Responded to a mayday. Vessel lost.

[Marathon1150]

Originally Posted by Factor

Boats with plastic windows. Silly concept.

Acrylic plastic, often used for boat portlights is 17 times stronger than glass and doesn’t shatter if and when it does break. Not as strong as steel or most other metals but has the advantage of transparency, hence their greater utility in this kind of application.

[s/v Jedi]

Originally Posted by Marathon1150

Acrylic plastic, often used for boat portlights is 17 times stronger than glass and doesn’t shatter if and when it does break. Not as strong as steel or most other metals but has the advantage of transparency, hence their greater utility in this kind of application.

Indeed, that post showed some inaccuracies about plastic windows. I would have expected something like “Plastic windows on plastic boats and glass windows on steel boats”

Many don’t realize that fiberglass boats are plastic boats. FRP stands for Fiberglass Reinforced Plastic.

[Chotu]

Originally Posted by Marathon1150

Acrylic plastic, often used for boat portlights is 17 times stronger than glass and doesn’t shatter if and when it does break. Not as strong as steel or most other metals but has the advantage of transparency, hence their greater utility in this kind of application.

Yeah. That was quite uninformed:

https://m.youtube.com/watch?v=FvKaXzfcrp0

That’s what I have. Lighter too.

The devil is in the mounting. Especially if you have a noodle of a boat with a thin/flexible hull. Then it’s hard to keep the plastic window (or glass) in place if it’s not mechanically captured or through bolted.

The issue isn’t what the port/window is made from as you can clearly see with the pick axe it’s actually stronger (more impact resistant) than a fiberglass hull. The issue is putting windows down low on a flexible noodle hull where the builder is building to a price point and trying to maximize profits for shareholders.

Moreover, they are not using frames or bolts because they want to sell the boats and need them to look sexy. Once the flex of the thin hull exceeds the pull on the goop/adhesive/sealant they used to glaze the window, it pops out and falls in the water.

That’s what happens. It’s not breaking. It’s detaching.

One simple way to understand: they don’t make bulletproof fiberglass boats. None are bulletproof. However, Lexan/polycarbonate is the material used for bulletproof glass

Note: glass ones will have the same problem popping off flexing thin hulls but they are more prone to breaking so they aren’t used.

[MicHughV]

This happened recently on our local beach. It was a cumulative series of events that put the boat there. It has since washed up beyond the high tide line due to some inclement weather and there is no hope in getting it off again.

Local authorities are making plans to demolish it and get it off the beach.

[MicHughV]

forgot to add photo ....my bad

[sailingharry]

Originally Posted by Chotu

A flexible noodle hull where the builder is building to a price point and trying to maximize profits for shareholders.

Moreover, they are not using frames or bolts because they want to sell the boats and need them to look sexy.

A flexible noodle of a hull is not exclusively a "bad thing." It is a result of making a lighter, and therefore faster, hull. And typically a more affordable hull. If affordability was not a concern, we'd all have carbon fiber hulls, and the boats would be stiffer.... errr, not -- 'cause we'd leverage the stronger material into an even lighter, faster boat! Find me a carbon fiber hull that weighs as much as a comparable glass hull (hull, not total boat weight -- the weight savings is often moved to the keel) to prove me wrong! No doubt, a skinned balsa core hull is not as strong as the boat I grew up on (40' hull with glass over 3" thick in places) or even my 1979 Sabre 34 (glass close to 2" thick in places) but it is well suited for the job and much lighter/faster (and warmer too).


Maximize profit to shareholders is a bit misleading. Cost cutting does not normally accrue 100% to the shareholders. It does make for affordable boats as well -- which, of course, sells more and makes more profit. If Beneteau doubled the price of their boats (by doubling the manufacturing costs), they'd have a boat as good as an HR -- and sell about as many as HR sells!



Sexy. Yeah. That's a problem for me all over the place. I'm looking for a new car, and every car I look at has traded function for style. I'm going to grab an arsenal and go visit an auto design office and tell them I'm not leaving until they design one that is functional! LOL.

[Chotu]

Originally Posted by sailingharry

A flexible noodle of a hull is not exclusively a "bad thing." It is a result of making a lighter, and therefore faster, hull. And typically a more affordable hull. If affordability was not a concern, we'd all have carbon fiber hulls, and the boats would be stiffer.... errr, not -- 'cause we'd leverage the stronger material into an even lighter, faster boat! Find me a carbon fiber hull that weighs as much as a comparable glass hull (hull, not total boat weight -- the weight savings is often moved to the keel) to prove me wrong! No doubt, a skinned balsa core hull is not as strong as the boat I grew up on (40' hull with glass over 3" thick in places) or even my 1979 Sabre 34 (glass close to 2" thick in places) but it is well suited for the job and much lighter/faster (and warmer too).


Maximize profit to shareholders is a bit misleading. Cost cutting does not normally accrue 100% to the shareholders. It does make for affordable boats as well -- which, of course, sells more and makes more profit. If Beneteau doubled the price of their boats (by doubling the manufacturing costs), they'd have a boat as good as an HR -- and sell about as many as HR sells!



Sexy. Yeah. That's a problem for me all over the place. I'm looking for a new car, and every car I look at has traded function for style. I'm going to grab an arsenal and go visit an auto design office and tell them I'm not leaving until they design one that is functional! LOL.

OK I agree with lots but there’s one thing I have to point out..

Stiffness comes from thickness. Nothing else. That’s it. Structural integrity comes from the skin on the hull. That’s the whole concept of a cored hull.

A noodle is not the inevitable outcome of a lightweight hull. I very carefully pored over all of this before building my boat. Using too thin a laminate is the only reason a hull is a noodle. My boat is the stiffest boat I’ve ever been on. Why? The hull is an inch thick everywhere and bulkheads are placed like it was 3/4” thick. . Nothing moves at all in even the worst chop. It’s also very very light as you know.

So I just wanted to point out that having a noodle is just bad design. It’s not the inevitable outcome of lightweight boats. It’s the inevitable outcome of having too thin of a laminate.

Also I was not really being 100% serious about the shareholder thing. That’s just kind of a colloquialism. It’s commonly used. What I mean is they could be doing a lot better job building the boats

[BlueH2Obound]

Originally Posted by sailingharry

If you are using Firefox, you can toggle "reader view." It's the far right of the address bar, right beside the star. It looks like a sheet of paper. It serves the page up with no features, and often defeats the paywall (for sure on this link it works).

Thanks so much for that tip! Worked like a charm! I learn something new everyday, even when I try not to . . .

[Bowdrie]

[QUOTE=Chotu;3845200]
Stiffness comes from thickness. Nothing else. That’s it. Structural integrity comes from the skin on the hull. That’s the whole concept of a cored hull.

So I just wanted to point out that having a noodle is just bad design. It’s not the inevitable outcome of lightweight boats. It’s the inevitable outcome of having too thin of a laminate. /QUOTE]

You're right.
For stiffness the value of thickness is cubed.
Double the thickness=8 times the stiffness.
Noodles? We used to call them "Flexy Flyers".
Exotic materials aside, many years ago it was determined that if you built a single-skin hull using well known "Scantling Rules" the stiffest was welded aluminum, and close behind it was cold molded wood.
Fiberglass is quite flexible and unless massively thick, (and heavy,) stiffness comes from a core.
No matter the material, for a single-skin hull the biggest increases in both stiffness and overall strength relative to weight comes from longitudinal stringers.

[GordMay]

Originally Posted by Chotu

... Stiffness comes from thickness. Nothing else. That’s it. Structural integrity comes from the skin on the hull. That’s the whole concept of a cored hull.

A noodle is not the inevitable outcome of a lightweight hull...

Stiffness is proportional to the cube of the thickness, for a flat plate, of a given strength.
A curved plate, like a boat hull, would be more complex.

The terms strength and stiffness often are used interchangeably, but they have different meanings and significance.

Strength is a measure of the stress that can be applied to a material before it permanently deforms (yield strength) or breaks (tensile strength).

Stiffness relates to how a component bends under load while still returning to its original shape once the load is removed.
Stiffness of a component is a function of both material [Young’s modulus of elasticity], and geometry [thickness, etc].

Young’s Modulus for steel [29 million PSI] is three times that of aluminum [10 million PSI]. This means that for a fixed geometry, a part made out of steel will be three times as stiff, as if it were made out of aluminum. In other words, an aluminum part, under load, will deflect three times as much as a similarly loaded steel part.

For instance:
To neutralize aluminum being one-third the stiffness of steel, an aluminum part must be made 44 percent thicker, than the steel part. Even with this increased thickness, there is a potential for weight savings, since aluminum is one-third the density of steel.
The same holds true for composite hulls, where a very lightweight core separates the FRG skins.