Island Packet 32 hull oil canning?

[Handsoff]

Hi,
My boat was surveyed and the surveyor stated the hull was oil canning which he had never seen before. See attached photos
My questions are:
1. How can I confirm this is happening?
2 If it is happening, how can I fix this?

Thanks in advance
Marshall

[a64pilot]

Pull the boat and have it inspected, or do it yourself.
If it’s really oil canning then you can make it move with firm pressure with your hands, maybe throw a shoulder into it. Even if your an abnormally strong person, you should not be able to flex an IP’s hull.
Never heard of this in an IP
Fix is either ignore it, or have a stringer glassed into the inside of the hull that pushes out right at the spot where it oil cans.
The ones I have seen were factory defects, came that way new. Supposedly pulling the hull too early while the glass is still “Green” is one cause I have heard.
I have never heard of a hull developing an oil canning spot later in its life, unless of course it’s had some kind of hard impact from something, fell off of stands or similar?

Note, I’m no hull expert, surveyor or any other professional, so get a pro’s opinion of course.
Wish Minaret was still around, anybody know where he went?

[toddster8]

Left on a poorly-placed stand for too long.

[kapnd]

I’ve seen literally hundreds of boats whose hulls would not withstand point pressure, as in a poorly placed stand, but were fine in the water, or on properly placed stands.
The spot on your hull is likely in poor shape because of improper preparation of the area where the stand was while the rest of the hull was prepped and painted.
Many times, those spots get a very hurried coat of paint with little prep.
Oil canning to me indicates that the hull is moving while underway, did your surveyor note this underway or on the hard?
Even some movement while underway is quite common, in fact, flexibility in plastics is one of their great strengths, known as resiliency. Of course, there are limits...
Note how carefully racing boats are handled, most of them are eggshell thin, and lifting them is an engineering specification, yet they are tough enough to fly over the water at speeds that make me cringe!

[Handsoff]

Thanks everyone for your replies. I've investigated a little further and am confident that the boat was not improperly placed on a stand during haul out.

I know this problem was not there last year when I hauled the boat out for a bottom paint. And everyone says IP does not have this problem.

Therefore, mea culpa. I think I did it. Here's how. The boat is on the west coast of Florida. Very shallow water. Coming back from the Dry Tortugas on my first solo, overnight passage, I ran aground. It was not a hard grounding and the bottom was sand. BUT, when I rocked the boat back and forth to dislodge it (which was successful), I probably hit a rock. I did not hear anything or feel anything, but its the only explanation I can come up with.

Anyhow, I am hoping I can repair this problem. Do you folks think it can be repaired and what would be the best approach - fill in the depression, cut out the depression and re-glass?

Comments, most appreciated.

Thanks again
Marshall

[billknny]

Originally Posted by Handsoff

Thanks everyone for your replies. I've investigated a little further and am confident that the boat was not improperly placed on a stand during haul out.

I know this problem was not there last year when I hauled the boat out for a bottom paint. And everyone says IP does not have this problem.

Therefore, mea culpa. I think I did it. Here's how. The boat is on the west coast of Florida. Very shallow water. Coming back from the Dry Tortugas on my first solo, overnight passage, I ran aground. It was not a hard grounding and the bottom was sand. BUT, when I rocked the boat back and forth to dislodge it (which was successful), I probably hit a rock. I did not hear anything or feel anything, but its the only explanation I can come up with.

Anyhow, I am hoping I can repair this problem. Do you folks think it can be repaired and what would be the best approach - fill in the depression, cut out the depression and re-glass?

Comments, most appreciated.

Thanks again
Marshall

It certainly can be fixed, but... Do NOT just fill the outside "dent".

It looks to me like you have significant delamination from an impact at that spot--although it is VERY hard to tell from a photo.

A sounding hammer will tell you everything you need to know. If it is delaminated, you'll hear a fairly dramatic difference between the dent ("Thud") and the surrounding hull ("Dink")

Did the surveyor do hammer testing? if yes, was there a comment about this spot other than "oil canning"? If it was not sounded, I'd seriously worry about the competence of that person surveying fiberglass boats!

[a64pilot]

You need either an expert surveyor, or an expert fiberglass guy.
I don’t believe you could have done it in a grounding, but I cannot come up with a way in which it could have been done.
I’m at a loss.
A sounding hammer ought to tell if there is delamination, an ultrasound certainly would.
Try calling the factory, perhaps they have an idea?

Stand wise an older IP will sit on its keel all by itself, of course it would likely fall over first wind so you need stands, but they really shouldn’t be holding much weight, and due partially to its shape an IP hull is a lot like an egg, which is to say it’s very stiff.
It’s not particularly thick though, but well laid up without much resin.

First sailboat I bought failed survey, it’s hull had a dimple exactly like this, and you could move it with hand pressure, that is what oil canning is, movement, it’s not a dimple, it’s flexing.
Anyway on that boat it was a well known problem, the users group told me exactly what to look for, and the fix was well known too, I was ready to haggle with the oil canning, but the wet deck scared me off.

Point being was it was a manufacturers defect, from manufacturing, it came that way, it wasn’t damaged etc. I have never heard of an IP having a dimple like that, but am very interested in what you find out.

There is an IP users group, it’s run by a Retired School Teacher I think, that either used to or sells IP’s. It’s not as useful in my opinion as this site, but it can’t hurt to post over there and ask.

[CaptRory]

As another IP owner, I don't understand it either, never seen or heard of such a thing. These things are built like tanks. I cannot tell you how many times I have run aground in the Florida sand. I have even pounded on sand bar in surf once for hours, and all that happened was some seperated tabbing. I would not rest until it was accounted for. Where on the west coast are you. If you are near St. Pete, Chad at Embree Marine is a guy who can probably figure it out and do a repair if necessary.

[CaptRory]

Reach out to IPHomePort and the IP Facebook group.

[gonesail]

another question is: what does the damaged area look like on the inside .. can you even see that part of the hull?

[NevisDog]

"Oil canning" means the hull is flexing; photo shows a permanent depression - either way, on a well-built IP (unlike a lightly built race-boat) that should never happen, so some serious damage is indicated. I'd suspect very poorly repaired damage from an earlier hard grounding or boatyard incident that may have been exacerbated by the slight stresses from your recent grounding. No good asking us how the repair should be done - the only answer is to have it professionally investigated and repaired by someone you can trust to do it properly this time around. No shortcuts, no cowboys...

[roverhi]

My Westsail ended up with a dent in the hull caused by the wood cradle which had a broken cross member. That allowed the boat to settle onto one of the posts and put a permanent dent in the hull. Fix was to fair out the depression with micro balloons and resin. Fiberglass is a flexible material and will indent if there is enough pressure and may or may not be a permanent indentation dependant on how 'green' the laminate was and how long the intruding force was allowed to remain.

Couldn't load your photo but if yours is a dent caused by ab impact it almost certainly involves delamination of the underlying glass. Fix isn't all that hard but involves cutting out the delaminated section bevelling edge and laminating a patch over the puka, fairing it in and painting or gel coating the surface. Need to inspect any of the furniture and bulkheads in the area that is tabbed to the hull to be sure the glass is still attached. If not, will have to cut away the delaminated tabbing and reglass. All of these repairs are best done with epoxy to insure a bond with remaining surface. Polyester resin does not bond all that well to old cured glass laminate.

[billgewater]

I once checked out a 42 ft vessel that had this problem in lots of places. It turned out to be rampant osmosis and the whole hull was a write off. The second picture shown seems to suggest osmosis bubbles. I hope I am wrong.
An outward facing compound curved surface as this vessel seems to have in the area shown is highly unlikely to suffer from such collapsing as it requires enormous compression if the material is sound.
Looks a real worry to me.
If I was paying a surveyor, I would expect something better than "It's oil canning, mate!" It's about as informative as a car mechanic telling you your car "isn't going!"
Surely he should have been a bit more informative. It looks like you will have to employ a proper surveyor ultimately.

[Fore and Aft]

The only time I have ever surveyed a boat with an issue like that was when the boat had been badly propped for years. The owner did not even know the hollow was there until I pointed it out. When we looked on the inside of the boat there was no cracking in the fiberglass just a bulge. Two years later the new owner finally filled and faired it and a year after that I could not even find the exact spot where the issue was.
I would be suprised if a rock did that,? Fiberglass is fairly flexible and usually bounces back to the shape it was before the impact.
Cheers

[Suijin]

I would not trust the surveyor that called it oil canning. If he’d never seen it before, how can he offer a diagnosis?

I’m almost certain that an Island Packet is not going to oil can on stands unless a huge amount of force is on one stand. It’s just about the last boat I would expect to be susceptible.

It looks like a bunch of paint flaked off in that area at some point in the past. Are you certain that you’re not looking at a bad repair by a previous owner finally rearing it’s ugly head? What’s going on inside, in the bilge? Any broken tabbing, signs of previous work etc?

I also dint think the incident you’re recounting is responsible. If you’d hit something hard enough to cause that there wound be some serious scarring and damage to the exterior laminate.