The not so benign Med

[Montanan]

Originally Posted by SVHarmonie

Chotu,

I do know what balsa IS and its strength relative to other materials. I stand by my statement that as far as comressive strength it is the LOWEST of all the choices you could make. Here is some data for you for compressive strength parallel to the grain:

Loblolly Pine 49.2MPa
Sitka Spruce 38.7MPa
Red Oak 46.6MPa
Yellow Poplar 38.2MPa
Balsa 14.9MPa

So there is some data courtesy of the Forest Product Institute. Do you have other data??? You are comparing balsa to other normally used core materials, but cleats SHOULD NOT BE BOLTED THROUGH CORED PANELS.

Solid fiberglass (the go-to choice for premium boatbuilders under cleats) is an order of magnitude higher than these numbers.

Exactly or as one of the posters noted, a metal hull and deck.

There should be not fittings that pass through any cored decking, the core material should be kept considerable distance away from all through fittings and hard point attachments.

With large and thick topping and backing load spreading plates on either side of the solid fiberglass.

[slug]

Originally Posted by GarthGregory

A serious contributing factor if not the main problem , is in stern to mooring , using a way to heavy a quarter warp and which also has no stretch . If one has surge from say a passing ferry , there is the surge of a yacht weighing many tons with no give in the warps . I have seen a number of yachts with cleats ripped out , both modern and old heavier built type . I have tried the heavy rubber type absorbers and have had them all break . I have now backed all my deck cleats ( S/Steel 316 - 200 x 80 x 8 mm ) and bedded them in epoxy . The studs instead of tapped to 20 mm , I have tapped them to 70 mm .More important I have binned my heavy warps from a doubled 16 mm on each quarter , down to a doubled 8 mm ,with a shorter single 6mm line for stretch - much more comfortable and quieter . The breaking strength of modern rope is VERY high . My 2 cents worth

The best way to remove surge shock loading from Short stern lines is to rig additional spring lines ... long lines led as far forward as possible ... typically beam max
Put these long spring lines on a winch and tune them tight

[slug]

Originally Posted by Montanan

Exactly or as one of the posters noted, a metal hull and deck.

There should be not fittings that pass through any cored decking, the core material should be kept considerable distance away from all through fittings and hard point attachments.

With large and thick topping and backing load spreading plates on either side of the solid fiberglass.

Core piercing fastenings don’t handle sheer well

Use oversized bushings to increase sheer resistance and cut these bushing flush to resist compression Of the core

Or plan ahead and substitute core in the area with a more appropriate material

[Reefmagnet]

I think the lines and how they are tied are more important than the cleats. When we had a waterspout (I assume) come by us a few weeks back, a large, older power boat was ripped from it's berth and ended up with a few torn out cleats sans backing. More eye opening was that the double braid lines attached to a substantial samson post had, what I would describe as "explosively", snapped.



From our boat the wind went from about 6 to 76 knots within a few seconds, reversed direction, then was gone. It's pretty obvious, considering that not one other boat broke away from it's berth, that the issue was more related to the non stretching double braid lines used to tie that particular vessel up. It's also feasible this was compounded by having too much slack left in the lines as well.


I've attached substantial backing plates to all my cleats and other load bearing deck fittings (even if the boat had managed just fine without them for 30+ years), but I do often wonder if it's the sensible thing to do. The reason being that if a cleat does let go with a substantial backing plate behind it then has the capacity to cause a lot more damage around the immediate structure.

[jimbunyard]

Though the installation and design of the cleat are sub-par, looks more like a case of operator error to me.

Since neither stud is bent, and one of the washers is distorted in a way that looks like it was pulled straight up, I'm guessing the owner tied the boat off tight, the wind came up and blew all the water out of the marina, and the boat was left hanging on the cleat.

Still, should have a substantial backing plate, but if my guess is right, the damage could possibly have been much more substantial if it had.

Though maybe that's just a new Bentoe design feature; breakaway cleats...

[peterlewis19]

Have had a good look at that photo and it definitely looks a lot older than five years. My yacht is 2008 and my cleats look newer than that!. But it is still a disgrace anybody could build in such a large cleat with so little reinforcement. P

[GarthGregory]

My Beneteau 473 (2005 ) before I strengthened the backing of my cleats - had a few horrendous surges ( bangs ) when moored - no damage , so the Beneteau system is really strong- despite some previous opinions . The wrong circumstances , will break any boat , I have seen many yachts with damaged / repaired cleats , across the spectrum of build quality . I believe we all way over spec the warps and need to learn to moor stern to better , myself included . In the Med - there seem to be 2 x schools - The Bar Tight group ,so anchor chain rigid and heavy quarter warps tight - the other school is the exact opposite , I am leaning on the tight side , but absolutely with much much lighter quarter warps with lots of stretch . In the wrong circumstances ( surge ) , something has to give , so stretch - then the warp and hopefully not the cleat / boat .

[noelex 77]

Personally, I think that bulletproof cleats are important on a long distance cruising boat. They also need to large enough to accept decent line sizes (preferably for multiple lines).

This is probably too much to expect, but perhaps with photos such as these we can shame boatbuilders into at least doing a better job. This should involve a backing plate and solid laminate where the cleat is fitted (not only for strength, but to eliminate the chance of water intrusion into the core).

Unfortunately, part of the blame lies with the boat buying public. I am sure the boatbuilders would take a little more time and trouble over the important engineering details (cleats are just one example) if potential buyers raised these issues.

[George DuBose]

When I installed mounting points for Skylark's Jordan series drogue, I built up the deck thickness to 1" in both corners of the transom. Then I installed a 3/8 x 2 x 10" stainless steel plate underneath the 3/8 x 2 x 14" tang that the drogue is fixed to.

While docked in St. Nazaire, France, Belle Isle, an ocean-going tugboat created a .5 - 1 meter wake in the small harbor there. The surge caused one 5/8" dock line to snap and bent the cleat, but didn't pull it out of the Jordan series drogue tang.

So much for strong points and good backing...

[Chotu]

Originally Posted by George DuBose

When I installed mounting points for Skylark's Jordan series drogue, I built up the deck thickness to 1" in both corners of the transom. Then I installed a 3/8 x 2 x 10" stainless steel plate underneath the 3/8 x 2 x 14" tang that the drogue is fixed to.

While docked in St. Nazaire, France, Belle Isle, an ocean-going tugboat created a .5 - 1 meter wake in the small harbor there. The surge caused one 5/8" dock line to snap and bent the cleat, but didn't pull it out of the Jordan series drogue tang.

So much for strong points and good backing...

Strong is an understatement. Wow. That’s the strongest cleat installation I’ve ever heard of. No wonder the cleat gave way first. Nice work on that.

[Palarran]

Originally Posted by chuckr

Interesting.. maybe there is more to it than just the clears .. My Jeanneau has been through a number of hurricanes when she was in Fla with winds way over 100k .. and spent 6 winters in the Med along with sailing the entire Med and Black Sea .. never had an issue .. what type of line was used for

It's absolutely crazy how many cruisers use old sailing lines as dock lines. You don't even need to see the line sometimes to know they are using them as the jerk of the boat tells the tail.

I have been caught in a surge once though that I couldn't get out of because of the surrounding boats. My 3/4" brand new docklines got so hot from the stretch they turned to glass and you could break them in half. I spent the whole night tending lines and rearranging fenders as they blew out. I think you know the harbor - Vlikadha on Santorini. It is absolutely the surge that gets boats and cleats.

[noelex 77]

Originally Posted by Palarran

It is absolutely the surge that gets boats and cleats.

Absolutely, but do we accept this damage?

Stronger cleats are not rocket science. They are just a little more expensive.

[mikedefieslife]

Originally Posted by Montanan

IMHO, thus a failure of boat component and of boat owner to place a boat at an adversity of med mooring.

What is he supposed to do? In some cases that would necessitate leaving his country as that type of mooring is all you get in some. Finger pontoons don't exist in most places in the Med.

[sanibel sailor]

The cleat and it’s attachment need to be strong enough for what comes. Despite the manual, they will be used in a variety of ways over the boat’s lifetime. Expecting loads to only be directed in an ideal direction is not good engineering. I have reinforced mine as I recall they came with only fender washers, but I will be taking another look at their adequacy.

[Palarran]

Originally Posted by noelex 77

Absolutely, but do we accept this damage?

Stronger cleats are not rocket science. They are just a little more expensive.

We, as in you - obviously not. We as including me, well, I've done my best but a cleat could rip out given the right conditions. But for the new production boats and their owners - I think they must accept it because that's the boat they bought.

It's crazy how cheap new boat cleats are - and in wrong positions and configured for poor fairlead angle (if that is how you say it?). Two years ago in Emerald Bay Marina in the Exumas of Bahamas, the swell caused 3 cleats to break on a new Fountaine Pajot. It wasn't that they tore horizontally out, the cleats are positioned so as to pull the cleat straight out.