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Discussion Starter #1 (Edited)
My wife and I are the happy owners of a 2000 Hunter 340. Boat surveyed almost flawlessly a year ago. Had a good season, saw a little rough weather on the Chesapeake and spent the winter in the water. Come the spring, we noticed water kept appearing in the bilge. We'd dry it out, it would come back.

Over a couple months, we progressively eliminated sources until we finally began to realize the water was coming from the #4 and #5 aft most keel bolts. Out of an abundance of caution, we hauled the boat, brought the surveyor out and revealed that we likely had a crack in the keel bedding that was letting water in via the keel joint. Recommended repairs was to expose the joint and fill it. Most yards stated the only sure way to repair such an issue was to drop and rebed the keel.

After much hand-wringing, the need for safety won out. We contracted for a yard in Annapolis to do the work and got the boat in the keel stand. They pulled the keel nuts and backing plates and we saw water in the tunnels. That cinched it.

Hunter owners out there, do you ever wonder why you rarely hear about issues with Hunter keels?

Here's the reason:

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That's air. Air from the gap from the saw required to cut away the keel joint to drop the keel. Air across 90% of the joint save for the first 3 keel bolt holes. That is all that is holding 4600+ pounds of lead in the air still attached to the boat.

All courtesy of Hunter's preferred bedding compound for keels: Epoxy.

I learned a lot that day. The main thing being that Hunters don't have keel issues because the bond is so strong it takes a very hard grounding to damage them. Even the factory was surprised to hear a 340 was getting the keel done.

For some reason, lots of builders are putting keels on with epoxy nowadays. It makes sense from a maintenance standpoint. Trouble-free when it works and beyond incredibly strong. The keel bolts are an afterthought. You don't need them. I have 5 keel bolts, 4 of them 1 1/4" monsters and in an epoxy joint, they are superfluous. All five nuts were off and the keel was hanging on the boat from three plugs of epoxy that had formed around the forward 3 keel bolt studs.

But epoxy creates stiffness along a joint of dissimilar materials that can and does flex. Hence why you're supposed to bed with something flexible to allow for that motion. As long as it holds up it will be fine.

But, as my experience shows, once a little fatigue happens or the joint flexes beyond the tensile strength of the epoxy, it doesn't bend; it cracks. That's what we think happened in our boat. That probably combined with a day at the factory where not enough epoxy was put on the day my keel was bedded on.

And when you need to fix it, here's where you wind up:

100_1110.jpg

Enjoy that view (or cringe in horror) and see what happens when epoxy as a joint compound fails you.

The end result, though, was a keel rebed that was better than new. The keel stub was repaired to perfection, the keel was rebedded with 3M 4200 and allowed the keel bolts to be actual bolts to hold the keel on and faired so beautifully you can't find the joint even if you knew where to look.

Hunter has apparently been doing this forever. And with few problems to their credit. Until you have one like mine. And so are a lot of other makers which leads me to wonder where they will be once sailing stresses take their toll on what is a butt joint to the bottom of their hulls rather than against a dedicated sump like on my boat.

But feel free to share this little tidbit with friends and fellow surveyors. Even our surveyor never knew this about Hunters.

I have plenty of pictures of this experience if anyone is curious about the process of dropping an epoxy bedded keel and putting it back on. The end result for us is peace of mind.

Matt
 

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Many builders use an epoxy based keel putty with an elastomeric around the bolts. Hunter is not unique in this regard. Catalina & Sabre are two that spring to mind....

Course the keel sump & stub, while thick, is often very poorly wetted out so when the keel does need to be dropped there may be a lot of repair work re-laminating the lack of factory wet out..



And then there is always the possibility you lose the entire sump..;)





The strength of the keel bolts or keel to sump/stub epoxy is irrelevant if the hull can't hold onto the sump...
 

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Many builders use an epoxy based keel putty with an elastomeric around the bolts. Hunter is not unique in this regard. Catalina & Sabre are two that spring to mind....

Course the keel sump & stub, while thick, is often very poorly wetted out so when the keel does need to be dropped there may be a lot of repair work re-laminating the lack of factory wet out..



And then there is always the possibility you lose the entire sump..;)





The strength of the keel bolts or keel to sump/stub epoxy is irrelevant if the hull can't hold onto the sump...
Is that the super shallow draft version? I hear that is an expensive option!

To me it does seem to be strong, but only if there are no air gaps. But of course it is not exactly making for easy maintenance. Seems to me to be a more of a budget cutting measure as I am sure the epoxy that they buy by the tanker full is cheaper than 3M 5200, but is not made for any kind of repairs or maintenance. Kind of like the new "sealed for life" transmissions. Sure fine for the first owner, but not so much so for the second who has to have it rebuilt because they made it so you could not have the fluid changed as part of the scheduled maintenance.
 

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Discussion Starter #6
Many builders use an epoxy based keel putty with an elastomeric around the bolts. Hunter is not unique in this regard. Catalina & Sabre are two that spring to mind....

Course the keel sump & stub, while thick, is often very poorly wetted out so when the keel does need to be dropped there may be a lot of repair work re-laminating the lack of factory wet out..

The strength of the keel bolts or keel to sump/stub epoxy is irrelevant if the hull can't hold onto the sump...
Can't do much with bad engineering or a thin layup. O'Day 30s are another boat with a thin layup at the sump.

Here's my sump:

100_1115.jpg
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100_1125.jpg

The holes are the #2 and #3 bolt holes and the hardened epoxy that flowed into them and had to be drilled out is clearly visible. The layup here is a shade over 1 1/2" thick. The layup color is very consistent throughout which tells me they did a good job at wetting it out.

The hacked up stub from the saw work was rebuilt with a bed of epoxy to create a perfect mating surface for the keel. The keel was put back on with the weight of the boat on it and allowed to cure to make sure there were absolutely no gaps. Then the boat was lifted off and the keel was then rebedded and reattached to the hull.

100_1128.jpg
100_1132.jpg

If the sump was weak, there'd be evidence of it by now due to the original bond flexing the sump laminate. What little I've found about H340s and their keels indicate the joint is quite strong. I've only found one other report of a keel drop on an H340 and it was a boat in Maine that went hard aground. Sliced the front of the bulb off. The joint didn't crack or open up. They dropped the keel (alas, didn't report the bonding material in the details), recast the lost lead and put it back on.

I'm not terribly worried about the thickness of my sump as the surveyor nor the folks I contracted for the work expressed any issues or concerns. Just the opposite. They were cursing the toughness of the boat in getting this work done.

Matt
 

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Discussion Starter #8
So, in all this, I'm still wondering what caused the damage in the first place. If it was cracked and leaking toward the aft end of the keel - that sounds like a pretty good grounding.
We exposed the joint and it appeared to be a hairline crack towards the aft on the port side. Barely visible. There is no evidence of the boat ever having gone aground, we've never been aground since we bought it and the boat has spent its entire life on the Chesapeake Bay. Not impossible to ground and do damage but one of the safest places in the world to do it.

I've seen keels with grounding damage. No scrapes, no dents, no chunks removed, nothing on ours. Only evidence of an issue on the keel was the cracking fairing compound and that is a common problem on externally ballasted boats. Inspection found no evidence of any keel damage at all.

Our best speculation is given the thinness of the keel profile at the aft is more prone to flex and there isn't a lot of surface area there to bond to. And after putting the keel back on the long keel studs made it hard to get good torque on the nuts. Probably a combination of the long bolts, thin keel and perhaps a light amount of epoxy contributed. We sailed the boat in heavy conditions during a day race and we think that it started the crack to open just enough as the keel flexed in 30 knots of wind and short 4-6 foot chop.

The amount of water was negligible. Perhaps a paper towel's worth a day after we splashed following our two weeks on the hard for inspection. I checked the boat twice a day for the six weeks leading up to the repair date. Even the surveyor said it was a long term problem and recommended against repair unless we planned to keep the boat a long time (more than 5 years). Just live with it, sell it and make it someone else's problem.

This we obvious did not do. There was no corrosion on the studs and virtually no delamination in the glass in rearmost stud tunnels. So we caught it very early before it had a chance to damage the studs or wreck the rear sump laminate. Crevice corrosion on the bottom of the #4 backing plate but that is not uncommon given the shape of the sump in this area.

As I said, speculation at best. Since the repair, the boat is back to being bone dry in the bilge.

Matt
 

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Discussion Starter #9
So why did you use 3M 4200 instead of 3M 5200 for re-bedding the keel?
On the advice of people far more experienced that I. We considered 5200 but there is ever another problem with the keel, getting it off is as bad, if not worse, than an epoxy bed. 5200 gives the flex but is still a cast-iron bastard to get off if something goes wrong.

Since the bolts are there to provide the mechanical attachment to the boat and the bolts on the 340 are 4 1 1/4" and 1 1", they had plenty of strength. 3M 4200 is an adhesive and is still insanely strong.

So we accepted it as a compromise to retain a lot of the original bond, allow the keel to flex like it is supposed to and make it actually possible to drop the keel in the event damage is done. And not at the cost of two solid days in the slings and damage to the keel stub in getting it off. 4200 will actually separate.

They were recommending a straight bedding compound like they do on race boats. 4200 was the middle ground from a 5200/epoxy bed.

Matt
 

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On the advice of people far more experienced that I. We considered 5200 but there is ever another problem with the keel, getting it off is as bad, if not worse, than an epoxy bed... 3M 4200 is an adhesive and is still insanely strong... 4200 was the middle ground from a 5200/epoxy bed.

Matt
You really need to do some more research Matt. You are throwing statements around that are not correct. You should not rely on the yard "experts", who may not know any better than you do. In addition, the yard experts may not have your best interests in mind. Some yards do things to generate continuing business for themselves.

You are equating 5200 with epoxy, which is an erroneous comparison. The tensile strength of epoxy is more than 10 times stronger than the tensile strength 3M 5200.

The tensile strength of 5200 is 705 p.s.i. http://multimedia.3m.com/mws/mediawebserver?mwsId=SSSSSuH8gc7nZxtU48_eoYtvevUqe17zHvTSevTSeSSSSSS--&fn=Sealant%205200.pdf(twice the strength of 4200).

The tensile strength of epoxy resin is 10,500 p.s.i. (aeromarine plastics brand http://www.aeromarineproducts.com/pages/pdf/30021-tds.pdf)

3M 4200 is designed to cure faster, at a loss of some strength compared to 3M 5200. There is no difference in flexibility with 3M 5200.

A keel should not be bedded with epoxy, period. 3M 5200 would be the correct adhesive for bedding the keel and would allow the keel to drop after the bolts are loosened.
 

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Matt-
FWIW "Hunter" went out of business about a year ago. The new owners, who bought the assets, may or may not be building the same way.


5200 requires no mixing but requires a fairly long cure time, days. Eventually it does get quite hard but I suspect it still is more flexible than many epoxies. Epoxy has to be mixed properly and typically cures in hours, or overnight. So besides price, there could be good reasons to use one or the other in the larger manufacturing process.
 

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...FWIW "Hunter" went out of business about a year ago. The new owners, who bought the assets, may or may not be building the same way...
IMO the words that you chose are misleading.

Hunter did not go out of business. The parent company Morgan Industries went bankrupt and sold the Hunter division to David Marlow right at the deadline. While technically true that he "bought the assets," your choice of those words implies that the company was somehow dismantled, which is not true. David bought the division intact, and when I spoke to him last October he was still operating out of the same factory with the management team intact. He did acquire other assets like the Luhrs factory property, so he could move some production there.

With the same management and the same factory site, I would be surprised if Marlow-Hunter changed something as fundamental as how they bed their keels. Do you have any facts to back this up? Do you know of other major changes since October that I'm not aware of?
 

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Five, then I've been mislead. A member of one of the ofrums said they went by the Hunter yard and it was padlocked and closed. This was followed by news that they had filed for bankruptcy and subsequently, the new owners bought the assets of the company and were re-opening it again, with no mention that they were also buying the liabilities, specifically, no mention that they would honor existing contracts or warranties.

If that's incorrect, then that's incorrect. As you say you've actually spoken to the new owner, it would seem that you've got better information.

Have you seen any specific citation that the new company IS honoring past liabilities, including purchase contracts for existing hulls, and warranty expenses? It would seem that they should have been very proud to announce that, if that were the case.

I missed the memo?
 

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You really need to do some more research Matt. You are throwing statements around that are not correct.
Hello pot....;)


A keel should not be bedded with epoxy, period.
Lots of keels are and have been bedded with polyester resin or epoxy products by some very high end builders as well as many production builders. It has been done like this for years. Sabre was doing this all the way back to the original Sabre 28's using a "special mix" polyester resin. Even the last of the Sabre's built used epoxy set keels. The absolute last Sabre sailboat built t-boned a solid granite ledge here three weeks ago and survived to sail the race she was here for.... Catalina uses an epoxy mix as well and has been for many years. They have pretty much eliminated the Catalina smile...

There are many ways to set keels and a polyurethane is but one method but is by no means the only method. I have watched keels be set by Hinckley, Morris, Lyman Morse, Hodgdon Yachts, Sabre and numerous local yards.. They all use different methods and product. When I reset my Catalina keel I used a polyurethane. Our CS has been almost around the world and the keel is set in some sort of polyester like putty, not a polyurethane. Bone dry, no leaks, no hairline cracks, no smiles.....




3M 5200 would be the correct adhesive for bedding the keel and would allow the keel to drop after the bolts are loosened.
A properly bedded keel with 5200 WILL NOT drop once the nuts are pulled. First hand experience, oak wedges, Sawzall etc. is how I know....
 

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Five, then I've been mislead. A member of one of the ofrums said they went by the Hunter yard and it was padlocked and closed. This was followed by news that they had filed for bankruptcy and subsequently, the new owners bought the assets of the company and were re-opening it again, with no mention that they were also buying the liabilities, specifically, no mention that they would honor existing contracts or warranties.

If that's incorrect, then that's incorrect. As you say you've actually spoken to the new owner, it would seem that you've got better information.

Have you seen any specific citation that the new company IS honoring past liabilities, including purchase contracts for existing hulls, and warranty expenses? It would seem that they should have been very proud to announce that, if that were the case.

I missed the memo?
I don't think you missed any memo.

When I said that he bought the company intact, I meant he kept key personnel, and is operating the same mfg plant, and thus probably using the same production techniques. If you define "intact" as acquiring all assets plus all liabilities, then I doubt that's what happened, because that's not how bankruptcy works. I'm not a lawyer, but I've been around business enough to know that the whole purpose of bankruptcy liquidation is to separate the assets from the liabilities, sell the assets, and distribute the sale proceeds to the creditors (often pennies on the dollar). Without separating the liabilities out, there would be no buyers. If there were buyers willing to buy the company with the liabilities, then the company would be sold without going through bankruptcy.

So in the strictly legal sense (as this non-lawyer views it), Marlow probably acquired the assets and shed the liabilities. And, sorry for the owners, but that probably means he is under no legal obligation to honor warranties of the pre-bankruptcy entity. Warranties are almost never honored in bankruptcy unless you have a specific monetary claim, and then you file your claim as a creditor and wait in line to get your pennies on the dollar. The auto bailout was an exception, but that was the extraordinary case of the US Govt providing the debtor-in-possession financing, which means they could require (and provide the money for) continuation of the warranties for cars sold before the bankruptcy.

This is all speculative on my part, since I did not get a memo either. If someone with specific knowledge of Marlow-Hunter's business situation wants to correct me, that's great.

As for the padlocked plant, I read somewhere that they had gone to a 4-day workweek during the downturn, so perhaps your friend visited them during a hiatus in production.
 

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Discussion Starter #16 (Edited)
You really need to do some more research Matt. You are throwing statements around that are not correct. You should not rely on the yard "experts", who may not know any better than you do. In addition, the yard experts may not have your best interests in mind. Some yards do things to generate continuing business for themselves.

You are equating 5200 with epoxy, which is an erroneous comparison. The tensile strength of epoxy is more than 10 times stronger than the tensile strength 3M 5200.

3M 4200 is designed to cure faster, at a loss of some strength compared to 3M 5200. There is no difference in flexibility with 3M 5200.

A keel should not be bedded with epoxy, period. 3M 5200 would be the correct adhesive for bedding the keel and would allow the keel to drop after the bolts are loosened.
Perhaps and I never claimed expertise. My wife and I agonized over the decision on what to put the keel back on with. The problem with 5200 is it is meant to be a permanent adhesive. Yes, it is more flexible than epoxy but it still forms a bond that is not meant to be separated.

Originally, Hunter told us this was a 5200 bond. And the yard dogs were cursing at that prospect as it was as it was going to involve chisels, knives and cursing. Yes, the keel will eventually drop with 5200 once you "persuade" enough of it apart from the surfaces it is bonding but it is going to take laminate away with it. That is what they had prepared us for and the big unknown in the job was the amount of stub that was going to come off with the keel.

The yard guys were talking us out of the keel drop right up until we found the water in the keel bolt tunnels and black organic mess that had gathered under the rear backing plates. That cinched the guess that it was, in fact, water intrusion from the keel and not another source. They weren't blindly accepting our (considerable) amount of money because we said we needed to drop the keel. Trust me, we did not want to do it.

They were quite stunned to see a white joint line rather than a bead from a 5200 bed. A bit of a blessing in the sense having to saw the keel off minimized the amount of damage to the stub. There was no guessing how much 5200 was going to remove once the keel let go. And we were told there was a possibility the damage could ruin the boat.

The 5200/4200 decision hinged on strength and the possibility of being back in the yard again if something else went wrong. A hard grounding, another leak, who knows? If we weren't sacrificing much strength between 4200 and 5200 and 4200 won't rip off fiberglass in the event we need to do this again, it was a clear winner.

At the end of the day, we have to be comfortable with the quality of the repair. We've been in regular contact with the yard and will be having things checked again at the end of the season when the boat comes out for how the keel joint is doing on the outside and checking up on the torque on the bolts.

Just wanted to pass along the little tidbit on how Hunter keels are put on so others can be forearmed with knowledge should they find a boat with a keel issue.

Matt
 

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"perhaps your friend visited them "
I never mentioned a friend. or an acquaintance. I said someone on another forum.
A friend is someone who will bring you bail money, or any other unlikely request, and ask questions later. An acquaintance is someone you'd be reluctant to call for the same reason as your friend. Some guy online? Could be a dog (old joke) for all you know on the internet.
As you say, things change during a bankruptcy sale. The old company and the old ways didn't make a sufficient profit. The new company will make changes to ensure profits. And typically, that means, yes, they will do things differently. If the old company riveted on the wings (like Boeing) or welded on the wings, the new one might glue the wings on. As they are on some modern combat aircraft, even if those are also from Boeing.
And with some stuff today, I see glue used in big plants and multiple expensive screws used in smaller plants, where they don't know what glue is. Yet. Slave labor is cheaper than glue.
No way to tell unless you call Mr. Marlow and ask, huh?
 

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Discussion Starter #18
Matt-
FWIW "Hunter" went out of business about a year ago. The new owners, who bought the assets, may or may not be building the same way.

5200 requires no mixing but requires a fairly long cure time, days. Eventually it does get quite hard but I suspect it still is more flexible than many epoxies. Epoxy has to be mixed properly and typically cures in hours, or overnight. So besides price, there could be good reasons to use one or the other in the larger manufacturing process.
My boat is a 2000, so it is well pre-bankruptcy. And one of the fellows who worked on this called the factory and had a nice, long conversation on this. The individual they spoke to was a carryover from Hunter to Marlow-Hunter. They pretty much told him every single Hunter keel was put on with epoxy.

Which explains a lot when you get to Googling keel issues and Hunters. Save for a couple of Hunter models which seem to be prone to loosening keels, you virtually never hear of an issue with their keels. With the work behind us, we know now there was NO CHANCE that keel was ever going to fall off by itself. EVER. But before, that was our fear. And logically so.

Water coming up into your bilge? That's a polite way of saying your boat is sinking slowly. Water comes top down, not bottom up. And can you blame such paranoia about an external keel developing a problem and coming free in the wake of Cheeki Rafiki? You have to have confidence in your boat. A keel working free and falling off in the open ocean I think is the darkest nightmares of every sailor everywhere.

Keep in mind I am not angry or disappointed in Hunter at all. The cost definitely sucked. But it is life with a sailboat. As I counsel friends, "If you like having money in the bank, don't buy a boat.". Another Hunter is on our short list of "final" sailboats to go cruising on many years from now. I'm not unhappy with our H340 at all. In fact, I'd argue she came back from the yard after the repair a better boat overall.

Matt
 

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"They pretty much told him every single Hunter keel was put on with epoxy. "
Heheh. Cheeki Rafiki? Maybe you didn't hear about, what was it, Thursday's Child? A boat custom built for the head of Hunter back around the late 80's, that lost its keel very soon after launching. One might suspect that event inspired someone to use epoxy on the later boats. Ya'think?

As to 4300/vs/5200 and peeling off laminates, that sounds like someone doesn't quite have it right. If 4200 and 5200 have "almost the same" bond strength, they will remain bonded to a laminate, or not, in the same way. Given that the strength of laminates will also vary quite a bit, there would have to be a significant difference between the bond strength (4200/5200) and the 4200 would have to be significantly weaker in order to ensure it failed to bond, and released from the laminate. I don't know, I'm not looking those up. Just saying, the (non)numbers don't add up unless there is some significant difference.

If you have, say, a six by 36 inch area to bond, that's only 216 square inches, but if the bond strength is 700# per square inch, that's still enough to keep a seventy-five ton keel attached. Assuming the laminate can hold up to that.(G)
 

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The notion that the keel was held in place by epoxy, and that the keel bolts are essentially superfluous, is very misleading. The epoxy is there to keep the water out, period. Epoxy is very strong stuff, but it is also prone to crack propagation (as you have apparently found out). Therefore, the material tensile strength (e.g., the value given in an earlier post in this thread) may seem pretty impressive, but that is determined using a very small homogeneous specimen under optimal conditions. One little flaw (and there are always flaws under real world conditions) and catastrophic failure is inevitable. Steel, bronze, and iron are much more forgiving, which is one reason they are used in applications with high tensile loads (like keel bolts). I can pretty much guarantee that without bolts your keel would have fallen off a long time ago.
 
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