Oyster Problems?

[neilpride]

Amel glass the joint to from inside, anyone notice a single leak in a Amel?

[robert sailor]

Originally Posted by jmaja

So you know that Bavarias are designed to need the deck bulkhead joint and are not stiff enough because it is not tabbed?

My earlier boat was made by a very small Finnish-Estonian builder that was bancrupted more than 10 years ago. It was a modern design with many rather new design features for a C/R boat designed by a young designer. It also had a steel grid, which was only glued to the hull (+ keel bolts).

I'm suggesting that when you don't join the bulkhead to the deck it's never as strong than if you do. My C&C was strong enough but very flexible, something that only showed up in offshore sailing in larger seas. Most people at that time felt C&C was a top of the line boat builder, I owned 2 of them and really liked them, especially for racing so I'm not bad mouthing any builder, I just think if your going to be doing lots of offshore sailing you might want to spend another nickel or two and buy a better boat.

[Polux]

Originally Posted by neilpride

The loads in a car are a diferent animal compared to a boat subject to a worst environment.... I don't see any posible comparison..

Are you sure?

https://www.youtube.com/watch?v=gZzKMFwMvu8

"Since that time the cars have become increasingly dependent on these materials such that a contemporary chassis may consist of up to 80% by weight of carbon fire reinforced epoxy resins and the appropriate adhesives to facilitate fabrication. One might argue therefore that a modern Formula 1 chassis consists of a series of “plastic” mouldings held together with glue!" ...
Adhesives are being increasingly employed in the assembly of complex components within the Formula 1 industry. In particular they are used to replace or augment more traditional joining techniques such as welding, mechanical fastenings and interference fits etc"
http://www.gef.es/Congresos/22/pdf/45.pdf

[neilpride]

Well I never see a F1 falling from the top of a wave?? or pounding to weather.... Lol.

[Polux]

Originally Posted by robert sailor

I'm suggesting that when you don't join the bulkhead to the deck it's never as strong than if you do. My C&C was strong enough but very flexible, something that only showed up in offshore sailing in larger seas. Most people at that time felt C&C was a top of the line boat builder, I owned 2 of them and really liked them, especially for racing so I'm not bad mouthing any builder, I just think if your going to be doing lots of offshore sailing you might want to spend another nickel or two and buy a better boat.

You seem to generalize your experience with a particular model of C&C to all light boats. Boat building and the structure of the boat varies from builder to builder but all thinks being equal a bonded deck to hull structure will provide a stiffer boat than a deck bolted.

On those articles I posted regarding the auto industry and bonding agents a common denominator is that in all of them it is said that increases stiffness and in fact it is easy to understand why (it is also refereed on the articles).

A cruiser racer is generally a lot stiffer than any other type of boats. Stifness is important to racing on cars or boats. I don't know why the C&C you had were not stiff (as opposed to flexible) but that is not the norm in what regards performance boats even if we cannot say the same regarding many mass production main market boats, specially bigger ones.

[Polux]

Originally Posted by neilpride

Well I never see a F1 falling from the top of a wave?? or pounding to weather.... Lol.

It seems you did never went fast on a car on a track. Even on an incomparably less powerful car, the shaking, the vibrations, the very fast pounding and the gravitational efforts are huge. Much more aggressive to a bonded structure then the relatively soft pounding to weather or even falling from a wave.

[robert sailor]

[QUOTE=Polux;2056784]You seem to generalize your experience with a particular model of C&C to all light boats. Boat building and the structure of the boat varies from builder to builder but all thinks being equal a bonded deck to hull structure will provide a stiffer boat than a deck bolted.

On those articles I posted regarding the auto industry and bonding agents a common denominator is that in all of them it is said that increases stiffness and in fact it is easy to understand why (it is also refereed on the articles).

A cruiser racer is generally a lot stiffer than any other type of boats. Stifness is important to racing on cars or boats. I don't know why the C&C you had were not stiff (as opposed to flexible) but that is not the norm in what regards performance boats even if we cannot say the same regarding many mass production main market boats, specially bigger ones.[/QUOTE

Actually the C&C 36 was a stiff boat and anyone who raced them would agree.

[neilpride]

Originally Posted by Polux

It seems you did never went fast on a car on a track. Even on an incomparably less powerful car, the shaking, the vibrations, the very fast pounding and the gravitational efforts are huge. Much more aggressive to a bonded structure then the relatively soft pounding to weather or even falling from a wave.

May I ask and you? do you drive to the extreme a F1 to have the knowledge about G forces and all the bla bla....

[TeddyDiver]

Originally Posted by Polux

It seems you did never went fast on a car on a track. Even on an incomparably less powerful car, the shaking, the vibrations, the very fast pounding and the gravitational efforts are huge. Much more aggressive to a bonded structure then the relatively soft pounding to weather or even falling from a wave.

I'd like to see a race car doing one RTW. We speak about decades of use throw multiple owners some with extended cruising and some with years of sitting in the sun unused in between. Decay and fatique might take their toll I'm afraid. For a cruising sailboat you might find something more appropriate to compare with than a F1 race car.

BR Teddy

[Polux]

Originally Posted by neilpride

May I ask and you? do you drive to the extreme a F1 to have the knowledge about G forces and all the bla bla....

No, but I had driven some fast cars including Ferrari. Once a friend of mind ask me to slow down saying that his brain was rattling inside his head

I know that the forces, vibrations and and accelerations on a F1 are incomparably bigger so I had an idea of the stress the car has to sustain.

A sports car sustains accelerations, lateral and braking on the order of 1g. A F1 takes 4G to 5G including lateral ones, mixed with lots of vibration and fast frequency shocks. So yes I have a pretty idea of how hard that should be on the car structure, bonded or not.

I doubt very much that the bonds on a sailing yacht would have anything closer to the stress that a F1 subjects them, or a fighter airplane, for that matter.

Anyway it is very funny since they had the same problem with clients distrust regarding bonding agents in the car industry :

"Initially, automakers didn't have the courage to admit that certain parts and sectors of the car require bonding. That's well and truly over now,"
http://www.reuters.com/article/autom...0AX2VI20130605

Regarding modern boat building it seems at we are at the same point, all, including high end brands, are using them because they perform better than older techniques at some jobs but some brands prefer not to state that openly. After all the boating clients are far more conservative than car clients. ;-)

[neilpride]

Originally Posted by Polux

No, but I had driven some fast cars including Ferrari. Once a friend of mind ask me to slow down saying that his brain was rattling inside his head

I know that the forces, vibrations and and accelerations on a F1 are incomparably bigger so I had an idea of the stress the car has to sustain.

A sports car sustains accelerations, lateral and braking on the order of 1g. A F1 takes 4G to 5G including lateral ones, mixed with lots of vibration and fast frequency shocks. So yes I have a pretty idea of how hard that should be on the car structure, bonded or not.

I doubt very much that the bonds on a sailing yacht would have anything closer to the stress that a F1 subjects them, or a fighter airplane, for that matter.

Anyway it is very funny since they had the same problem with distrust regarding bonding agents in the car industry :

"Initially, automakers didn't have the courage to admit that certain parts and sectors of the car require bonding. That's well and truly over now,"
Rush to lightweight cars boosts adhesive makers | Reuters

Regarding modern boat building it seems at we are at the same point, all, including high end brands, are using them because they perform better than older techniques at some jobs but some brands prefer not to state that openly. After all the boating clients are far more conservative than car clients. ;-)

Why you don't try to be fair and compare a F1 to a VOR 60 doing a RTW , lets see who get a hard punishment in the glues , glup!!

[Polux]

Originally Posted by robert sailor

Actually the C&C 36 was a stiff boat and anyone who raced them would agree.

As I left clear on the above post I was not talking about stiff in what regards righting moment but about stiff as opposed to flexible. You said that the C&C flexed a loot while sailing on bad weather.

[Polux]

Originally Posted by neilpride

Why you don't try to be fair and compare a F1 to a VOR 60 doing a RTW , lets see who get a hard punishment in the glues , glup!!

Now you talk about comparable things in what regards efforts

[four winds]

I believe I'm correct in saying the "glue" didn't fail in this case concerning the Oyster. But rather it was a failure of the hull lamination. Possibly as a result of the record setting attempt at infusion.

The keel trunk had some movement as the lamination began to seperate in tension near to on the hull. Then the separation spread up around the hull side, shearing and peeling half the hull skin off that very large area of the topsides as the keel broke away.

I recall the picture of the hull topsides damage where the inner half of the skin was still attached or glued to the grid structure. With only a few holes clear through between the grid sections. Some of which were done during inspection on the hard.

And a later picture showed much more, even most, of the hull skin removed in those areas between the grid. There the grid is more well seen and could give the impression the grid to hull bond failed. But looking closely it is clear the inner layers of the hull lamination are still attached to the grid members.

[sailorboy1]

Originally Posted by four winds

I believe I'm correct in saying the "glue" didn't fail in this case concerning the Oyster. But rather it was a failure of the hull lamination.

Don't be tossing facts into the same old argument by the same old arguers