Bronze or plastic skin fittings and seacocks?

lustyd

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Weasel words from TruDesign. What about normal use and where the bronze is not damaged?
Then it's not an issue for either system. You can't have it both ways, insisting that TruDesign are inferior in your extremely specific made up scenario while not allowing them the same opportunity.
 

Elessar

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TruDesign use a glass reinforced plastic. We have used similar plastics to make components in plastic injection machinery in our factory. We’ve tested them and they can indeed be massively stronger than polypropylene for example. They are also massively weaker than bronze.

A countersunk/recessed thru-hull is indeed superior. I have them - particularly superior for hydrodynamics.
And what are they fixed into?
 

Tranona

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Is it less strong? Not usually. My thru-hulls go into thick solid composite, which will be stronger than the thin webs of the outside of the mushroom of the thru-hull - only 2mm or 3mm thick typically. Aren't yours built that way? Even if it went into a sandwich I think you'd find that the penetration area was strengthened very considerably.

So please say why the RCD is not applicable in the way I implied.

As to skin fitting collisions needing evidence of their capability to sink a boat, sorry, I don't have all insurance claims or accident records to hand, maybe you do for you to suggest it is not even a risk? It completely obvious that skin fitting failure can sink a boat. Really your argumentation on this is not credible!
Pot and kettle. Despite your claim about the strength of the Hull, sinkings usually occur when hull is breached in a collision. I simply asked for evidence to support your claim that collision would cause a through hull flange to fail and that a composite is more likely to fail and you can't.

As to the RCD it is consumer legislation to provide guidance to buyers and users as to the suitability of boats for their chosen use. Clearly fulfills that purpose as thousands of boats built to that standard are successfully sailing the worlds' oceans, just as similar boats built to other standards such as the ABY and US Coastguard. They may well be different from the type of boat that you would choose but that is just your opinion and not necessarily shared by others. Standards set are the minimum requirements just like any other standard, builders are free to exceed such standards if they and their customers so wish. Given the huge variety of designs and construction of boats available it is also clear that the standards achieve their objective.
 

Trident

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I would also note that the RCD is basically flaunted regularly by many boat builders (mainly French in my experience) and yet still the pass certification. It also excludes many things that cause loss of boats

You should not trust your safety to the RCD.
 

Tranona

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I would also note that the RCD is basically flaunted regularly by many boat builders (mainly French in my experience) and yet still the pass certification. It also excludes many things that cause loss of boats

You should not trust your safety to the RCD.
Some sweeping allegations there. Care to give examples, particularly of the latter claim.
 

Trident

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Some sweeping allegations there. Care to give examples, particularly of the latter claim.
Ok simple safety one - look up the maximum distance between stanchions allowed under the RCD and then go measure the distance on Lagoons that have an A rating on RCD and see if they comply. A number of such issues exist because guess which companies in which country "wrote" the directives and don't get harsh testing ..
 

Tranona

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Ok simple safety one - look up the maximum distance between stanchions allowed under the RCD and then go measure the distance on Lagoons that have an A rating on RCD and see if they comply. A number of such issues exist because guess which companies in which country "wrote" the directives and don't get harsh testing ..
Actually the Directive was largely written in the UK, particularly the critical stability standards which underlie the Categories.

Your example does not seem to be in any way related to the loss of boats - or even people. Not denying that such minor infringements don't occur, but I am old enough to remember the "standards" of boat building before the RCD came in and would not ant to see a return to those days
 

Trident

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Actually the Directive was largely written in the UK, particularly the critical stability standards which underlie the Categories.

Your example does not seem to be in any way related to the loss of boats - or even people. Not denying that such minor infringements don't occur, but I am old enough to remember the "standards" of boat building before the RCD came in and would not ant to see a return to those days
I think one could argue on an ocean category boat that weak stanchions can easily cause loss of life - but I only gave on example.

If I'm honest all I know about them have come from boat builders who have seen others regularly flout the regs which they have then had to fix etc when picked up in coding etc - I'm no expert in this but many in the industry, especially in the UK have given me examples of how poorly enforced the standards are.

I would also note this wording from surveyors " the primary aim of the RCD is to remove barriers for trade between countries, and not to ensure quality or safety or compliance with the Boat Safety Scheme requirements."

I have worked on hundreds of boats in the last few years and I would say in terms of quality of construction and strength many of those built before 94 when the EC wrote the RCD were much better than many built since.
 

Graham376

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Actually the Directive was largely written in the UK, particularly the critical stability standards which underlie the Categories.

Your example does not seem to be in any way related to the loss of boats - or even people. Not denying that such minor infringements don't occur, but I am old enough to remember the "standards" of boat building before the RCD came in and would not ant to see a return to those days

Thankfully, there are plenty of pre-RCD boats still around (mine included) and I would guess that many will still be around after some mass produced modern boats are time expired.
 

Tranona

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I think one could argue on an ocean category boat that weak stanchions can easily cause loss of life - but I only gave on example.

If I'm honest all I know about them have come from boat builders who have seen others regularly flout the regs which they have then had to fix etc when picked up in coding etc - I'm no expert in this but many in the industry, especially in the UK have given me examples of how poorly enforced the standards are.

I would also note this wording from surveyors " the primary aim of the RCD is to remove barriers for trade between countries, and not to ensure quality or safety or compliance with the Boat Safety Scheme requirements."

I have worked on hundreds of boats in the last few years and I would say in terms of quality of construction and strength many of those built before 94 when the EC wrote the RCD were much better than many built since.
Where did you say they were weak - you only said the spacing did not comply.. Coding (at least in the UK) has its own requirements that are in some ways different from RCD so often require changes. Not sure you have presented any evidence that standards are not "enforced". It is the manufacturer and its certifying body that is responsible for ensuring its products meet the standards and declare in the Certificate of Conformity. There is no third party inspection that can publish any data on non compliance. It is the same with any other product that has a CE mark.

The Boat Safety scheme is very specific to the UK inland waterways and says little about standards of design and construction. It concentrates on fuel, electrical gas and heating systems because these are the things that cause accidents and deaths on the waterways. Apart from minor issues like grounding of fuel fillers (which in itself is contentious) there is little conflict between the requirements and the standards in the RCD. If you are bored you can read them here boatsafetyscheme.org/media/299451/bss-complete-ecps-private-boat-public-version-2023.pdf The scheme was introduced because there were no standards and "old" pre RCD boats simply did not comply. Pre 1998 electrical systems were generally poor, many boats did not have drained gas lockers, unvented gas heating was common and many other items in the scheme were there to make boats safer.

The idea that older boats were better built just does not stand up to scrutiny. You only have to follow the threads on this forum over the years to see a long list of endemic issues in older boats - osmosis, constant leaks from windows and deck fittings, mild steel tanks sitting in wet bilges, collapsing mast steps, keels coming loose, rotting bulkheads, leaking and corroding chain plates, inadequate electrics to name a few more common issues. Of course modern boats are not perfect, but many of the failings of earlier boats have been eliminated by better standards, improved materials and better construction methods.
 

geem

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TruDesign use a glass reinforced plastic. We have used similar plastics to make components in plastic injection machinery in our factory. We’ve tested them and they can indeed be massively stronger than polypropylene for example. They are also massively weaker than bronze.

A countersunk/recessed thru-hull is indeed superior.
That's a different test from what we are talking about. That relates to protection from impact or stress on the thru-hull on the inside of the boat. It also does not compare the strength of bronze thru-hulls - they will be much stronger. I also think that meeting design requirements means little as they are often a low bar. For example the CE Category A Ocean category is a bit of a joke in my view and is no warranty of suitability for ocean sailing.

It is possible to make plastic parts as strong as bronze, but even a strong one like glass reinforced nylon such as TruDesign use will need a lot more material to achieve the same strength as bronze. A Google search reveals that glass filled nylon has typically a quarter to a tenth of the tensile strength of bronze depending on the alloy used. Not as tough either, by a long way.
I use Forespar Marelon glass composite valves apart from a couple of bronze valves for a specifics reason. The marelon valves are huge. I suspect a sideways force on those valves would easily match the strength of bronze.
 

Trident

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Where did you say they were weak - you only said the spacing did not comply.. Coding (at least in the UK) has its own requirements that are in some ways different from RCD so often require changes. Not sure you have presented any evidence that standards are not "enforced". It is the manufacturer and its certifying body that is responsible for ensuring its products meet the standards and declare in the Certificate of Conformity. There is no third party inspection that can publish any data on non compliance. It is the same with any other product that has a CE mark.

The Boat Safety scheme is very specific to the UK inland waterways and says little about standards of design and construction. It concentrates on fuel, electrical gas and heating systems because these are the things that cause accidents and deaths on the waterways. Apart from minor issues like grounding of fuel fillers (which in itself is contentious) there is little conflict between the requirements and the standards in the RCD. If you are bored you can read them here boatsafetyscheme.org/media/299451/bss-complete-ecps-private-boat-public-version-2023.pdf The scheme was introduced because there were no standards and "old" pre RCD boats simply did not comply. Pre 1998 electrical systems were generally poor, many boats did not have drained gas lockers, unvented gas heating was common and many other items in the scheme were there to make boats safer.

The idea that older boats were better built just does not stand up to scrutiny. You only have to follow the threads on this forum over the years to see a long list of endemic issues in older boats - osmosis, constant leaks from windows and deck fittings, mild steel tanks sitting in wet bilges, collapsing mast steps, keels coming loose, rotting bulkheads, leaking and corroding chain plates, inadequate electrics to name a few more common issues. Of course modern boats are not perfect, but many of the failings of earlier boats have been eliminated by better standards, improved materials and better construction methods.
Your last paragraph sounds like Leopard catamarans list of faults in the last few years and as for osmosis the worst I have ever heard is in post RCD FP cats . I am no expert but I work every day with modern built boats and the quality is atrocious .

The spacing of stanchions in in the RCD because it’s important to the strength of the lifelines and the safety they provide - if that is ignored it weakens the whole safety system (or not - it could be a very arbitrary rule to try and ensure better safety with no evidence that it does) but my point was manufacturers ignore it and are still selling their boats with RCD Ocean certification which makes the standard of limited value
 

lustyd

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The spacing of stanchions in in the RCD because it’s important to the strength of the lifelines and the safety they provide
The strength of guard wires is in the tension end to end. The stanchions just hold them in place. They aren’t lifelines, they’re guard wires. If you want to stay on board jack stays are the correct method.
 

geem

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The strength of guard wires is in the tension end to end. The stanchions just hold them in place. They aren’t lifelines, they’re guard wires. If you want to stay on board jack stays are the correct method.
I really don't believe that is true. You should be able to pull yourself up the guardwires to climb back on board. Lots of boats fail this test. Stanchions fixed to the deck with 3 self tappers still seem to prevail. It's a very poor solution. What's wrong with having the primary guard wire system strong enough to support you and the jack stays to halt your progress should you fall over the top?
 

Trident

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The strength of guard wires is in the tension end to end. The stanchions just hold them in place. They aren’t lifelines, they’re guard wires. If you want to stay on board jack stays are the correct method.
In the USA they're lifelines - and pedantry adds nothing to the discussion :D So why do we suppose there is a written regulation as to the placement of stanchions ? It is to ensure the unsupported length of guard wire between stanchions is not too long. Of course if its not tight it matters not how many stanchions support it and I said above it could well be arbitrary with no actual safety testing - I don't know. However, if you write a rule that says placement must be no more than x and builders regularly use x +1 but get the certification anyway, then there is a problem with the system.

And as I quoted above - the main reason for the RCD was to "remove barriers to trade" not to ensure better boats were built.

I'm not saying it is a bad thing or unfit for purpose, just that buying a boat based on a manufacturer saying this is Class A etc does not mean it is safe or fit for the purpose of crossing oceans and further research and surveys should be done.
 

Trident

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I'm not sure there is any real argument here on seacocks . Most agree that modern composites like TruDesign have many advantages.
One or two say that high quality bronze is in their opinion better . I disagree but no one is going to be ill served by a high quality bronze seacock in the right hull material.
A bigger issue is perhaps the number of poor quality bronze fittings available and how difficult it is for most of us to tell which is good and which is bad. For that reason alone I'd suggest people choose TruDesign composites ... until such point I guess, as who the Chinese flood the market with cheap composites that look the same
 

lustyd

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I really don't believe that is true. You should be able to pull yourself up the guardwires to climb back on board. Lots of boats fail this test. Stanchions fixed to the deck with 3 self tappers still seem to prevail. It's a very poor solution. What's wrong with having the primary guard wire system strong enough to support you and the jack stays to halt your progress should you fall over the top?
Nothing wrong with them being strong enough, but relying on them is a folly since you can't (or shouldn't) clip onto them so they rely on you catching yourself on a thin piece of taut wire. A Jackstay is designed to be clipped onto so the person doesn't need to do anything to stop a fall, especially if they keep to the high side of the boat. Ideally (on a monohull) the tension of the wire will be pulling in on the stanchion so when it's pulled outwards it's not relying on just the bolts. Cats are straighter at the sides so may not benefit from this as much.
 

geem

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Nothing wrong with them being strong enough, but relying on them is a folly since you can't (or shouldn't) clip onto them so they rely on you catching yourself on a thin piece of taut wire. A Jackstay is designed to be clipped onto so the person doesn't need to do anything to stop a fall, especially if they keep to the high side of the boat. Ideally (on a monohull) the tension of the wire will be pulling in on the stanchion so when it's pulled outwards it's not relying on just the bolts. Cats are straighter at the sides so may not benefit from this as much.
Why would you clip onto them? You have jackstays for that. They should allow you to fall on them without breaking though
 
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