do interest me as a waterproof alternative if the boat can essentially be built in a stitch and glue fassion.

Youe inputs are appreciated.
 
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Rich,

Thanks for your input, this is a facinating subject and one most of us know little about.

Question: Can you relate the structural properties of your 4 and 5 lb/cuft. panels to the plywood that we are used to using? For example, how do these panels stand up in impact tests, elongation, tensil strength, etc.? I would think that if they are at the very least equal to plywood we could do a direct replacement without reengineering our hull configurations.
 
Rich,

Thanks for your input, this is a facinating subject and one most of us know little about.

Question: Can you relate the structural properties of your 4 and 5 lb/cuft. panels to the plywood that we are used to using? For example, how do these panels stand up in impact tests, elongation, tensil strength, etc.? I would think that if they are at the very least equal to plywood we could do a direct replacement without reengineering our hull configurations.
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Pete, Im not Rich and don't want to take away from his response. So please Rich respond as it sounds as your knowledge is much greater than mine on the subject.

here goes nothing.

Composite core has a weakness and that is Impact resistance. When it is impacted it distorted, creases or just plan breaks in to pieces. The strength comes from the laminate over the core material in the lighter thinner materials. This is my findings from many hrs of research on the products.

For example we make all our Layout boat stringers with 1/4 divinecell and laminate a layer of 1.5oz mat on both sizes and thats it. If we were to add a 6oz cloth over the laminate I bet it would be much stronger than 1/4 plywood without a doubt and probably still lighter in weight

There are many guys building complete boats using coring materials only. NO MOLDS. they simply make a jig like one would for a wood boat and are covering it with core material then glassing the exterior then removing from the jig and doing the interior. Composite core materials are amazing and can be used for virtually anything and the wood vs composite debate will continue as many boats are still built using wood as well as composites.
 
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Thanks Tony, Impact resistance was the one thing that had me wondering. I have some experience with polymers but not in a direct comparison with wood. Sounds like a great product as long as you understand it's limitations - like anything else.
 
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Here is core cell A 500 in action from the embrionic beginning to the running finished product . This boat weighed in at 167 000 lbs. mid load, it is not unusual in its construction, it is prettymuch the industry standard for one off foam and glass construction. If we used the lightest of the coosa cores the core weight would have tripled thus adding approximately 20,000 lbs to the hull alone. This is not a new venture for me, I have been doing this for 32 years. Check our website. www.tributeboats.com. Rich
 
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Here is core cell A 500 in action from the embrionic beginning to the running finished product . This boat weighed in at 167 000 lbs. mid load, it is not unusual in its construction, it is prettymuch the industry standard for one off foam and glass construction. If we used the lightest of the coosa cores the core weight would have tripled thus adding approximately 20,000 lbs to the hull alone. This is not a new venture for me, I have been doing this for 32 years. Check our website. www.tributeboats.com. Rich
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Holly smokes now thats a boat. Rich you wouldnt by chance have a few scraps of bluewater laying around you would sell would ya? Look at those piles of core. Love it.
 
Chasing cripples is he fun part, its spray canning the camo on each fall thats a lot of work. Tony, I have a 2 inch wide by 24 long by 3/4 strip and a big slab of 2 inck thick coosa laying on my rack. I could cut you a chunk of the 2 inch thick stuff and cut the 24 long one in half and send you some. PM me your address. Rich
 
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