Big Catamaran, Big Drop 'Test',....WHAM !!

[beiland]

The following quote is taken from a piece of literature (manual) that was utilized by the NidaCore company as a sales pitch in support of their PP honeycomb core product.

A customer of the NidaCore Corp, in the Caribbean islands had a 65' commercial charter boat, cored entirely with NidaCore polypropylene honeycomb (less the hull bottom), including hull sides, deck and superstructure. It was scratched and water damaged on a coral reef during a major hurricane. The insurance copany agreed to write off the boat on condition that customer takes boat out of service and does not attempt to repair it. The charter boat operator agreed to dismantle the boat and discard of it.

Using one of the marina's cranes, they hoisted the 50,000 lb boat 50 feet in the air and dropped it onto a concrete parking lot, hoping that they would be able to collect the pieces and discard of them in the dumpster. To much of their astonishment the boat remained completely intact, with no visable structural damage. They repeated the procedure continuously for a couple of days to no avail. Finally to accomplish their mission they had no other alternative than to rent a chainsaw to cut the boat into pieces.


Although somewhat of an extreme example, it clearly indicates the superior nature of a 'resilient' cored-sandwich construction in boats. The increase in impact strength as compared to single-skin laminates is better demonstrated if one sees the core as a shock absorber that evenly supports the outside skin from impacts and protects the inside skin, while still having enough elasticity maintain the bond line between the core and the skins. Experience shows that although sandwich construction is not completely punture proof, it significantly increases skin penetrating puncture resistance.


The more brittle cross-linked PVC and SAN foams would simply crumble and shear under a sever impact whereas polypropylene honeycomb cored structures would be locally damaged, however the core structure would be intact, and cells, although elongated would still keep their structure and shape, ready to absorp or withstand more impacts and compressions.

There are no other specifics supplied,...such as name of vessel, charter organization, island location or marina where this was carried out, what hurricane, etc. And it may have occurred before wide spread info dissemination by the internet came into being?

Is there anyone with any more knowledge as to the details of this 'event' ??

[neilpride]

50000 pounds honeywhat and droped at 50 ft and remain intact my ass!! Hard to believe... really..

[dpddj]

Well, when you consider NidaCore is made from the same plastic milf bottles are made from, I'm not so sure I'd consider that a plus. Bounce and flex. I know some flex is good in hulls, but flexible flyer soft? Not for me. Cored hulls, yes, but poly hulls? PVC and SAN will not crumble. Urethane will though. It's amazing what marketing is presented to dupe people. Let's light that baby on fire and see what happens. Ever take a plastic dry cleaning bag, tie it in knots, hang it from the ceiling and light it?
Shaking my head.

[Sea Frog]

Originally Posted by dpddj

Well, when you consider NidaCore is made from the same plastic milf bottles are made from

I tried to google for a "milf bottle" and was shocked!!! What I am missing here?

[Dave]

Originally Posted by dpddj

Well, when you consider NidaCore is made from the same plastic milf bottles are made from, I'm not so sure I'd consider that a plus. Bounce and flex. I know some flex is good in hulls, but flexible flyer soft? Not for me. Cored hulls, yes, but poly hulls? PVC and SAN will not crumble. Urethane will though. It's amazing what marketing is presented to dupe people. Let's light that baby on fire and see what happens. Ever take a plastic dry cleaning bag, tie it in knots, hang it from the ceiling and light it?
Shaking my head.

Brief search shows H8PP core claims to be inflammable. Sounds like a great core material. Impressive list of applications.

Nida-Core Thermoplastic Honeycomb Core Structural Materials for the Marine Industry

Dave L38 #38

[beiland]

Have you visited this website?
Polycore Composites - Polycore Australia - Polycore Honeycomb

Polycore has achieved a world first with it's Polypropylene Honeycomb Core and Panels!
The PP8-S and PP8-H Core can be supplied with an advanced fire treatment, this has resulted in a plastic honeycomb core that will not ignite, without ignition there is no spread of flame, without fire there are no toxic fumes to worry about.

Have you visited these fire videos
http://www.polycore-australia.com.au...ant-Panels.php

[beiland]

BTW I posted this individual subject thread to seek out info on this particular 'incident' of dropping the big cat,...as there were a number of non-believers when I included it discussions over here:
http://www.cruisersforum.com/forums/...-22948-13.html

To tell the truth I was skeptical myself as it is not backed up with any supporting documentation.

However someone on another subject thread has suggested it was a charter cat that might have been built by Gold Coast (USVI) , possible damaged in that huge hurricane they had down there that passed right over St Croix. I have written Gold Coast Yachts and ask it they knew of this incident.

I'm trying to remember the date of that BIG hurricane that hit St Croix. I had only months before deliveried one of out Firefly trimarans to St Croix client. It was anchored just off the shore on a mooring. It was never heard of again after that storm.

[neilpride]

Look, is hard to believe that history, we drop few boats here in the Boatyard, boats with a huge bill to pay and owners missing somewhere else for years, the paperwork involved is a nightmare, most cranes here lift a max of 14 or 15 tons , more is posible but at your own risk , holding a huge cat at 20 ft in the air and droping to the ground dont make any sense at all, monohulls get their keels in the saloon after a the big Bang, and later is easy to chainsaw and discard, also note that most cranes,, lift this boats with a big and strong rope , some gasoline in the rope, fire and here we goo, just figurate the show,,, 50000 pounds is 20 something tons , no rope hold this weight, maybe a tug line , expensive to fire it up.. and all the risk involved for the crane operator and crews,,, its cheaper and safer to sank the whole thing in thousands ft of water and thats it,,,
my opinion,....

[dpddj]

Big fingers late at night. Interesting thought, though I suppose silicone would be more appropriate..

[aclmck]

Polycore has shut down and is no longer trading, so probably impossible to get now.

The core was expensive to use and many alternatives were available in never used this product but felt there was a place for it in the market, but to be honest when claims of dropping a 20 tonne boat several times from height are "claimed " in the documents most people would keep walking.When they were in business i asked for some specific details regarding the test documents they supplied but they were not forthcoming so you can read into it whatever you like,lazy,perhaps false, who knows but it didn't tick all the boxes then and doesn't now.

Something is also getting clouded by the fact Now this product is produced on Australia's GOLD Coast now the boat was supposed to be dropped in the usvi Gold Coast.

It will be easier to prove this happened by looking for a crane that could actually do such a job they are few and far between would be worth millions and cost 100's of thousands to even set up , all to demolish a boat that would take a chainsaw a few hours.

Why so much involvement in a failed company???? are you now the seller or producer of this product and using this forum to get it off the ground again.

In latter years the company turned to making panels for truck trailers and vans , so they should have been successful if the product worked as well as they claimed. i saw a truck that had smashed and the "panel wreckage" would not support the claims of the "dropped boat".

[colemj]

Originally Posted by aclmck

Something is also getting clouded by the fact Now this product is produced on Australia's GOLD Coast now the boat was supposed to be dropped in the usvi Gold Coast.

A bit of confusion there. Gold Coast is the name of a manufacturer of catamarans based in St. Croix VI. I don't think the poster was referring geographically to Australia's Gold Coast.

Mark

[aclmck]

Originally Posted by colemj

A bit of confusion there. Gold Coast is the name of a manufacturer of catamarans based in St. Croix VI. I don't think the poster was referring geographically to Australia's Gold Coast.

Mark

Sorry Mark , Yes it was in i think post 6 "polycore Australia" in blue highlighted writing.

some of this info was not put up on the other thread, and i'm curious why someone is so interested in a product that is now out of business (by their own admission)

[beiland]

I think perhaps you might be confused with some of these tradenames etc, as I was when trying to sort thru the core materials of DuFlex panels

Originally Posted by aclmck

Polycore has shut down and is no longer trading, so probably impossible to get now.
Where did you determine this, I have seen no such notice? NidaCore in the USA was bought out by 3M. Is that possible what you speak of?

The core was expensive to use and many alternatives were available in never used this product but felt there was a place for it in the market, but to be honest when claims of dropping a 20 tonne boat several times from height are "claimed " in the documents most people would keep walking.When they were in business i asked for some specific details regarding the test documents they supplied but they were not forthcoming so you can read into it whatever you like,lazy,perhaps false, who knows but it didn't tick all the boxes then and doesn't now.
It was NidaCore that made this claim, not Polycore. So you made an inquiry with them about this drop test and received no answer as to specifics?

I have some inquires out now myself. I don't think they just dreamed this up.

Something is also getting clouded by the fact Now this product is produced on Australia's GOLD Coast now the boat was supposed to be dropped in the usvi Gold Coast.
Confusion over the Gold Coast reference. Gold Coast Yachts located in St Croix, USVI is a very long time builder of multihulls.
Gold Coast Yachts Custom Boat Builder ? Catamarans, Power Cats, Luxury Custom Yachts
Gold Coast Yachts - Professional BoatBuilder Magazine


It will be easier to prove this happened by looking for a crane that could actually do such a job they are few and far between would be worth millions and cost 100's of thousands to even set up , all to demolish a boat that would take a chainsaw a few hours.
Don't recall exactly what equipment Gold Coast themselves had to launch and retrieve their many builds, but I'm sure they they had some. There was also some very big container cranes on the island that had a substantial refinery located there. We used one of these big container cranes to offload our little Firefly 26 trimaran that was shipped down to a customer there....big overkill....ha....ha, but BIG crane


Why so much involvement in a failed company???? are you now the seller or producer of this product and using this forum to get it off the ground again.
Don't know what you are talking about?
I ignored this PP core material for years, and now I have a new appreciation for it. There are MANY naysayers such as yourself that need a little nudging,....or I more than willinglt will take their point of view into consideration about utilizing this material. I'm trying to sort thru the 'junk' and substantited

In latter years the company turned to making panels for truck trailers and vans , so they should have been successful if the product worked as well as they claimed. i saw a truck that had smashed and the "panel wreckage" would not support the claims of the "dropped boat".
I have also seen truck trailers constructed in a sandwich core type method, and I submit that this 'totally unsupported internally box' type structure would not be a fair comparision.

[44'cruisingcat]

If this claim were true, polypropylene honeycomb would be THE building material of choice for absolutely EVERYTHING. Why waste all that money on Carbon fibre? Why build ships from steel?

Funny thing is, Brian, you could prove to yourself that the story is false by simply getting hold of a sample.

Also, the article states the boat was entirely cored with Nidacore, "less the hull bottom". So what was that made of? Clearly the hull bottoms would also have to be virtually indestructible as well.

Quite simply, there is NOTHING you could build a 65 foot, 20 tonne boat from, that could withstand being lifted 50 feet in the air, then dropped onto concrete, without damage. NOTHING.

I'm amazed anyone could give this story even the slightest credence.

[44'cruisingcat]

Another thought. Presumably all valuable parts, engines etc. would have been stripped, leaving just a bare hull. 50,000lbs for a bare hull, even one 65 feet long is heavy. For a cored fibreglass hull it's ridiculously heavy.