lifespan of a wood-epoxy boat

[jorgoz]

I've just read a thread on the boatdesign.net. It mentions the not so long lifespan of a wood-epoxy boat and the reduced resale value. The post mentions the epoxy will eventually start to crack and let water inside, and the the boat would start rotting inside out. The auteur of this tread gives a wood-epoxy boat between 10 to 20 years before cracking occurs. What about this ?

George

[wolfietuk]

In his book Sam devlin talks about a 20year + lifespan. I would think this is average, and depends on how the boat is used. The newer epoxies are getting better all the time. That is also probably time for a refit and rebuild.

Rick

[Scott Rosen]

It would depend entirely on the construction methods used and the quality of the work. There are cold-molded epoxy and wood boats that are older than 20 years and doing just fine.

[Mike Vogdes]

Yes, what Scott said...

The boat I'm building now calls for 3 layers of 12oz biaxle tape (good stuff) over 3/4" filets on the inside then you bond and screw all your structural members in, keel, stringers, floors, sheer clamp, blocking and then a layer of 12 oz biaxle tape on the outside seams then followed by a skin of 6 oz cloth, then your keel and bilge keels. If done correctly this will last a long long time. (strong like bull)..

At this stage the hull would be flipped and the deck framing and cabin structure will only add more streanth to what you allready have.

Of course good construction practices must be followed and the use of good material is a must. Lets not forget the proper maintenance thing as well. If you neglect this boat it will deteriorate just as fast as any other boat reguardless of what its made of.

[NormMessinger]

Well now. THere's epoxy and then there's epoxy. Eh? And all are not created equal. One might guess all do not grow old equally either. My Long EZ is 18 years old. Shall I expect the wings to fall off in two years. That'll be one wild ride. But I think not. There are folks in aviation who assert some epoxy structures only get better with age

Boat wise there are to many variables, seems to me. Anyway, what will last longer all things being equal?

[Don Maurer]

The author was probably referring to epoxy over fir plywood with no fiberglass sheathing. Fir plywood has a tendancy to check, which would let in water if not maintained. Other marine plywoods are not susceptible to checking. If properly maintained, it should last indefinitely.

[Keith Wilson]

FWIW, Sam Devlin's boats are well and truly sheathed in glass and epoxy. In fact, they look a great deal like fiberglass boats. How he manages to get that kind of finish and still make any money, I have no idea. I think he says "20+ years" because the technique is new enough that there are not that many wood-epoxy boats older than 20 years. The clock's still running; they may last 100 years or more, but we won't be around to find out.

If you're really worried about the boat's longevity and are totally averse to surprises down the road, build it traditionally out of the best wood you can find. It may not last any longer, but eveything that can go wrong has already been discovered over the past several hundred years, and you can replace one piece at a time. That's not what I'd do, but it's your call. There is, however, no evidence (yet) that a well-built and reasonably well-maintained wood-epoxy boat won't last a very long time.

[ 01-26-2003, 12:44 PM: Message edited by: Keith Wilson ]

[George Roberts]

If you use too much wood and too little epoxy/cloth or too little wood and too much epxoy cloth, the life span will be reduced from the optimal mix.

I don't know what the optimal mix for life is. I suppose a lot of builders don't also.

[Charlie J]

Well lets see. in 1975 I started construction on a Cross 35 Ketch rigged trimaran using WEST sys over cedar coldmolded hulls, with fir plywood decks. I launched the boat in 1981 and lived aboard til I sold her in 1984. She's on her third owner now (I have kept in touch) and is still regularly passing surveys with no structrual troubles what so ever. I expect her to still be going strong in another 10, 20, 30 years, given proper maintenance just like ANY boat, built of ANY material.

The boat had wood/epoxy diesel and water tanks, which are still in use last I asked.

So I think he's feeding a crock.

[ 01-26-2003, 11:51 PM: Message edited by: Charlie J ]

[JimConlin]

In this years's Chicago-Mackinac race, the second boat to finish was Meade Gougeon's Adagio.

The first complete boat built incorporating WEST SYSTEM epoxy and composite construction techniques was Adagio. This 35-foot trimaran was designed and built by the Gougeons and launched in 1970.
[from the Gougeon Bros. site ]



If a well-engineered and well-made wood-epoxy boat is racing successfully 32 years later, i think i'll stop worrying about the materal and concentrate on using it well.

[JimD]

George, I asked more or less the same question a few months ago and received several testimonials that encapsulation/fiberglassing seems to work long term, at least in so far as it can be measured long term given the relatively short history of its use.

So far as I understood the responses I received you shoud do fine as long as you are meticulous while building and do not ignore frequent inspection and maintenance. I am not a professional but have committed more than a few paycheques to my amateur epoxy/wood projects so I hope its all true [img]smile.gif[/img]
jimd

[cmorse]

Having owned two of Sam Devlin's boats, one of which is now 22 years old, I can say a wood/epoxy boat lasts 20 years plus. The Dipper, which I have since sold, is going strong and had seen quite a life with various uses. I currently own a Surf Scoter which will be 11 years old next month. Also, the surveyor I used for both of these vessels said that Sam's boats and his methodology is withstanding the test of time. He has surveyed a number of his boats and said they all are in fine shape.

[gary porter]

George, one factor that will come into play on any boat is, does it live in the water or is it trailerable. In any case it all comes down to how well a boat is taken care of and that applies to any method. Plywood in itself if good quality to start with has no more tendency to deteriate than anything else. Many, if not most of us, have houses that take a lot of abuse and harsh weather and are sheathed in plywood. Yes , I have known of some batches of ply that delaminated on houses as well. Again it is very important to start with quality. There are also some relatively new products that are very useful as structural components of plywood built boats. One in particular is that of LVL, Versalam beams etc. I have swithed from standard 2x doug fir to the Versalm beams for stringers. They are stronger, stable, and it doesn't take two hours of picking through a lumber pile to find one that is straight and not cracked. If taken care of properly I see no reason why a plywood built boat shouldn't last as long as any other. My two cents.
Gary

[jorgoz]

Thx guys for the reassurance. I didn't want to believe what he said either, but it's always better to check with people who know their stuff . No i can continue with a settled down hart . Can't wait till i finish my first wood-epoxy runabout (outboard).

Later guys

[ccmanuals]

Like anything else, epoxy has it's place and then there situations it shouldn't probably be used. For example, if you are restoring an antique and classic runabout or utility then there is a very large growing school of thought that it should not be used. You can see an article by Don Danenberg here that talks about this.
http://ccmanuals.crosswinds.net/docu...mmonwisdom.htm
But, let's say you are building a new boat and are enscapulating the frame than it may be the way to go. It all depends on what you are trying to accomplish here.

[John Blazy]

Let's do a comparison since this thread is well concluded. Compare a fiberglass boat with a stich-n-glue sheathed epoxy wood boat (both same size, say 15 ft. and put together state of the art according to identical structural load requirements - where the woody would be lighter). Lets simulate two years hard wear on bottom of hull without maintenence on either, and that wear results in a total of forty sq inches of puncture of the protective layer (glass/epoxy on the wood boat, gelcoat and 1st layer of glass on polyester boat) of each exposing water to the raw plywood of the woody and the raw glass of the plasticky. Now fast forward ten to twenty years, on the boats left in the water the whole time with no maintenence (much harder to believe with the woody). Which will rot and sink first? If not sink, which damage is most extensive? I have very little bias - truly don't know which would last the longest, even with marine ply of 3/8" or more I would guess that the woody would sink first.
Any stabs at this? - JB

[Andy Bangs]

In 1984 my Kitrtery Point friend Bill Bailey made me a 16' "expedition boat" (very similar to a square tail canoe) with two layers of cedar laid crosswise, held together with epoxy. She's coating sensitive, as Bill puts it — meaning that every year I put a few layers of varnish on her. After 19 years of fairly rough usage she's still tight and tough. I use her in both coastal and inland waters, occasionally bouncing off rocks. When the varnish is cracked I sand and patch. Bill agrees with me that she's worth another 19 year if I treat her right.

[JimD]

Originally posted by John Blazy:
Let's do a comparison since this thread is well concluded. Compare a fiberglass boat with a stich-n-glue sheathed epoxy wood boat (both same size, say 15 ft. and put together state of the art according to identical structural load requirements - where the woody would be lighter). Lets simulate two years hard wear on bottom of hull without maintenence on either, and that wear results in a total of forty sq inches of puncture of the protective layer (glass/epoxy on the wood boat, gelcoat and 1st layer of glass on polyester boat) of each exposing water to the raw plywood of the woody and the raw glass of the plasticky. Now fast forward ten to twenty years, on the boats left in the water the whole time with no maintenence (much harder to believe with the woody). Which will rot and sink first? If not sink, which damage is most extensive? I have very little bias - truly don't know which would last the longest, even with marine ply of 3/8" or more I would guess that the woody would sink first.
Any stabs at this? - JB

[img]smile.gif[/img] John, I preface with a smile in the hopes my comment will be taken in a good natured way, but anyone who treats a boat like that deserves to have it sink. I conclude with the same good humour and intentions [img]smile.gif[/img] see?

But given your criteria I have a hunch the wood boat would be in very sad shape. It happened to one of my kayaks in far less than 10 or 20 years. The glass sheath was breached, water soaked into the ply layers and couldn't get out, and the wood turned to sponge in no time. I had to cut out the bad bit and patch it. I have no experience with glass boats. I like working in wood, don't want to take on the unique set of problems that come with traditional plank so I glass them. One way or another it pays to take care of your boat.
best regards, jimd

[SailBoatDude]

If any one left a 15 foot boat of any construction material afloat for that long a period and no maintenance, it would deserve to sink and the owner banned for an equal amount of time from ever owning another boat. We see this more and more these days, boats on their rode or slip hoping for an owner to stop by and lend a hand. Once the family can afford that second mortgage, it's off to the trailer mounted pony farm for a new soon to be out usefulnessed, plastic fantastic something or other. Then it becomes a statistic, one of the 20 hours per year use we read about for the outings of the average pleasure craft in this country.

Seamanship is the only way to have a boat for a long time. With care, a poorly constructed boat, of any method, can survive and provide pleasure for it's owner. You can bitch and wine, but the work HAS to be done or you'll pay later in shorter life span and bigger repair bills. There's no short cut - not even epoxy, who's jury is still out, but making a fine showing for itself - just plan old scheduled crap, we'd wish we didn't have to do, but putting it off is worse, so we do anyway.

I've seen hundreds of boats die in my day. The many in my youth that have long since been plowed under in a field, the blistered and rotting hulks that dot every marina. All have the same sad story and it ain't epoxy . . . it's bad seamanship and there's not much excuse for it.

[John Blazy]

Kindof ironic to drive by a YACHT CLUB and see its similarities to a hillbilly front yard full of neglected old rustbuckets, eh Sailboatdude? Hillbillies with money, I guess.

[George Roberts]

gary porter ---

I applaud your creatitivity.

I should point out that LVL and similar engineered lumber is not designed to go through wet/dry cycles.

Eventually even epoxied LVL will go through wet/dry cycles.

Eventuall LVL will fail in your application.

I wish I could tell you how long it will take, but it depends on how well the boat is maintained.

[Dave Wright]

To George Roberts,

I was considering using some LVL. I thought perhaps it would give equivalent performance to some frames I'd laminated up with weldwood glue (water and powder) in the past. I was going to coat the LVL with epoxy and glass.

I don't want to do something that might be problematic, so re your comments: Do you have direct personal experience and observation (not second hand) of failure of LVL used in a boat framing application? Or, perhaps have you personally tested LVL materials, say a simple boil test, or other test?

I hope I'm not sounding discourteous, I'm just trying to make a rational decision on the use of LVL. Please elaborate on your experiences with the product. I'm going to head over to Home Depot this afternoon to see if I can scrounge a chunk for a boil test.

Thanks much,
Dave Wright
Seattle, WA

[gary porter]

George, thanks for your comments, In my case the epoxy coated LVL is an internal structural part of the boat ,,,stringers, that do not normally come into any contact with the water. Of course as with any boat there is present moisture in the air etc.
Is it your opinion that the LVL stringers will fail, delaminate or whatever faster or sooner than the marine grade plywood that the boat is made of?? If so why, this would be of great importance if you have evidence or specific reason to think so. If it is just your opinion ,, well thats fine, but seriously its the first I've heard of it. It has been my assumption that the LVL (Versalams) that I'm using are exterior grade glued,,,looks like resourcenol (sp). I've sent an email to Boise to ask for conformation etc on this.
I'm very serious about turning out a good product so I don't take a statement like that lightly.
Thanks again..
Gary

[JimConlin]

Somewhere, i've read that one determinant of the life of a boat is how attractive it is. Someone's demonstrated that attractive boats get maintained better and therefore live longer.
I own two dinghies, a chopper-gun FG thing and a well-made (if i do say so) plywood pram. I like the pram and i don't particularly like the other. I guarantee that the FG thing will go to the dump long before the pram goes.

[Old Salt]

I believe that there are a combination of things going on here. First epoxy is a relatively new product. We have a lot of traditionalists here that are hesitant to accept this method of construction. Its only been a few years since epoxy/plywood boats were rejeceted from being published in the Launchings section of the magazine. The next issue is that not all plywood is created equal. Third is the attention to details in regards to encapsulation of wood. Forth being maintenance. These set of variables provide the opportunity for us to form our own oppinions about the products longevity...based on our own bias.

Based on the time available to most of us...the method of construction has been resposible for recruiting more first time boat builders than would have based on the traditional boat building learning curve. This increase in interest is good for everyone. Supplies are becoming more available due to more sales and interest. The same feeling of pride can come from an epoxy plywood boat as a planked boat with steam bent frames. It is all good!

The jury is still out. Please dont be so quick to get on your soapbox and use every opportunity you get to prove how traditional construction methods are superior. You sound like someone arguing the merits of the horseless carriage. IMHO

[Stu Fyfe]

AMEN, Old Salt.

[ishmael]

Having done a little of both types of construction, I have nothing against cold molded or encapsulated ply. Well done and kept up it should last for generations. I just would prefer not to build that way again.