The new era on chainplates..

[UNCIVILIZED]

Does anyone know where the high failure rate number for stainless chainplates is coming from? And is it taking into account plates being replaced before rigs fall down?

Which begs the question, if someone does even half way decent maintenance on their boat, then why the high chainplate faiure rate? Seems about as smart as driving your car until the tiress are naught but belts with no rubber left, & then blaming the tires/tire manufacturers for them failing. AKA lawyers trying to collect on (obvious) user error.

Thus my query on where the numbers come from, how they're collected, what the circumstances are, etc.

[TeddyDiver]

Originally Posted by UNCIVILIZED

Does anyone know where the high failure rate number for stainless chainplates is coming from? And is it taking into account plates being replaced before rigs fall down?

Which begs the question, if someone does even half way decent maintenance on their boat, then why the high chainplate faiure rate? Seems about as smart as driving your car until the tiress are naught but belts with no rubber left, & then blaming the tires/tire manufacturers for them failing. AKA lawyers trying to collect on (obvious) user error.

Thus my query on where the numbers come from, how they're collected, what the circumstances are, etc.

Dunno the numbers but SS parts including chianplates have limited life span with high cyclic loads. Inspection doesn't necessarily reveal when they should be replaced and eventually they fail. Looks good but aint..
Reckon SS stays and bolts in the rigging together with the chainplates are the main reason in most cases.
Just IMHO, Teddy

[a64pilot]

Sometimes chainplates maintenance, replacement of standing rigging etc. is not an inexpensive proposition, combine that with the average age of boats and their net worth and what owners have to spend and or willing to spend, and no requirement to maintain them, and you have 30+ yr old boats that get no maintenance.
That along with the fact that from outside appearance they look fine, and the average older boat owner may not even know this stuff has limited lifetimes, and the attitude of "that's what Insurence is for" and you get to where we are.

It may get worse for our multi hull friends as they begin to have a high number of old boats, I don't believe the average mono's rigging sees the stresses possible in a multi?

Insurence companies will I guess be the ones that will cause a change maybe, by refusing to insure boats with rigging older than X number of years old?

[Kudawudashuda]

Just an observation, but this is a cruising forum, not a racing forum. So it doesn't matter what your chainplates are made from because if one fails you will have several other supporting the mast, just as you will have a collision bulkhead, independent fuel systems, spare anchor and rode, a veritable chandlery of spares, etc, etc. And they probably won't fail because you will have fitted only elements that are easily inspected and were replaced well within the predictable lifespan.

[neilpride]

Originally Posted by Kudawudashuda

Just an observation, but this is a cruising forum, not a racing forum. So it doesn't matter what your chainplates are made from because if one fails you will have several other supporting the mast, just as you will have a collision bulkhead, independent fuel systems, spare anchor and rode, a veritable chandlery of spares, etc, etc. And they probably won't fail because you will have fitted only elements that are easily inspected and were replaced well within the predictable lifespan.

So if a capshroud chainplate fail, the mast dont fall down?

[Snowpetrel]

My brother built his 8.5m racing tri with carbon fibre chainplates, beam mounts and rudder pintles, all in a garage with nothing fancier than carbon unidirectional cloth, epoxy and peel ply. They are so massively overspeced that fatigue isn't an issue. And being inboard and tied to plywood bulkheads impact damage is unlikely. The biggest future issue will likley be with the ply bulkheads, not the carbon chainplates https://youtu.be/JvCopAEc0E8

On the remote repair issues, where there is a will there is a way, remember Yves Parlier's incredible vendee globe carbon fibre mast repair while at anchor in the remote Stewart Island south of NZ.

http://www.thmartinez.com/folio/339/...es-images.html

We replaced both welded in chainplates on an old aluminium open 60 in the falklands (due to fatigue failure). It was a bit of a nightmare as the welding gear (MMA stick welding, due to no argon being available) and the positions for access where very awkward. Glassing in new CF chainplates would have been much easier.

[Stumble]

Originally Posted by UNCIVILIZED

Does anyone know where the high failure rate number for stainless chainplates is coming from? And is it taking into account plates being replaced before rigs fall down?

Which begs the question, if someone does even half way decent maintenance on their boat, then why the high chainplate faiure rate? Seems about as smart as driving your car until the tiress are naught but belts with no rubber left, & then blaming the tires/tire manufacturers for them failing. AKA lawyers trying to collect on (obvious) user error.

Thus my query on where the numbers come from, how they're collected, what the circumstances are, etc.

Which number?

The 40% number i threw out is what I remember about the causes of rig failure, probably from an insurance report. So about 40% of the time if the rig fails it's because of the chainplates. It won't tell you anything about how often rigs come down.

As for how many chainplates fail... depends on the boat. IP's have close to the stupidest chainplate designs out of the factory I have ever seen. I would guess that at 20 years they have a 50% failure rate. A standard penetrating bar is probably 5%. The USCG has some good guidance on chainplate inspections, and again from memory at 12 years they are supposed to be pulled for NDA. Then every four years until they are 20, then it's NDA every year.

[44'cruisingcat]

Originally Posted by Kudawudashuda

Just an observation, but this is a cruising forum, not a racing forum. So it doesn't matter what your chainplates are made from because if one fails you will have several other supporting the mast, just as you will have a collision bulkhead, independent fuel systems, spare anchor and rode, a veritable chandlery of spares, etc, etc. And they probably won't fail because you will have fitted only elements that are easily inspected and were replaced well within the predictable lifespan.

But isn't it preferable to have chainplates that will never leak, never need replacing, will last the life of the boat?

[SVNeko]

Why does everyone keep talking about "inspection"? The beauty of integral composite chainplates are that they are engineered into the boat as part of it. Do you go around inspecting bulkhead tabbing or your deck layup planning to replace them at periodic intervals?

[barnakiel]

Originally Posted by Kudawudashuda

Just an observation, but this is a cruising forum, not a racing forum. So it doesn't matter what your chainplates are made from because if one fails you will have several other supporting the mast (...)

?

Kuda,

But if the capshroud goes, what happens?

And on a typical Bavaria or Hallberg Rassy two spreader Selden swept rig, if one of the laterals goes, what happens?

Believe me or not, many modern boats do not even have a second forestay attachment, let alone having a second forestay! ;-) Yep.

Let alone multi-point chainplates that anchor 2 or more laterals. ;-) Yep.

We are in Canary Islands where hundreds of boats arrive every year, about a dozen or so without their rig. I always try to get a glimpse and talk to the owners. It IS actually nearly always just one wire or anchor point that goes. Then the whole thing colapses.

You are right there are better ways to design and set up the standing rigging. But most cruising boats do not use them.

barnakiel

[barnakiel]

It is also my gut feeling that the chainplates, if executed in the molding process as one piece with the hull, will require 'zero' maintenance. Of course you always look at the adjacent area as well as at the protruding part - should you find any cracks or otherwise signs you will start to wonder.

Nothing to replace, nothing to leak, nothing to corrode. The beauty of it.

b.

[minaret]

All the integral carbon chainplates I've built had a titanium thimble at the top for the actual rigging attachment point. This means the laminate does not replace the chain plate so much as it replaces the chainplate bolts, imho. This is because GRP is not sufficiently abrasion resistant for a rigging pin, therefore a metal (preferably titanium) fitting is required to be glassed in as the attachment point if you don't want to experience failure due to the pin chafing through the glass. Just replacing your standard SS chainplates with titanium is a simple upgrade which will produce similar results on most older boats. Also, turning down a titanium thimble is very time consuming and difficult, read expensive. If you use anything less than titanium, it's not much of an upgrade. Not likely to see this grade of composite chainplate in mass produced hulls soon. Sticking a carbon chainplate to a ring frame with Plexus and a SS thimble is not much of an upgrade, IMHO. More marketing hype based on what the big race boats are doing; looks the same but isn't.

[neilpride]

Well in Europe there is a bunch of production boats starting to mould the chainplates in the hulls, X yachts or Hanse, Solaris , Oyster.. for example, obviously in a old boat dont make to much sense but i confess that I was tempted to make the retrofit in my last boat, and yeah i dont expect it to see Composite plates in a Bavaria son, but sooner or later ...........

[minaret]

Originally Posted by neilpride

Well in Europe there is a bunch of production boats starting to mould the chainplates in the hulls, X yachts or Hanse, Solaris , Oyster.. for example, obviously in a old boat dont make to much sense but i confess that I was tempted to make the retrofit in my last boat, and yeah i dont expect it to see Composite plates in a Bavaria son, but sooner or later ...........

Yep, just wanted to make the point that there's a big difference between a composite chainplate with the full layup wrapped over a fitting and then fanned out onto a solid block out in the hull or onto a bulkhead, ie wet laminated in place (which can only be done by hand in time consuming fashion) and a prefabricated composite member bonded in place on a ring frame or other structural member. If we agree with the supposition that the key structural function of a composite chainplate is to replace the bolts, ie the method of transferring load to the hull, as much as the plate itself, then the first option is obviously a vastly superior method for transferring load into the hull, due to the vastly increased bonding area. And if the metal part of the composite chainplate which is laminated in for rigging attachment is something which can corrode like SS instead of titanium or similar, the benefits there are questionable as well. Don't get me wrong, I think it's a great trend. Just people should be aware of the many factors involved instead of taking builder's glossy sheets at face value. You know the drill....

[neilpride]

Could Nitronic be fine for bushings and pins???