Fiberglass skin on old plank wood boats

Peter, the Vaitses method is a bit different in that it uses a substantial sheathing with mechanical fasteners. He does this for a few reasons, which are logical, though unnecessary considering modern resin systems. The sheathing has become progressively thicker because it needs to be for the fasteners to hold, which is as you know, just compensation for the lack of peel strength with polyester resins on wood. Secondly the new hull shell, which is what it essentially becomes, has to be sufficiently thick, to prevent moisture vapor penetration. The logic behind polyester is that it's fairly cheap, but it needs a good bit of mat, fabric and fasteners to make it work.

An easy argument can be made with an epoxy sheathing, including costs. Strength, stiffness, peel strength on wood and water proofing are all much superior to polyester based sheathings. Coupled with the fact you don't need half of the fabrics, none of the mat or any fasteners, means the resin costs are amortized in other material savings, plus it's actually water proof at a much lower weight burden. These facts have been proven time and time again. Test after test it's so, but some just can't let go of what they know, preferring to stick with it, maybe adjusting the magic formula to suit increasing insistence for a competitive prospect. You have to remember some of these folks still think epoxy is a fad . . .

During the recent hull repairs on the USS Constellation (okay mid 1990's is recent ain't it), considerable pressure came to bare, in regard to longevity, durability and maintenance. Sheathings were discussed mostly as a way to have a historic monument that required less maintenance. Polyester wasn't discussed for obvious reasons and the eventual repair was a cold molded hull shell, with epoxy of course. This hasn't been without issue either, as they have developed rot in the new cold molded hull shell, but it was from previously undetected rot in adjoining areas that kept it going, also sweet water leaks and from dings received in use, that breached the encapsulation. Nothings perfect, but polyester on wood is half a century old technique that has long been replaced by much better materials and techniques. Unless of course you are in the Silver bird camp and think that I, the folks at West System (and the others) and the folks over at Tri-Coastal Marine (and others) are all full of crap.

 

One small point, PAR. Vaitses did invent that particular method (unless you can show me who did?), was the guy from Massachusetts the op was asking about and he "wrote the book" on the method - literally.

We are in agreement on a lot of the points you make (last resort technique, etc), but there are boats from the 50's, glassed over in the 70's, still floating today. Obviously it works, since there are real life examples out there (I've been aboard one in Freeport, Maine.)

It's not the be all, end all best solution out there, but it is appropriate in some cases and shouldn't be completely dismissed.

 

He did get hit by lightening................

I've been involved in some very successful GRP sheathing of 40' timber vessels in the early 80s, that's 30 years ago, the vessels were @40 years old at the time & are still in work now. The vessels were in good condition with regular maintenance & repair & the sheathing used a Ciba Geigy epoxy & powder bound choppy. Jeff.

 

I think thats very fair but its still what I call ---bogging it up.

If the boat is so rotten that it cant be repaired properly, then --bogging it up-- is just making a rotten boat water tight.

May work --may not -- no matter how you look at it,--- its still bogging up a rotten boat.

 

You're not supposed to glass over rot. The author says this in the book. You need something reasonably sound in order to glass it, or it won't last.

 

If its sound then why glass it?

 

The success stories of the majority of these "treatments" are in the hands of caring owners. Had the original yachts been in these hands, they'd likely not have needed it. This isn't to say there haven't been successes, there have, but you have to look at the whole picture. I lived through the wonder years and eventual realization of polyester resins on wood. When I first started, we were pulling polyester skins off everything or condemning fine pedigreed craft, because of polyester skins.

Try to sell a polyester skinned wooden boat. You can't sell it? Why? How come the insurance companies will not touch them either? What happens to a Rhodes 33 when it's received this treatment? I remember pulling about a 1/4" skin off one in the late 70's, as it added 50% to the boat's weight!

It's not that you can't make this system work, you can on some boats, but it's the duct tape approach that most have issue with. The resin doesn't have the modulus of elasticity to work with the substrate, a classic engineering mistake. So, it's "doctored" up with mechanical fastening to help. The mechanical fastening needs a particularly heavy skin, or they pull out, so the skin is made absurdly heavy, for the job it's asked to do, another classic engineering issue. The resin selection isn't water proof enough to prevent moisture vapor penetration, so they make sure the skin is thick enough to offer this too. Any composites engineer or experienced laminater, would switch to a different resin system, one with an elongation attribute, more compatible with the substrate it's being applied. While you're making the resin system change, it would be nice if other physical properties also were more compliant and compatible with the substrate, so you could eliminate or reduce the other materials in the matrix.

If well matched, as I previously mentioned, you could have a skin, at a fraction of the weight, using much stronger directional fabrics, no mat and no mechanical fasteners. What's not to like about the reasonable evolution of a process such as I've described? This is in fact why Mead and his brother got started fooling around with epoxy in the 60's in the first place.

Vaitses didn't invent it, but did write the first book about it. This is like saying Glen L. Witt invented boat building in plywood. It was a fairly common thing in the late 50's and early 60's to have this done. Everyone had their own "special mixture" and technique. The material was considered the wonder goo, that could save wooden boats once and for all. The jury came in about a decade later and it wasn't what everyone had hoped for. The countless hundreds of home built boats resting in the back corners of marinas, with tattered remains of the non-mechanically fastened sheathing, a simple testament to it's inability to stick to wood. Not to mention the thousands of "saved" working vessels that were dragged to the land fill or out to sea for one last run.

In the early 70's things began to change and new resins started to show up, but the experienced repair personal "had seen this sort of thing before" and were understandably skeptical. "Another wonder goo", oh please . . ., but eventually some really amazing stuff was being done, races won and records getting broken. The tests came back, the jury too and the rest is reasonably well documented.

Given a 10 ton 40' yacht, would you apply a 5/16" polyester skin of stapled mat and roving, for a substantial percentage of the boat's weight or would you apply a 1/16" epoxy set, bi-directional sheathing, skip the mat and hold the fasteners, for a fraction of the weight? Take a guess which one costs more to do.

 

A couple of different reasons, if I recall:

Reason 1) The boat is not very sound and you want a few years out of her before you scrap her. Those are known to be just a quick extension to an otherwise dead boat, mostly done by commercial folks to make a couple more years of money.

Reason 2) The other reason is to avoid all the labor needed to upkeep a traditional wooden boat. To basically give up and convert her over to a more stable (though heavier) configuration that isn't as likely to rot away or need a lot of parts replaced constantly. In this example, you could purchase a fine, 60' wooden boat from the 1950's or something, make sure it was in good enough shape for the glass job, glass over it and have something that will last you a lifetime just like a fiberglass boat. (supposedly)

Of course, it's not the best way to do things, but people do it and the boats last (or fall apart in 3 years if glassed over a boat that is already one foot in the grave).

PAR, I agree 100% with your last post. I can't imagine going out of your way to go and find polyester to do this method anymore. It's from the past. The new resins and directional fabric (no mat) would, of course, do a much better job and keep some of the weight off. I'm just saying the guy has a technique someone can read and follow. A technique that was successful at the time. But yes, I'd definitely use the modern materials over the older ones. Would be crazy to use polyester the way they suggest in the book.

 

That has been my question all along. If you have to get rid of the rot and replace it with good wood to make this work, why not just go all the way and repair the boat the way it should be repaired. Why use a stop gap half measure to get a few more years, when you can fix it right and have it last far longer. As some one said, this is a way to save a lot on costs of materials and labor. Why try to save money in the short run, when you can spend a little more and end up saving far more in the long run? Penny wise and pound foolish. My feeling is, if you can't afford to do it right, why not sell the boat to someone who can, and get yourself a boat you can afford.

I do understand how some people feel about their boats. They are almost family. But would you give family the same kind of half way medical treatment? No you wouldn't. So why do it to a boat when you are essentially resigning it to an landfill. (I said almost because some times this does succeed)

Anyway, I've put in my two cents (or 5 cents in Canada where they have done away with pennies)

 

Actually, it's usually cheaper to have a carvel hull repaired, then it is to have it 'glassed, like this. Of course depending on the level of neglect and structural damage. If a wooden boat is maintained, there's usually no surprises, unless you tend smash into stuff.

 

As I mentioned in an earlier post last summer in western and northern Newfoundland and in Labrador we saw many wood boats covered with fiberglass. The ranged from 16 foot or so open outboard powered skiffs to 40 foot or so "trawlers". Some of the larger boats had lettering on the side advertising the company that did the fiberglassing. As far as I could tell fishing is mostly a marginal business in that part of Newfoundland and Labrador, much smaller than it was before the closure of the cod fishery twenty years ago, and the future is very uncertain.

The boats are used to carry heavy loads. The added weight of the fiberglass probably is not as noticeable as it would be on most pleasure boats.

Both air and water temperatures are much colder than most of the US. Water temperatures don't get much over 50 F during the short summer on the west coast of Newfoundland, and are colder on the Labrador coast. Air temperatures much over 70 F are unusual during the summer. The boats are in salt water. My guess is rot progresses considerably slower in Newfoundland and Labrador than it does in Florida.

So it appeared to me that the factors in the "equation" for fiberglassing a boat are different there than further south. Added weight not as noticeable. Future income from owning a boat very uncertain. Rot doesn't progress as fast.

 

Thats what PAR said that caused the outrage of some.

At a yard in Phuket called Ratanachi they keep wrecks in the river. I wasnt aware that they were waiting for repair. The were wrecks with ribs bare sticking from the mud.

One day they rowed across with a chain and dragged out half a boat full of mud with bare ribs, you could see straight into it the STBD side was missing.

3 months later it was engined tanked and out fishing, good as new.

No glass at all.

They cut out huge ribs by eye with a chain saw and they fit ist time.

I can stand in that yard all day. But Ratanachi is just one of thousand on every river.


http://www.ratanachai-slipway.com/service.htm

http://www.pss-satun.com/photos.html

 

Thanks for the very interesting facts. In that case fiberglassing/polyester may become interesting with a lot of mechanical fastening. But truly it sounds like desperate measure for fisherman with a uncertain future.

 

Fibre glass and wood expand and contract in different ways and flex entirely differently.
Surley it can be understood that eventually the mechanical bond will deteriorate into delamination .

 

I do agree. Classic wood boats are made with hundred of pieces that can be exchanged. A well maintained (and well built at first) classic wooden boat can last a very long time (more than fifty years) if it's constantly maintained and repaired when needed. That asks for a sharp eye, with a lot of linseed oil and Norwegian pine tar, plus buckets of a good paint.

Generally the complete revision is made when the hull paint has to be completely taken out, so every 5 to 10 years. I had with a friend a small fishing boat made with oak (slightly under 5.50 meters so it was not registered ...so no taxes) with an antic 8 HP diesel.
Built nicely around 1935 by the local naval carpenter (bronze screws as the oak is known to eat any steel even double dipped galvanized).
Professionally used until around 1970-5. Painted every spring and the initial 4 coats plus 4 coats of yearly paint were removed every 5 years by its successive owners.
Great revision and just a few reparations were needed each time like a plank or a rib.
I sold it in 1993 when my friend died. It was totally sound except the engine which ceased thumpering after a few decades of work and was replaced by a 9.9 Honda outboard. On 2003, date I got last news, the boat was always navigating every year from Easter to October with a new coat paint...The climate in Brittany, although humid, is pretty fresh and the UV are not very fierce, as pointed by Dcockey that helps.
Also I saw several pro fishing boats around 30 feet almost 50 years old and sound.
The cheaply made ones would need a big job at 10 years and last 15 to 20 years at best and ended rotting in some marsh.

Like almost all materials if it's well built that will last 30 years surely.