Construction methods??

[Kita]

I am in the process of selling my houses or trading them to fund my dream & I need info. Alot of info,many questions,can someone tell me how can I find out the construction method for different cats? As I understand some are fome core or balsa, but below the waterline some are glass & some are not. I don`t want a foam or even worse balsa below the waterline,I don`t even like the deck with balsa,but I understand weight also. One day somebody will have to fix that if it gets any water, ( a screw ) & at least I think the foam won`t rot... I am mainly looking at Leopard 40, & a lagoon 38, or an island spirit 38, those are the ones I really want to find out about,So help me out,who can I ask that KNOWS!! Thanks every body!!!

[Stumble]

I don't know for sure, but I think you are going to have a very hard time finding many cats that aren't cored decks, and most of them are going to be cored hulls as well. Of the boats you mentioned

Leopard 40 - cored above and below the waterline
Lagoon 38 - cored above not below
Island spirit 38 - cored above and below the waterline

Frankly foam vs balsa is a mixed bag. Both 'rot' however. Balsa from actual rot, foam from a process called hydrolic erosion. Either way keeping the core dry is critical to the long term health of the boat.

[Kita]

Thank you for your imput,but are you sure about the Island spirit? I looked at a 2001 37ft & he had a core from a hole saw where he had mounted something on deck & it looked like solid glass,but I did not look real close & that is why I am trying to find out.. The leopard I looked at I found out that you are right, it is cored above & below the waterline & I will pass on that type of construction. Love the boat,but if something happens & you get water in there, it has to wick up to a point & a small spot that could be fixed easy with glass could be a much bigger job with a cored hull. Also I think you are right with the lagoon, cored above the waterline & I am ok with that.. But is it wood or foam? I also understand they both need to stay dry inside,I was just wondering. I most likely will buy a lagoon 38 even though I like the leopard but I don`t like the cored hull below the waterline at all!! I plan on spending many years with the boat & odds are at some point I will need to do something below the waterline.. A repair of some sort, I think it would be kinda cocky to say I will travel the world & NEVER bump anything!! Odds are against that. I hope not to, but just trying to pick witch one for me.. Where can I find out for sure?

[gspeak]

It is well documented that the Lagoon 380 is solid glass below & balsa core above the waterline. Just rock on over to the LagoonCatOwners forum & do a search.

There are photos of cores above & below etc. from owners that have added through hulls etc.

We have a 2004 L380 #241. I think that there are now close to over 800 of the L380's that have been built. Don't quote me on that.

Dave
Seabreeze L380 #241

Originally Posted by Kita

Also I think you are right with the lagoon, cored above the waterline & I am ok with that.. But is it wood or foam? I also understand they both need to stay dry inside,I was just wondering. I most likely will buy a lagoon 38 even though I like the leopard but I don`t like the cored hull below the waterline at all!! I plan on spending many years with the boat & odds are at some point I will need to do something below the waterline.. A repair of some sort, I think it would be kinda cocky to say I will travel the world & NEVER bump anything!! Odds are against that. I hope not to, but just trying to pick witch one for me.. Where can I find out for sure?

[ozsailer]

Hi Kita,
I am going through the exact same dilema at the moment. We have a wonderful 38 centre cockpit but due to health reasons we have been considering going to a catamaran due to the ease of getting around.
Long story short but our "solid" fibreglass hull was not solid having a foam/coremat type core above and belown the waterline which had severely delamintated. It was touch and go wether to repair the boat and take our losses or go into debt and just have a loss but not such a big one. We eventually fully stripped the hull of all core material and completely re fiberglassed and faired the hull. We are more then happy with the result ( now 18 months later ).
Having gone through this experience I am somewhat gun shy of buying any boat with any type of core below the waterline. While there are some great cats out there I love they are off my mist purely because of the core below the waterline. Maybe I am a bit old fashioned but its my hard earned bucks that end up paying the bills and if I can reduce the risk of falling foul of this type of issue again I will.

[gspeak]

Originally Posted by gspeak

It is well documented that the Lagoon 380 is solid glass below & balsa core above the waterline. Just rock on over to the LagoonCatOwners forum & do a search.

There are photos of cores above & below etc. from owners that have added through hulls etc.

Dave
Seabreeze L380 #241

I just read my reply again & I realise that it may be misleading. I meant to say "There are photos of "sample" cores above & below etc. from owners that have added through hulls etc."

Meaning that the "sample" cores show solid glass below the water line & balsa cored laminate above the water line.

Dave
Seabreeze L380 #241

[Kita]

I looked at a leopard 40 & love the boat, but I walked away because it is cored below the waterline. I don`t want to go through what (Ozsailer) went through. Thank you Ozsailer for confirming my fear. Its a shame cause I like the leopard..I guess I am old fashioned as well.. The lagoon 38 owners model is winning the search.

[ArtM]

The ideal hull:
Lightweight
Strong
Flexible (but not too flexible)
Inexpensive
Easy to repair
Difficult to damage
Impervious to rot

Keep in mind that if a construction method existed that met all these requirements, it would be the only construction method in use today.

I haven't read Ozsailer's story, but in general keep in mind that a lot of "horror" stories are self-inflicted. People fixing rot that can be safely ignored (for a while), ignoring small problems until they become big problems, and intentionally doing a DIY job that really could and should have been done professionally just for the "fun" of it.

[Stumble]

Kita,

If you go to the Island Spirit website they discuss the construction methods they use.

I haven't done an exhaustive survey, but of the boats being built now, I don't think more that 1 or 2% are built with solid glass decks. The problem is weight, and there is no easier way to eliminate weight than core a deck.

The problem as many have found out is that factories do a poor job of sealing hardware above the waterline (I actually haven't seen a core problem in the hull strangely enough). If it is a concern, the easiest way to settle it is spend a few days removing every piece of deck hardware from the boat, ensuring you have a proper epoxy plug, and adding one where there isn't. It's a pain, but it is also a good way to identify every piece of gear that needs repair/replacement, and a good way to id corroded bolts that will give problems down the road.

[Factor]

Just remember that solid glass isn't actually solid, its a matrix of fibres soaked in a resin, and it to can have its problems, primarily osmosis. It also has no give and is very open to load impact transfer - that is hit it one side and have a big fracture the other. Cores offer weight saving, insulation and some impact mitigation.

If you were going to build a boat from solid glass you may as well use metal. A 45 foot cat made from solid glass totally would be way way way heavier than an aluminium cat.

[Glenn C]

I researched material properties very carefully before building my Airex foam cored Roberts 36 in the late 70's, One of the key factors in choosing airex was the superior impact resistance offered by a properly constructed cored hull compared to solid glass, WEST system etc.

As I recall balsa had superior compressive strength, but I didnt want the possible issues with rot if the skin integrity was breached
.
I also used Airex in sections of the deck, but was careful to keep panels small and used marine ply for any areas with high compression loads. Reason for the smaller cored areas on the deck was due to designing for expected heat loads and possible creep. Suffice to say the boat lived in the tropics for most of its life and suffered no deck issues.

Of course like anything, if its not well constructed, then there can be delamination issues, etc. By the way my boat is on its 3rd owener and off for another pacific cruise.

[ozsailer]

Just in response to Art M's reply. Yes some issues are owner inflicted but in my case is was most definatley construction. It was clear that the problem started with the layup when the boat was first built. I have no issue with any boat being cored above the waterline but its just been my case where I was in a boat yard for so long I saw way to many boats cored below the waterline having issues, most with just an islated area but one boat core was totally waterlogged.
I accept the known features of a lighter boat, its just I dont want to go out and spend a large amount of hard earned cash which could cost me way more in the future. I am more then happy to be convinced otherwise

[beiland]

Since you are on the 'research path', I would suggest you look up subjects having to do with Nidacore,...for instances here is one

http://www.cruisersforum.com/forums/...ong-22948.html

I ignored this material for years, but I'm now convinced it is a most viable one. Too bad Nidacore Corp got bought out, but there are some other sources.

You might also google 'nida core', 'nidacore'. Happy reading

[barnakiel]

I think you just contact the boatyard and ask.

b.

[tuskie]

Kita, core type, and whether or not it extends below the waterline, are important factors in choosing a cat. There are many, many other factors as well, however.

Bridge deck clearance, for example, or the lack of in the case of the Island Spirit and some Simonis designed Leopards would be something that concerned me.

In the real world, both Lagoon and Leopard are constructed to take the knocks and bumps that charter boats are forced to endure from inexperienced skippers. Even though Leopards are constructed from cheap materials ie. polyester resined GRP with a balsa core, they have a generous thickness of GRP on the outside of the core that seems to protect it from the outside world. The owners and charter people that I have asked report that wet core or osmosis are not problems for these brands.
My 2 cents worth