Coosa board?

I have always wanted to pony up the funds for a core cell sneak boat. Since 75% or more of the weight of the core material is missing from the build, adding back in additional glass and epoxy will still result in a lighter boat. One day it will happen.

My one experiment with foam core was to follow the craze back in 2005 and build a blue board insulation foam boat. That build is on here some where still. It was interesting project, and a very useful boat, but the long term results were poor. Easily damaged and surpisingly hard to repair once damaged.

A child can poke a finger through insulation foam board. It has no compressive strength. It think it is rated at 5psi. The damage from impacts caused delamination. Actually the air in the foam cells expanding and contracting caused delamination before any impacts occured. It proved to me that if I want to build a light and cheap boat plywood is the only core material to use. If I wanted to build a lighter hull and money was not an issue then core cell foam would be the stuff I would use.

Today for sneak boats that would be impact prone I would look at a hull bottom with honey comb plasti-core. It is working well for drift boats in the Rockies as long as you know what materials to use and how to build with it. It is heavier than core cell, but not nearly as heavy as plywood.

Living in the ass end of North America makes the logistics for materials a real pain so I hold off on these plans until I can work with a local whole sale vendor to not rob me blind on shipping and material costs.
 
I have always wanted to pony up the funds for a core cell sneak boat. Since 75% or more of the weight of the core material is missing from the build, adding back in additional glass and epoxy will still result in a lighter boat. One day it will happen.

My one experiment with foam core was to follow the craze back in 2005 and build a blue board insulation foam boat. That build is on here some where still. It was interesting project, and a very useful boat, but the long term results were poor. Easily damaged and surpisingly hard to repair once damaged.

A child can poke a finger through insulation foam board. It has no compressive strength. It think it is rated at 5psi. The damage from impacts caused delamination. Actually the air in the foam cells expanding and contracting caused delamination before any impacts occured. It proved to me that if I want to build a light and cheap boat plywood is the only core material to use. If I wanted to build a lighter hull and money was not an issue then core cell foam would be the stuff I would use.

Today for sneak boats that would be impact prone I would look at a hull bottom with honey comb plasti-core. It is working well for drift boats in the Rockies as long as you know what materials to use and how to build with it. It is heavier than core cell, but not nearly as heavy as plywood.

Living in the ass end of North America makes the logistics for materials a real pain so I hold off on these plans until I can work with a local whole sale vendor to not rob me blind on shipping and material costs.
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Ray shop around you can buy some decent stuff at great prices. One place to look is Noahs marine, They seem to always have corecell cutoffs at great prices.

http://www.noahsmarine.com/items.asp?Cc=COREC%2DSECONDS
 
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coldduck.jpg

Here are the two core materials at work, only on a lesser scale, my scale. I might build these big war wagons for wealthy, powerful men, but I am definitely not one of them! My duck boat probably makes me happier than these big jobs make their owners. This boat weighed 175 lbs. dry, unrigged. Is extremely rigid and tough as nails. Rich
 
Rich wrote: 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? "

He has his experience, I have mine. I work for a fairly large corporation who helped boat builders build MANY boats using the fiberglass reinforced urethane foam composite materials. Many boats. Some of the very people Rich competes against with the boats he builds. Just cause Rich doesn't do it this way does not mean that others don't. Some are more educated, progressive, and I guess more up to date.

I sold the material for many years to boat builders to use as a coring material and structural materials. I ask you Rich, you ever go to any of the boat building shows? Aren't these material supplier exhibing at the show? Why would they be at these shows spending a bunch of bucks to exhibit if they did not have a business?

I'm tired of having "Mr know it all" telling me people don't use these materials for these types of applications when I know 100% that they do. I've been there, I've helped build the boats, these boats are out on the water today.

When did Sea Ray go out of business? http://www.searay.com/ What are you smoking Rich? Better check your facts - oh wait, you know everything so I must be wrong again.

They just won a 2012 innovation award with their new Quiet Ride system. Guess who introduced them to the Quiet Ride system? Wonder who brought in the sound engineers (same company who makes the US sub fleets quiet) using a proprietary 16 channel accellerometer to measure exactly where these vibrate and then determined how to isolate these vibrations using constrained layer damping materials that utilize the uerethan boards. How about bringing in PYI motor mounts and shaft couplers to further reduce noise. Yep, that was me Rich - the guy who knows nothnig about what he is talking about.

http://www.searay.com/page.aspx/pageid/147155/page.aspx

Maybe Rich should read the original posts questions - "Has anyone ever used this material". Unless you know what I've specifically done Rich you best keep quiet.

Mark W
 
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Mark, I know the east coast is in kind of a vacuum as far as boat building technology is concerned, especially south florida! You had me thinking on our last go around, so I consulted two of the most respected composite engineers in the industry. They thougt my question was quite amusing and answered emphatically NO! these cores [coosa/bluewater] are not the right material for hulls, decks, superstructures etc. Mark I know where you work, I think you should stick to making sticky, gooey, scratchy stuff and let the real boat builders do their jobs. Rich
 
Went to the Coosa site and low and behold, right on their home page, and you can read this for yourself, they specifically state that their material can be used for coring and other structural and non structural applications. I would think the manufacturer of the product would know what their product can be used for. Believe it or not, some of these urethane boards are being used to build aircraft where weight really does matter.

http://www.coosacomposites.com/

"Coosa Composites manufactures structural panels made of high-density, polyurethane foam reinforced with layers of fiberglass. The no-rot and light-weight advantages of foam combined with the structural properties of fiberglass make Coosa panels an excellent replacement material for wood and other traditional core materials. Coosa panels are used throughout the marine, industrial and transportation industries in structural and non-structural applications."

Eric - while what you propose would work, this material is unlike plywood in that it will not bend. I think folks get confused when they think of foam boards - this is not like a home insulation foam board or like a divinycell product. It is very tough and rigid. You would not be able to put your finger through this board nor "dent" it when you do push against it with your finger.

It is possible to put in scarf lines in the board so it can bend. We did this and while it works to put some "bend" in the board, it wasn't a real good solution. We also took some board, cut it into 2" X 2" size pieces and laminated a fiberglass scrim to the back. Sort of like how small 1" X 1" tile comes with a bunch of them stuck together to form a 1' X 1' panel. We were then able to use this type of construction to put this product where some bend was needed. Once again, not a great solution but it did work.

Where this product would be great in the type of boat you would build with the stich and glue method would be for flooring and for bulkheads. It would be stiff enough and depending upon the density of the board you chose, up to 62% lighter than comparable plywood. Also great for your transom.
 
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Ray shop around you can buy some decent stuff at great prices. One place to look is Noahs marine, They seem to always have corecell cutoffs at great prices.

http://www.noahsmarine.com/...p?Cc=COREC%2DSECONDS
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I know I can buy it all over the place, but the shipping of it to Alaska makes it cost prohibitive. Most retailers will only ship UPS, which means to get it here I have to pay second day air rates for a week long delivery time. Second day air on a box that meets the UPS ground rate size restrictions is over $50. By the time I have enough scrap cut offs to build a boat, I will have paid more in shipping costs than material costs.

There are retailers in Seattle that cell core materials in shippable sizes. However, I have to talk them into driving it to a barge service like Northland Marine and shipping it that way rather than through UPS. It worked when I built my BBIII when they discontinued carrying WEST epoxy, but these days they don't want to mess with small orders. I don't want to buy a flat of core cell for a sneak boat. The local specialty wood supplier might be interested in helping me out, but I have yet to make the time to talk to him.
 
Ray,

Sounds like it's time to develop your aluminum welding skills. Find a scrapped out larger aluminum boat and salvage the aluminum. Better for handling abuse than about any other material, and works well for "stitch & glue" designs.

View attachment Rscottsboat2.JPG

Just saw your post on "boat building Questions" that your running a Nissan 25. I just (this summer) upgraded mine to the 30 HP config and am pleased with the results. Only difference physically is the swap out of a restricter plate between the carb and head. Replace with gasket for the 30 hp about $5 (before shipping to AK). Timing gets changed from 20 degrees tdc to 25 degrees at WOT and verify that the carb butterfly valve is fully open at WOT. Takes almost no time to get a 20% power increase.

Scott
 
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Sounds like it's time to develop your aluminum welding skills.
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That is on my to do list once child support is completed in a few more years. However, I need a shop that won't burn to the ground in an instant if some slag gets away from me. Having a wood shop and welding shop in the same square feet is a little too dicey.
 
Ray,

Sounds like it's time to develop your aluminum welding skills. Find a scrapped out larger aluminum boat and salvage the aluminum. Better for handling abuse than about any other material, and works well for "stitch & glue" designs.



Just saw your post on "boat building Questions" that your running a Nissan 25. I just (this summer) upgraded mine to the 30 HP config and am pleased with the results. Only difference physically is the swap out of a restricter plate between the carb and head. Replace with gasket for the 30 hp about $5 (before shipping to AK). Timing gets changed from 20 degrees tdc to 25 degrees at WOT and verify that the carb butterfly valve is fully open at WOT. Takes almost no time to get a 20% power increase.

Scott
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That looks alot easier than fiberglass, But I cannot weld a lick. A great looking project indeed.
 
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