Oyster Problems?

[olaf hart]

Pop rivets??

[Just Another Sa]

Originally Posted by minaret

Do you think maybe the recession is molded in? Why would they cut out all the glass in that area instead of just glassing over it? It'd be a substantial extra step for a negative result. Certainly they didn't machine that recession in place, which would have to be the case for what you are saying to be true.

If the laminate near by is 1,8 mm outer skin and 1,2 mm inner, and the core inbetween, isn't the easier way to do it involve making it single skin lamination for the leg area, thus 3 mm total without any extra unnecessary reinforcement, for non structural and nonwatertight area for sreamlining flow. Obviously the enginebed carries the loads and spreads them out.

[jmaja]

In Sydney Hobart race the conditions have been tuffest since 2004 and 29% of the boats have retired, but all the 9 Beneteau's (First 40-50 foot) are still racing.

[Polux]

Originally Posted by jmaja

In Sydney Hobart race the conditions have been tuffest since 2004 and 29% of the boats have retired, but all the 9 Beneteau's (First 40-50 foot) are still racing.

Not only racing but some of them pushed to the limits doing a hell of a race being among theoretically much faster carbon racers or much bigger boats, I am talking about Imagination, a First 47.7 that is racing on 21th place in 77 boats having close ahead the first of the several 70ft clipper racers and has behind Hartbreaker a Carbon racer, a Rogers 46, Ocean Affinity a Carbon Marten 49 and a modern Swan 62.

Talking about Mayfair, a First 40 that is racing on 30th place, between the 2th 70ft clipper racer and the 3th, ahead of After Midnight a racing Farr 40 and all other 70ft clipper racers.

Talking about Black sheep, a First 45 that is racing in 43th place, chasing Midnight Rambler, a very fast racing ker 40 and having behind Kaile, a Lyons 54, another First 40 (Not a diamond), a Trip 47, a 70ft Clipper racer and a racing Farr 40.

The sea conditions on the race were described this way by Ken Read, the skipper of Comanche:

“This is a hard race. I have sailed around the world two and a half times and I thought I had seen it all but this is one hard body of water ...
This is a hard race. You guys have a hard race here. The people who have done this race 25 times, God bless them, they are the hardest people on Earth or the dumbest people on Earth, probably a combination of the two.”

Imagination, the First 47.7 that leads the First squadron is on its 3th Hobart, Black sheep (First 45) is on his 2th Hobart, Not a Diamond (First 40) his on its 2th Hobart (Both boats have been raced extensively offshore on the Australian championships), Willyama, a First 40 that is racing in 60th place is on its 4th Hobart, Pelagic magic, a First 40,7 that is racing in 65th position is on its 4th Hobart.

I really don't understand the ones that keep saying that the First are not offshore boats.

[robert sailor]

It would be interesting to get a list of the boats that retired and why..anyone know if that info is available??

[minaret]

Maybe someday some of these guys will catch on that racing has absolutely nothing to do with cruising. How likely are you to ground a boat during a Sydney-Hobart? Now compare that to how likely you are to ground a boat during a full seasons cruise in any popular cruising ground.

[jmaja]

Originally Posted by robert sailor

It would be interesting to get a list of the boats that retired and why..anyone know if that info is available??

You can find the list of the retired boats and reason for most of them at the bottom of the standings. Then you need to find the model of the boat based on its name from the list of yachts.
Standings - Rolex Sydney Hobart Yacht Race 2015
The Yachts - Rolex Sydney Hobart Yacht Race 2015

[Celestialsailor]

Originally Posted by neilpride

That X35 is one of the few using a steel or CF keel structure, I applaud that initiative, sad others don't follow something similar...

Originally Posted by neilpride

And Arcona yachts also use a steel keel grid system, SWEDEN Q.
http://www.google.es/url?sa=t&rct=j&...xk-6gLB0wvRkdA

If this is not stainless steel and having owned steel boats in my past, there would be an issue in 10 years or so. Most owners never lift a floor board to see if anything is going on.

[minaret]

Originally Posted by Celestialsailor

If this is not stainless steel and having owned steel boats in my past, there would be an issue in 10 years or so. Most owners never lift a floor board to see if anything is going on.

Couldn't agree more, this is not a great approach. The only boat I've built using this method was done in titanium; grid, keel bolts, chainplates, etc. In the bilge, a composite would be much wiser but obviously more expensive.



http://www.cruisersforum.com/forums/...-a-158536.html

[Celestialsailor]

Originally Posted by Dockhead

Indeed. 99% of sailing yachts today have bolted on keels. It's a pure question of engineering. Encapsulated keels are not inherently stronger, and indeed it was not the bolted interface which failed on Polina Star.

With all due respect sir, I disagree with that statement. I have worked on many boat in my past. You go into any boat yard and you will see signs of stress at then keel to hull attachment. Moreover and scarier, some of them have fracture cracks in the bilge. You won't see that on an encapsulated ballasted vessel.
I do like your statement on the HR's. I'm a bluecollar guy with an old HR. Very well built. The new ones?...not so much. N ice designs but I can see they are trying to cut corners.

[Polux]

Originally Posted by robert sailor

It would be interesting to get a list of the boats that retired and why..anyone know if that info is available??

Yes it is available, at least some. Many boats with rudder/steering problems, some for hitting objects but I suspect also many for pushing too hard on the rudder.

Almost all the race was upwind in nasty conditions and upwind when you want to go fast you try to put the boat on the right position towards the next wave and sometimes that, if not done with some care can generate huge pressures on the rudder.

I am sure you have experienced that, when you are on top of the wave, the wave is passing trough and you turn the boat to one side to avoid to take the next wave too much on the face, for not losing speed.

Performance boat and racing boats have very powerful and fast repose steering systems and sometimes it is difficult to notice the huge forces evolved and difficult not to push over the limit.

That is the only explanation that I can find for so many rudder problems, not necessarily broken rudders.

The other (even more) common cause was mainsail damage and after that a bit of everything, to engines not working (needed to charge batteries) to electrical problems, one broken mast, two broken forestays, two boats with minor hull damage even a boat with problems on the bowthruster

[Polux]

Originally Posted by Celestialsailor

If this is not stainless steel and having owned steel boats in my past, there would be an issue in 10 years or so. Most owners never lift a floor board to see if anything is going on.

There are many brands using that type of grid made of very tough materials, some use stainless steel but more and more are using carbon.

Almost a decade ago X-yacht stopped using a steel grid and started using a carbon grid. The steel used was subjected to several high tech treatments to prevent rusting but I agree that it will not last forever without rusting. I also pointed out already that Europeans and Americans don't have the same time frame in what regards the expectation of a sailboat's life.

[Polux]

Originally Posted by Celestialsailor

"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"
.

Funny, I think the same about sailboats but it seems to me that you don't take that approach regarding boats:

"Sailing is not a journey till the end of our days with the intention of arriving safely in a pretty and well preserved sailboat, but rather to skid in broadside on a thoroughly used up, totally worn out sailboat and loudly proclaiming: Wow - What a ride!!!!"

Sorry, I could not resist

[Celestialsailor]

Originally Posted by minaret

Couldn't agree more, this is not a great approach. The only boat I've built using this method was done in titanium; grid, keel bolts, chainplates, etc. In the bilge, a composite would be much wiser but obviously more expensive.



http://www.cruisersforum.com/forums/...-a-158536.html

Originally Posted by Polux

There are many brands using that type of grid made of very tough materials, some use stainless steel but more and more are using carbon.

Almost a decade ago X-yacht stopped using a steel grid and started using a carbon grid. The steel used was subjected to several high tech treatments to prevent rusting but I agree that it will not last forever without rusting. I also pointed out already that Europeans and Americans don't have the same time frame in what regards the expectation of a sailboat's life.

I would think Carbon Fiber to be an excellent choice. That said would have to be carefully engineered to coexist with the twisting and flexing a boat does. I know there are boats built out there with Kevlar carefully woven into a hull for strength. It's not something the home builder can slap-dash on.
One of my past boats was a Tartan Blackwatch 37 with gorgeous mahogany cabin sides. It was a 1966. The factory tried new innovated ideas for the time. On my boat, the two obvious failures were...they laminated 1/4" x 2" hot rolled steel into the laminates of the hull lay-up from the keel up close to the gunnels. Three per side to coincide with the chain plates which were SS, welded to the hot roll. Over time, water seeped into the area and began gassing out, causing a slight swelling of the chain plate area. Quite unnerving.
The second innovative idea was a gasket hull to deck joint that leaked like a sieve. I actually pried up the deck, 6 ft at a time and caulked up with slow curing 5200. Quite the ordeal.

[minaret]

Originally Posted by Celestialsailor

I would think Carbon Fiber to be an excellent choice. That said would have to be carefully engineered to coexist with the twisting and flexing a boat does. I know there are boats built out there with Kevlar carefully woven into a hull for strength. It's not something the home builder can slap-dash on.
One of my past boats was a Tartan Blackwatch 37 with gorgeous mahogany cabin sides. It was a 1966. The factory tried new innovated ideas for the time. On my boat, the two obvious failures were...they laminated 1/4" x 2" hot rolled steel into the laminates of the hull lay-up from the keel up close to the gunnels. Three per side to coincide with the chain plates which were SS, welded to the hot roll. Over time, water seeped into the area and began gassing out, causing a slight swelling of the chain plate area. Quite unnerving.
The second innovative idea was a gasket hull to deck joint that leaked like a sieve. I actually pried up the deck, 6 ft at a time and caulked up with slow curing 5200. Quite the ordeal.

Kevlar does not provide strength. It is the least stiff of all the fibers used in laminating. If you build a laminate of solid Kevlar, it will be floppy like a noodle. It is only good for point loading, ie you can't make holes in it. It's one of the more common misleading things I see printed in glossy brochures. It is also almost impossible to make repairs on. Not a good thing. The vast majority of boats I have worked on with Kevlar in the layup, it has been strictly a sales gimmick.