Solid Fiberglass Monohulls, a list

[motaman9]

Originally Posted by UNCIVILIZED

Don't you get a lot of condensation problems with non cored decks?

We have a CSY 44' with solid hull and decks...no issues so far.....


Sailing somewhere.....

[clockwork orange]

While I know this thread is about monohulls it may be useful for people to understand that a boat does not really need to be heavy displacement to be built without a core, there are a lot of boats with solid glass hulls, i have owned two multihulls with solid glass hulls and cored decks, a 31 ft Gemini at 7000lbs and a Macgregor 36 at just 4000lbs. The key is to understand where you can and can not build without core. When i hear people claim ridiculous hull thicknesses i cant help but think either its either BS or its a poorly engineered boat built using the brute force and ignorance approach. Overbuilding just squanders payload on a cruising boat which is why you will often see heavy displacement boats that should have enough payload for everything you want to carry at DWL having their WL painted many inches higher. A well engineered hull will often utilize solid glass where it makes sense, ie, below the waterline where weight is beneficial and in areas of the hull with a lot of compound curvature which allows for solid glass without ridiculous thickness but then transitions to either a core or interior structure such as ribs and or stringers in areas that are flatter such as the topsides forward. I have an old Lindenberg 26 for example which is cored (Foam) above the waterline only from the bow back to the galley with everything else being solid glass about 1/4" thick. They could have used stringers instead of core forward had they wished but coring gives a cleaner interior and using foam was a wise choice. The decks are foam and trouble free and light where it matters especially important on a boat with high freeboard. This is a well engineered boat, unfortunately some of the build did not match up to the engineering. BTW, the hulls on the Macgregor 36 were also well engineered and only measure about 3/16 to 1/4" overall but are realativly massive everywhere they need to be at about 3/8". Any thicker would be stupid heavy for no gain. The reason you don't see many solid glass decks is mostly because there are very few parts with compound curvature ( think eggshell) that would allow for reasonable weight and most boats can not afford the loss of headroom that interior structure would take up.

Steve.

[neilpride]

Originally Posted by clockwork orange

While I know this thread is about monohulls it may be useful for people to understand that a boat does not really need to be heavy displacement to be built without a core, there are a lot of boats with solid glass hulls, i have owned two multihulls with solid glass hulls and cored decks, a 31 ft Gemini at 7000lbs and a Macgregor 36 at just 4000lbs. The key is to understand where you can and can not build without core. When i hear people claim ridiculous hull thicknesses i cant help but think either its either BS or its a poorly engineered boat built using the brute force and ignorance approach. Overbuilding just squanders payload on a cruising boat which is why you will often see heavy displacement boats that should have enough payload for everything you want to carry at DWL having their WL painted many inches higher. A well engineered hull will often utilize solid glass where it makes sense, ie, below the waterline where weight is beneficial and in areas of the hull with a lot of compound curvature which allows for solid glass without ridiculous thickness but then transitions to either a core or interior structure such as ribs and or stringers in areas that are flatter such as the topsides forward. I have an old Lindenberg 26 for example which is cored (Foam) above the waterline only from the bow back to the galley with everything else being solid glass about 1/4" thick. They could have used stringers instead of core forward had they wished but coring gives a cleaner interior and using foam was a wise choice. The decks are foam and trouble free and light where it matters especially important on a boat with high freeboard. This is a well engineered boat, unfortunately some of the build did not match up to the engineering. BTW, the hulls on the Macgregor 36 were also well engineered and only measure about 3/16 to 1/4" overall but are realativly massive everywhere they need to be at about 3/8". Any thicker would be stupid heavy for no gain. The reason you don't see many solid glass decks is mostly because there are very few parts with compound curvature ( think eggshell) that would allow for reasonable weight and most boats can not afford the loss of headroom that interior structure would take up.

Steve.

Mate, long time ago builders dont have the knowledge and experience with the new stuff , in any case they build this boats with stupids layups and today this boats are still sailing , some are survived to reefs, hurricanes and collisions, if a 40000 pounds boat with a insane hull ticknes make 6 or 7 knts in 15 or 20 knts of wind sounds cool to me and is enough for cruising , and here we goo again with the assumption that heavy weight boats are slow by nature, some yes and some not, we cross the pond 25 years ago in a 62 ft Steel cutter with a weight of 40 tons averaging 9 knts all the way , i can agree with you that dont make any sense anymore to build thick and heavy due new building techniques , cores, exotic materials etc... you can make a light and strong boat today, from what i see this days, solid decks are timeless, same as hulls if they get proper maintenance, core decks are something in the maintenance list same as hulls with core, something to wacht and take care, solids decks have advantages and downsides, recoring a deck is a expensive job, moisture and wet cores make the whole thing no sense, again , i will take any well made it coredeck v solid anytime, and i will take any well made it solid deck v bad core deck anytime, time put everything in place, having owned 2 core boats in the past i swicht to a solid construction, to me the only drawback is a penalty in light airs and i made some modifications to mitigate that, light sails, rigging, and deck gear, and i swear that in many cases sailing alongside to other light construction boats the diference is minimal or nonexistent, ..

To be honest if thicknes is a negative aspect in boat construction , mould liners to hide and support a weak structure is a criminal offense, and we know that FG bulkheads and stringers is endangered... you can get a wonderful foam core deck resting in a weak thin mould lined hull with bulkheads resting in plastic slots , heeee, hell yes,

Thick hulls and decks make a strong structure if is supported by proper stringers and bulkheads , weight is a isue , but the days of spruce masts and cotton sails are over, my hull is 36 years old, no delamination, moisture, oil canning or any other kind of BS , its surveyed 2 times since im the owner, and in both reports the result is satisfactory, my 2 cents that many 36 years old core hulls and decks cant say the same?

Im not a core hater , no, in fact my next boat is going to be cored,but i know this will be a expensive proposition, few brands made well designed and well enginered core boats, the rest is just playing nuts with customers, the saying about in the past builders dont know much about FG and lay FG like demons thinking how many layers need the hull to be strong enough can be twisted as today many builders are scrachting their brains thinking how thin and light the hull can be to be strong enough, hehe.

The troglodites from the past made thick and heavy hulls , and strong structures , they are still strong this days and still sailing, some yuppies in elegants offices are thinking in how to save costs and make more profit more profit at the expense of safety and proper build techniques .

Saying that both metods of construction are well suited in some circurmstances , others not.

[Cheechako]

Originally Posted by cpa

I did not post to this thread earlier as my boat's hull and deck are not 100% solid glass, maybe 99% solid glass. But I thought my experience might be helpful for others. I would like to apologize for the thread drift.

Our Compass 47 has a solid glass hull and nearly the entire deck is non cored. There is a small section on the foredeck (3x3 foot section) and the aft half of the cockpit is cored (2x3 foot section). The rest is solid glass with stringers. We had to replace the core in the cockpit, it was about as much fun as the other times I have had to replace core.

This is my first boat that is nearly core-less and I have to say I would not change it in a million years. I Have had more than a few boats (5) that had core problems and it is nice to know that I don't have to worry about it ever again. The deck is stiff and the boat is not a heavy. I feel done right it is a great way to build a deck.

This says it all... 47 foot boat with two very small cored areas... and one of them has failed!
There are two type of cored boat owners, one with a lot of soggy core and one who will have it! soon haha

[cpa]

Originally Posted by Cheechako

This says it all... 47 foot boat with two very small cored areas... and one of them has failed!
There are two type of cored boat owners, one with a lot of soggy core and one who will have it! soon haha

The funny thing is I almost replaced the good section of core on the bow with Coosa while I was doing the cockpit. I figured I will probably have to do it eventually. In the end I decided not to cut into perfectly good deck until it fails. I am pretty good about keeping on top of leaks, so it should be alright.

[TanzerTom]

Originally Posted by thomm225

Yep, I missed the bit about the cored deck. I figured he was worrying over a cored hull boat.

But the Niagara 31 has a solid fiberglass hull. The Niagara 35's hull is cored. I researched it thoroughly because there is a Niagara 31 for sale in North Carolina that I almost bought.

Thomm, I think you may be the one the recommended the Niagara in NC to me. I plan on going down to Oriental when the freeze is over to look at it, a Sea Sprite 34 and several others. Anything you can share on the N31? Looks to be pretty good visually and at Avery fair price... something must have changed your mind. Was it the Niagara or just a better alternative?


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[David_Old_Jersey]

Seadog 30
Hurley Silhouette 17!

[wgewaldii]

Originally Posted by David_Old_Jersey

Seadog 30
Hurley Silhouette 17!

Hurley became Dockrell, I believe. Mine is 27' cutter.

[keithe]

My Block Island 40 is all solid FG. It was built in 1960 or 61 by American Boatbuilding Company. The design predates, but is similar to, the Bermuda 40 by Hinckley.

[Don C L]

Bluewaterboats.org has some info on boat construction too. I love my solid 1962 Columbia 29!

[mitiempo]

The Spencer 35 has no core in hull or deck.

[Don C L]

You might also check the Challengers (32, 35 and 40, there may have been others) built in Wilmington, CA. I have heard they were built strong but have never seen one.

[olegmenshov]

Who knows something about MOODYS’, built in early 80’s ?

[svfinlandia]

Most (if not all) Nauticats have (thick) solid glass hulls. Some older ones are also solid glass decks.
My '83 NC 36 is all solid fiberglass.

Al, S/V Finlandia

[robert sailor]

Originally Posted by olegmenshov

Who knows something about MOODYS’, built in early 80’s ?

Moody is a well built boat. It is stick built with bulkheads and furniture glassed to hull and deck as well as thru bolted. Hull is solid with glassed in stringers,very well laid up..Deck is cored. Excellent glass work everywhere. Some of the older Thornycroft diesels are getting long in the tooth. World class owners group that will answer any question you have.