Sudden Attraction to Hunters

[neilpride]

Originally Posted by Kenomac

Just to be clear for other Hunter owners, our 450 keel did not come loose as a result of the boat resting on it's keel, owner neglect or misuse as Sailorboy1 suggests. It came loose due to a faulty keel joint, and poorly engineered honeycomb lower section design. The lower portion, normally solid lead on most sailboats, was a honeycomb design that Hunter filled with sprayed-in expanding foam insulation. When the keel joint became compromised due to not enough bonding surface area, the foam/voids held in the seawater like a giant sponge and rusted the stainless steel keel bolts.

The yard which made the repairs (KKMI) removed the foam and filled the large voids so that the problem would not repeat itself.

Sailorboy1 has had this explained to him many times, I don't know why he keeps repeating himself about the boat resting on it's keel stuff.

My reason for posting this information is not to "bash Hunters" as he claims, it's to alert other Hunter owners of the potential problem, so that it can be remedied prior to it creating a catastrophic failure. To simply ignore the problem as some would prefer you do... is foolish.

Following the repair, we went on to enjoy our Hunter for two more years in Southern California, and I assume the new owner is doing the same.

Im trying to figúrate WTF is a honeycomb lower keel section?? do you mean the lower lead keel section is filled with foam? Is the keel hollow or filled with lead?

Regarding the boat restin on the keel and with the result of a loose keel or damage i, well depend how hard is the bottom, soft mud is not a problem, even sand is not a problem, boats are designed to rest on the keel, in the hard, in a tide, or aground, racing boats are haul out several times during a year and resting on their own keels, kind of BS argument, in Florida in some Canals you can get your boat 2 times aground in the slip per day and in EU same , my previous boat spend 4 years docked in a dock in Florida up and down up and down, deep draft touching the mud every day , no problems at all....

[Kenomac]

Originally Posted by neilpride

Im trying to figúrate WTF is a honeycomb lower keel section?? do you mean the lower lead keel section is filled with foam? Is the keel hollow or filled with lead?

Pictures of the Hunter 450 keel undergoing removal of the waterlogged foam and honeycomb voids during repair at KKMI:

[Kenomac]

Originally Posted by hjv

How much did the repair cost? Or putting it another way. How much would such a condition deduct from the price of a used boat?

The repairs cost over $10,000. I don't know the exact amount, because it was paid for by the seller and involved the removal of the rig. It would not be fair to Hunter owners to assume every Hunter or even most Hunters have this problem. This particular model, the 450 has the keel to hull issue that we experienced. Others may also be constructed in the same manner... I don't know. Hunter Marine would not cooperate in any way or even return phone calls when we asked questions back in 2009, even though the company was not being asked to pay for any of the repair.

Not all Hunters will have this problem, but if you see weeping along the keel to hull joint which continues for hours following a haul out, the problem needs to be investigated... especially if you have salt water in the bilge.

[neilpride]

Okey thx for the pic, i think i see it before in a old hunter topic if i remember well, but never suspect is your boat, anyway i dont get the point why Hunter choose to make such a weird thing in the keel , but i see you still have the bolts intact, the wet foam with a fail joint is a wonderfull scenario to get corroded bolts fasttttt!!!

[Kenomac]

Originally Posted by neilpride

Okey thx for the pic, [edit] i dont get the point why Hunter choose to make such a weird thing in the keel , but i see you still have the bolts intact, the wet foam with a fail joint is a wonderfull scenario to get corroded bolts fasttttt!!!

You're very welcome and I Agree.... but try to explain this to a Hunterfanboy.

The yard replaced one completely rusted keel bolt and filled the voids with epoxy filler prior to the proper reinstallation of the keel. Now there are two large flat surfaces to bond using a caulking material and nowhere for the salt water to collect. Our former boat now has a proper keel joint.

[hjv]

Originally Posted by Kenomac

The repairs cost over $10,000. I don't know the exact amount, because it was paid for by the seller and involved the removal of the rig. It would not be fair to Hunter owners to assume every Hunter or even most Hunters have this problem. This particular model, the 450 has the keel to hull issue that we experienced. Others may also be constructed in the same manner... I don't know. Hunter Marine would not cooperate in any way or even return phone calls when we asked questions back in 2009, even though the company was not being asked to pay for any of the repair.

Not all Hunters will have this problem, but if you see weeping along the keel to hull joint which continues for hours following a haul out, the problem needs to be investigated... especially if you have salt water in the bilge.

Ansolutely a point to add to the list of extra investigation points for a survey for Hunter 450 and other boats with similar keel solution. This will help other sailors to make more informed and better decicions regarding the condition of a prospective Hunter. You've been very helpful. Thank you for sharing.

[S/V Illusion]

Originally Posted by hjv

Ansolutely a point to add to the list of extra investigation points for a survey for Hunter 450 and other boats with similar keel solution. This will help other sailors to make more informed and better decicions regarding the condition of a prospective Hunter. You've been very helpful. Thank you for sharing.

More informed?
Having once owned a Hunter, I was interested in the allegation some of their keel designs present a structural failure potential so I contacted the design architect who worked on my present boat as an objective source.

What he referred me to was the following:

DOI: 10.1016/j.engfailanal.2012.06.002
Abstract

Several cracks were detected in the internal structure of the bilge keels used to enhance the transverse stability of ships, as well as on the connection of these to the hull and in some regions of the plating edges of the bilge keels. These cracks compromised the watertight integrity of the bilge keels and, in the long run, could also jeopardize the integrity of the hull.
A failure analysis of the structural damages detected was carried out, in order to identify the causes of failure and to propose improvements that could avoid them. Several stress concentration regions were identified in the structure studied, which coincided with the critical areas where the structural failures were found. The influence of the internal reinforcements of the hull (stiffeners) in the increased levels of stress induced in the welded joints of the bilge keels to the hull was also assessed.
Improved design geometry for the bilge keel internal structure was proposed, taking into account the longitudinal and transversal structural performance of the bilge keels.

----------------------------------------------------------------------------------

One can refer to the complete document if interested.

The short version being the internal keel structure is stronger if designed to accommodate adjacent high stress areas in the bilge structure. He assured me it is a common practice among high-end boat builders including the keel on my boat which hasn't fallen off yet.

I guess if it was on a Hunter, that would make a difference to certain people.

[Kenomac]

How can the Hunter keel be considered a "bilge keel" when all the voids/cavities are filled with expanding foam insulation, and there isn't any direct connection to the shallow bilge that's part of the hull other than the keel bolt holes? The 450 has a bilge that's only 18 inches deep and will only hold a few gallons... maybe three at most. What you see in the Hunter keel repair pictures is not the Hunter 450's actual bilge.

[Opie91]

Originally Posted by Kenomac

How can the Hunter keel be considered a "bilge keel" when all the voids/cavities are filled with expanding foam insulation, and there isn't any direct connection to the shallow bilge that's part of the hull other than the keel bolt holes? The 450 has a bilge that's only 18 inches deep and will only hold a few gallons... maybe three at most. What you see in the Hunter keel repair pictures is not the Hunter 450's actual bilge.

Sounds like Hunter wanted more surface area on the keel than a solid lead keel would give them. Too bad they decided to cheap out with the expandable foam.

I am having a hard time understanding why they would fill up that area with foam to begin with.

[DoubleWhisky]

Originally Posted by Opie91

Sounds like Hunter wanted more surface area on the keel than a solid lead keel would give them. Too bad they decided to cheap out with the expandable foam.

I am having a hard time understanding why they would fill up that area with foam to begin with.

I just think You answered Your question Yourself

Cheers,

Tomasz

[Opie91]

I know, but it seems that it would be better to leave the cavity empty instead of filling it with foam.

[S/V Illusion]

Originally Posted by Opie91

Sounds like Hunter wanted more surface area on the keel than a solid lead keel would give them. Too bad they decided to cheap out with the expandable foam.

I am having a hard time understanding why they would fill up that area with foam to begin with.

My understanding, after discussing this with the naval architect I mentioned previously, is that the design creates greater strength and reduces potential of stress fractures. You can fill the voids with bumblebee fur and it wouldn't make any difference except, of course,to the guy who likes to criticize that which he doesn't like.

[a64pilot]

Originally Posted by S/V Illusion

My understanding, after discussing this with the naval architect I mentioned previously, is that the design creates greater strength and reduces potential of stress fractures. You can fill the voids with bumblebee fur and it wouldn't make any difference except, of course,to the guy who likes to criticize that which he doesn't like.

As long as the seal is intact, I'd say you are correct, it's if the seal is broken that the problem occurs. I wonder why fill it with anything? Foam can't have been considered structural, filling with epoxy though would add structure and a whole lot more sealing surface. Myself I'd rather have the extra margin the epoxy would give me.

My neighbor at the Marina are liveaboards in a 38 Lagoon I believe, last boat they had was a Hunter 450, they ran her aground in sand off of Savannah and by the time they could get her off the wave action had broken every stringer in the bottom of the boat in the keel joint area. I don't know how long she was there, nor how big the waves were, boat was totaled.
Interestingly, they speak well of the boat.

[DoubleWhisky]

Originally Posted by S/V Illusion

My understanding, after discussing this with the naval architect I mentioned previously, is that the design creates greater strength and reduces potential of stress fractures.

If You have a second look at the photos, You can find it is not true for the keel in question.

The bolt positioning is narrow still and bolt positioning is what counts.
The reason for this particular design was probably keep a centre of gravity lower, without going for complications of bulbous keel - expensive to design and expensive to manufacture. Nothing wrong about it, there are a lot of such a keels around.
Shame is, this broad keel was not used to put the bolts further apart for added strength and the void was not properly sealed.

Cheers,

Tomasz

[smackdaddy]

Sailorboy/Don - I just finished reading the entire thread. Very, very informative. Thanks for all the updates.

Like you, I was very wary of the Hunters after hanging around the various sailing forums for a while. But, also like you, I eventually realized that the bashing (Hunter or any other production boat) was seriously hysterical and increasingly silly. So I bought a used Hunter Legend 40 - and love it.

You have probably seen the "Production Boats and the Limits" thread I started over on SN that now has almost 1K posts and 120K+ views. It's more general than this thread in the sense that it covers all production boats: B/H/C/J/B, etc. - but, like this thread, it's a great resource for people looking to buy a boat.

As I've said there, the Hunter debate was over when S/V Sequitur (a Hunter 49) very comfortably endured an F10-11 in the Southern Ocean after rounding Cape Horn:



Sequitur

And then you have guys like Mark and others doing what many forumers say shouldn't be possible. So why this debate continues to rage is beyond me.

These modern production boats are built to handle typical "blue water" conditions. Period. No freakin' way would I ever buy an older "blue water boat" over a newer (even used) production boat...even for crossing oceans.

Hal Roth in his "Handing Storms at Sea" put these kinds of debates in perfect perspective for me. If you want to drag around your slow, stuffy, old bluewater boat your entire cruising life for that less than 1% of a storm that will make you feel like your boat choice was worth it...go for it. I'd rather enjoy the other 99% - AND - be okay in that same storm.

Now as for people being outraged that a Hunter can have problems after being grounded and pounding for an extended period on its side or on its keel - I just have to concluded that they don't really understand boats very well.

Anyway, great thread. Thanks dude.