Deck re-core with weak lower skin...

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Rachel
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Deck re-core with weak lower skin...

Post by Rachel »

Hi folks,

I've been thinking about a Rhodes Meridian that needs a lot of work - especially the deck core and skins.

For those who aren't familiar with it, it's something like a Pearson Ariel - a 24'9" loa, 7' beam Phillip Rhodes design built in Holland in the early 1960s. Outboard in a well.

I had looked at the boat for all of 30 minutes the first time - plenty of time to ascertain that it's a complete project - from the cracking and peeling interior "coating" to the completely toasted deck core... Right now it's also a den of mold.

So today I came down to take a closer look, and to try to decide if I'm going to be the sucker - I mean *person* who takes this one on. I've committed to at least drilling some holes, scrubbing some mold, and taking a close look.

My immediate question concerns the deck re-core. On this boat the coach roof(s) are not cored, so it's just the bow and side-decks. (just -- ha, ha, ha :-). Also, there's no cabin liner - just the woven roving texture and some cracking "bondo-ish" filler that was used on these boats and seems always to have failed.

What I haven't seen mentioned in the deck re-core threads I've found so far is weak lower skins. On this boat, it seems there's just one layer of roving beneath the core, and in this case it's quite delaminated from the wet core, and is sagging quite a bit in a few places (1" to 2"). I drilled a few holes up from below and there's air space between the lower skin and the core. Where I drilled a largish hole, I was able to reach in and tear out a piece of the roving - so it's not all that thick. Although I realize that it's not meant to be strong on its own, without the core and upper skin.

It hasn't sagged everywhere, but there's a good bit of it on one side deck and the foredeck. What I'm thinking is that I would want to add layer(s) of fiberglass to the lower skin before re-coring. I do not relish the idea of working from below, and I also think I would want to prop up the lower skin with some plywood and columns while I worked. So could I just add some glass to the upper side of the lower skin before putting the new core in? Would there be enough "purchase" at the sides where there is a small amount of solid glass (instead of core)? I would like to avoid having to run glass up the side of the cabin and the attendant fairing.

What sort of glass would be appropriate? Also what would be a good layup for the upper skin?

I can feel a million more questions coming, if I take this project on; but the first thing is to decide whether to do it at all. The deck job looms large...

Thanks, R.
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Post by A30_John »

Rachel, this isn't an answer to your question but more of an observation. If you put that kind of work into a 25' boat how long will that boat meet your needs going forward? Will you be keeping it long enough to get back some value for all the time, effort, and money you put in before it's time to look for a bigger boat? In your past posts you've expressed an interest in boats in the 28-30' range. If that's the size you really want, you should be able to find a project boat in similar condition to the Meridian in that size range. You mentioned that it's a "complete project." What else would you need to do?
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Post by bcooke »

How much do you love this boat?

'Cause you are going to need to love it a whole bunch.

I guess I am mirroring some of John's concerns. I thought I remembered you talking (okay writing) about living on the boat. This is a pretty tight boat. There are free projects in larger sizes too.

As to your questions. You can definitely strengthen the bottom skin and should if it sags all by itself...
Come to think of it I don't really know much about this so maybe I should just keep my mouth shut for a change. I will say that my Triton skin is pretty stiff. You couldn't walk on it but it definitely does not sag without the core or upper skin.

It is bad enough when what you thought was a good boat turns out to be a project. When you KNOW it is a project boat... be afraid, very afraid. Make sure you like rebuilding and you love this boat in particular.

-Britton
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Post by bcooke »

BTW Rachel, I know you are an A30 fan. Is $10k for a sailing but needs work A30 too high for your budget?

-Britton
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Post by Peter »

Rachel ... don't walk away from the Rhodes ... RUN
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Post by Tim »

Glissando had a very thin and weak inner skin on the decks. In some places, removing well-stuck core actually tore the inner skin, leaving holes in one or two places that required patching. I patched using some material scraps, but did not add any material to the inner skin as a whole.

You don't need much on the inner skin to do the job that is required by the cored structure. If you added a single layer of something like 15 oz. biax to the top of the inner skin before recoring, that would be more than sufficient, given that the existing weak skin managed to do the job all these years (despite the other deck-related failures). The strength in a cored structure is more about the skins, the effective thickness of the sandwich itself, and an excellent bond with the core on both sides; the additional thickness on either skin (particularly the outer skin) is more about impact resistance than the ultimate strength of the sandwich construction itself.

Take a piece of core and laminate one thin layer on each side; the resulting structure is amazingly stiff, highlighting how effective a cored structure actually is in terms of stiffness versus weight. While there may be many other problems inherent with cored structures, there's no doubt that a well-built one is a marvel of engineering.

With modern biaxial material, you're already ahead of roving in terms of the basic strength of the material itself. With epoxy resin, you're again ahead of the game. So a single layer of biax is far stronger than you think, and probably stronger than two or more layers of polyester-laminated roving and mat, given the general lack of strength of a high resin/fiber ratio laminate found in these old boats.

The air space is the result of your core failure and the failure of the overall sandwich structure. The old core is probably set in wet mat and polyester, not a recipe for longevity and quality. If you shore up the deck from beneath before beginning, and laminate new material soundly, you should be just fine.

These old boats don't have to be re-engineered during a rebuild...they just need to be rebuilt carefully using quality materials and sound judgement.
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Post by Commanderpete »

I like the Meridian, my friend has one.

But if you're looking for something of that size, check out this much-loved Ariel in Maryland. Asking $ 6500. Save you a year or two of work.

http://pearsonariel.org/discussion/show ... ge=1&pp=15
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Post by bcooke »

Geez Rachel, I didn't want to discourage you with this thread. It seems you got some feedback :-)

In a weird sort of way I am glad of my project. I didn't want a finished boat personally because I wanted to be able to look at my perfect (to my tastes that is) boat and have the knowledge and memory of having done it myself. Even now, while the decks are spattered with epoxy, the interior is bare, and the gel coat is dull and crazed and a rather pukish color, I can still look at it and see what I have done and I enjoy that feeling. That is what I was looking for when I bought my boat. If that is what you want and you really like the looks of this boat then go for it. Just make sure you want a project and not a sailboat. There is a difference.

Okay Tim, you have mentioned biax one too many times.

Can you put in perspective the differences between 'regular' cloth and biax? I used biax on a recomendation from you last year but I guess I am still not clear where one is favored over the other. I think I understand matting well enough, i.e. don't use.

-Britton
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Whew!

Post by Rachel »

Hi all,

Thanks for all the responses - it's great to log in and see so many replies! :-)

All your thoughts pretty much echo my own, which is why it's a hard choice as to whether to go with this boat or not.

I will say that the Meridian - and to some extent its 28' sister, the Ranger - are really my first loves. Functionally, they're very similar to the Ariel and Triton, but there's just something about them that draws me in. Which isn't to say that I don't really like Tritons and A-30s, because I do, but just to explain that the Meridian and Ranger have even just a little more swoon factor.

Now on the one hand that might lead a person to be less than objective, but, OTOH, the swoon factor is a big part of why I love boats, and it's not like I'm buying a toaster or a drill... :-) I should also add that re-sale is not a major factor in my decision. Not that I won't ever sell, but I don't see any boat I buy at this point being an investment. I do realize that a careful boat purchase can nearly guarantee one a good return, but I just can't imagine any project boat being a good investment - at least not in my range. At any rate, I'm not looking at it from that perspective.

As far as small size, well, that is one of the negatives of the Meridian. While it's fantastically large for a 24-footer, with standing headroom, copious cockpit lockers, and a nice galley; it *is* narrow, at just 7' beam, so that limits the layout somewhat.

On the plus size, there's that much less of everything to buy, and the project looks a bit more doable. I like the outboard-in-a-well, for my situation, anyway. But if I found a Ranger/Triton that was just the same, I'd certainly go for it.

As long as we're getting down to brass tacks here, let me just say that my boat budget is about $4000, with maybe a little room for leeway but not much. I have found two Tritons that didn't need deck re-core jobs for that price (should have bought the first one, but it was the first boat I looked at; the second one I committed to but got scooped on - drat), but they had other problems - non-working engine, no sails, severly crazed deck, etc.

The Meridian is free. Not that any boat is free, as we all know, but most of the boats I've seen in my price range need a lot of (or exactly) the same work. With the boat being free, I've got money left over for tools and materials. Granted, I'd get more for my money with a $10,000 boat - and I'd dearly love one - but that's not in the cards right now or anytime soon, unless that's my ship I see on the horizon....

What the Meridian does have is a decent suit of sails, wooden spars in good condition, an outboard motor that either runs or will be easy to replace, oodles of nice bronze, and exterior wood trim that can be salvaged without too much trouble. Most of the interior structure is fiberglass, so it should be fine under the mold (settee bases, etc.) What it needs is a re-core (but the cabin tops aren't cored so that helps somewhat), a bunch of sanding/grinding/fairing inside on everything above the hull/deck joint (ugh - where they used a weird filler at the factory to make it look better, instead of a liner).

I *am* going to look at a Ranger this afternoon that is $6000/negotiable, but I have a feeling it will be a cleaned up version of the Meridian, ie. not moldy and gross, but needing a deck re-core, interior work, etc. I know that it has been grounded and an amateur repair made to the aft end of the keel (where the false keel would be on a Triton but the Ranger was made in two halves so even though it has an external ballast pig it has a deep bilge aft of the keel). Other than that, well, I'll let you all know what I find...

And of course I'm always open to other options; but I will have to make a decision one way or the other on the Meridian this week. Until then, well, you know what'll be on my mind...

Again, thanks for your input everyone. And Tim, thanks for the information on how to deal with the lower skin - I had the idea that all the Tritons had a really strong lower skin; good to know that just adding the 15 oz. biax would probably do the trick. Sandwich construction is amazing when it's not failing.

--- R.
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Ariel link not working

Post by Rachel »

I forgot to mention this in my last post - CommanderPete that link to the Ariel doesn't seem to work for me...

R.
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Post by bcooke »

You are hooked. It is too late now. You should soon begin feeling the pull of the vortex that sucks you ever downward into a black, sticky, pool of steaming epoxy resin. Enjoy the ride :-)

-Britton
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No!

Post by Rachel »

You are hooked. It is too late now.


No! I can't be hooked yet! There's still time (isn't there?); I'm even looking at another boat today, give me credit! ;-)

And it's true, the Meridian is *way* too small. Suddenly a Triton looks like the height of decadent luxury, space-wise.

But I will admit that suddenly "having" a large tools and materials budget (as opposed to spending my whole budget on a boat and then still needing stuff but not being able to afford it) is very seductive.

And those Meridians are so beautiful (by the way, Tim, feel free to post that deceptively-nice-looking photo of it dockside that I sent you - I'm not sure how to post pics yet...)

Ah, boats :-)[/quote]
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Post by bcooke »

There's still time (isn't there?)
Nope.

I was thinking about telling you about a Triton project in my yard that the owner wants $2000 for but could probably be convinced to take half that. But then it would take$10,000 to get it sailing again. Don't underestimate the total costs of a rebuild. $4000 will get you started but... well... maybe you are more sensible than I am :-)
And it's true, the Meridian is *way* too small.
Too small for inviting your high school class for a summer cruise maybe but a small boat is better than no boat. Compared to living in a car it shouldn't be too bad.

Last piece of advice which I finally took for myself today too. Walk past the gallon cans of epoxy. Go straight for the 5 gallon jugs. You will save a lot of money and will use every drop.

-Britton
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Post by Tim »

bcooke wrote:Can you put in perspective the differences between 'regular' cloth and biax? I used biax on a recomendation from you last year but I guess I am still not clear where one is favored over the other. I think I understand matting well enough, i.e. don't use.
Without getting technical, here's my best take on standard "cloth" versus biax.

Cloth is generally a 90-degree fabric--fibers run in a square pattern at right angles to each other--and features woven fibers, like a basket weave. Woven roving is simlar to cloth in that it features 90 degree fibers, though in this case, they are bundles of fibers woven together. Because of this woven design, cloth holds together when dry; the edges are usually stitched.

Cloth is best used as sheathing, and for coating. It is relatively smooth, as the fibers are small, and it is easy to wet out. The light weights--up to 6 oz. or so--visually disappear when wet out. Cloth isn't that strong in the grand scheme of things, and it takes a lot to build up any real thickness.

Biax is a broad term encompassing any material where fibers run at angles to each other, usually 45 degrees. The fibers in a biaxial cloth tend to be lightly stitched together to hold them in place when dry, as they are not woven together. The orientation of the fibers makes biaxial cloth stronger than regular cloth, and with proper equipment a higher fiber-resin ratio is possible with biax than with cloth. High fiber to resin ratios are desirable for greatest strength and lightest weight.

Biax in various weights is a good all-round choice for structural laminates, as it is strong and builds up thickness quickly. Many biaxial fabrics have a light layer of mat stitched to the bottom.

Biax tapes are a great choice for structural tabbing, because all the fibers cross the joint at 45 degrees; with cloth, half the fibers run parallel to the joint, weakening the bond.

Mat has its place, but is never a structural material. When using traditional roving, each layer must be alternated with a layer of mat to make a proper laminate.

Basically: use biax tape and fabrics as a general material for real laminating, structural applications, and so forth. Use regular cloth for sheathing, encapsulating, and the like. I like to use a layer of cloth over the top of biax material to soak up excess resin and leave a smoother finish behind; biax is very rough when cured. I always sand new glass no matter what, since I like a smoother surface, but the cloth over the top makes this job much easier, and less material is removed.
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Post by Tim »

bcooke wrote:You should soon begin feeling the pull of the vortex that sucks you ever downward into a black, sticky, pool of steaming epoxy resin...
Why is your epoxy resin black? ;<)
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Post by bcooke »

Why is your epoxy resin black? ;<)
Poetic license. Honey amber didn't convey the proper image. :-)

So all this time I could have been using more biax and probably have been done sooner.. Oh well. At least my nine yards of the stuff won't continue to gather dust. Thanks for the info.

-Britton
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Post by Peter »

The Meridian is free. Not that any boat is free, as we all know, .....
Free you say? Ahh ... in that case I withdraw my "Run" remark. You can do a lot of work on a free boat before you break out that first thousand ... really get to know it while cleaning and taking it apart.
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Post by Tim »

bcooke wrote:So all this time I could have been using more biax...
Biax is good for a lot of things, but it is more difficult to work with because it is stiffer and thicker, and won't conform well to tight radii or corners using traditional hand-laminating techniques. It also takes quite a bit of resin and effort to fully wet all the way through; excess resin can be squeeged off once the material is saturated, preventing unneeded buildup.

Still, it's one of the best choices available for normal building and reconstruction projects.
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Free boat

Post by grampianman »

Rachel,
I got a mouldy, rotted-wood small sailboat for 'free'. The sails were in good condition, the hull sound, the standing rigging free of spaniards and cracks. A lot of bleach and scrubbing helped clean the boat and my family and I enjoyed two years of pretty constant sailing here in Florida before the piper had to be paid. Now I'm approaching the ninth month of a major repair/reconstruction on my 23 footer. I only regret having to spend time on the boat and not sail in what seems to be one of the breeziest springs I can remember. On the other hand, I will have a stronger, safer and better equipped vessel when I relaunch.
Your situation obviously will dictate your decision, but when I sail, I don't care what the boat is, as long as I am sailing.
And as a final caveat, smaller can be cheaper.

Cheers,
Ian,
Wing & a Prayer, Grampian 23
Steve480

Post by Steve480 »

Hi Rachel,
Our Triton (480) also has a thin inner deck skin. The inner skins almost had the feel of a trampoline skin. One spot tore a bit when we lifted a topskin panel during the recore process. It was very satisfying how strong the new deck felt once we got the new core and topskin down and sealed up. Truly a synergistic experience.
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Post by Commanderpete »

Rachel, that link to the Ariel seems to work. I'm not certain that it's still for sale. There's some more pictures of the boat here

http://pearsonariel.org/discussion/showthread.php?t=433

I may be talking heresy, but there are few things more expensive than a free boat.
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Thanks again

Post by Rachel »

Britton, I'm sure that epoxy will *seem* black to me in the end if I do take this project on, and Peter, I'm glad you recanted that HUGE version of the word "run." A smaller one might still be appropriate though ;-) And yes, although the Meridian would be a bit small in the end, I also realize that the project would be quite a bit smaller, so there are pros and cons. Thanks to everyone for your thoughts.

I guess I'm straying a bit off topic here, but the thread did end up getting into my boat shopping, so I'll continue...

Yesterday I looked at a Rhodes Ranger going for $5000. They are lovely boats - and very similar to Triton in size. And although the decks weren't caving in, and could probably have been nursed along for a number of years, the boat just really wasn't that much better than the Meridian (except a bit bigger). And no money left over for tools and supplies. There were many more details of course, but that's the feeling I was left with.

Coincidentally, my panic over what to do with the Meridian was eased somewhat. The story is that the original price was to be in the $1500 range. The owner described the boat as being in nice condition. Well, I got there and discovered how horrible it was (this was a few weeks ago), so I called the owner and asked him when he'd last *seen* the boat. Turns out it had been nearly two years - I believe he was a first-time boat owner who didn't realize that you couldn't just lock it up and leave, like a storage unit...

I offered to send him photos of the current condition (he lived a long distance away), but he said that no, he preferred to remember it the way it was when he first owned it. In the end he asked if he could just send me the title and could I either fix it up myself or find it a good home. Oh, and by the way, the slip rental was due last week....

The plot thickened when the slip was rented to someone new (with a different boat) as of May 1. And I couldn't find anyone nearby who was willing to haul the boat out of the water; this time of year it seems to be like moving towards the back of the airplane while everyone is waiting to disembark - impossible and very unpopular.

Then yesterday the new slip person backed out (ah the twists and turns of boat ownership). So I decided to pay for the minimum of 3 months of slippage ($300) just to buy some time for now. They said they could haul it in early June. I have some things to do in Wisconsin for the next month or so anyway, so that's fine by me. If something better comes up in the meantime, I will keep an open mind, but otherwise I'll probably go ahead with the Meridian.

Meantime, I intend to see if I can come up with a better plan for working on it. As it is, if I do it at this marina/yard, I have to pay for the slip *plus* $4 a foot per month to be on the hard. That sounds like too much and I'll feel rushed. In my wildest dreams I couldn't imagine having the boat ready anytime this summer anyway, so I have no need for a slip.

One option would be to trailer it "home" to NW Wisconsin where it'd be cheaper to store and I'd save money by not having to run out and buy all those little things that I'd have at home (just getting stuff to clean the boat has added up). I could also start on it sooner. Of course I'd need a trailer. Or perhaps I'll find something better locally (Baltimore/Annapolis area).

But back to lower deck skins (on topic!): Tim, I think the biax sounds like a good idea; does that rough surface pose a problem if I put it on top of the existing lower skin and then core on top of that? Or would the thickened epoxy surrounding the new core take that up? If I'm worried about strength, is that a reason to use marine ply over balsa (I know, that's not how it gets its strength, right?)?

I will post some photos when I'm back home and able to do so.
Thanks again everyone --- Rachel
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