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Agri 04-15-2012 11:45 PM

Glassing a old wood hull.
I'm still 4-6 months away from starting to seriously shop for my next boat, however I've been keeping an eye on available boats just in case and came across this one. 1935 Built Alden Ketch. Victoria City, Victoria

I'm just wondering about the pro's and con's of fiber-glassing a wood boat. Off the top of my head, it would seam that you are adding a lot of weight to the boat while making the hull stronger but perhaps slower.

What kind of things should someone be concerned about with that type of hull?

mitiempo 04-16-2012 12:16 AM

Re: Glassing a old wood hull.
Looks like they did it the right way. They cold molded over the hull to tie everything together, multiple layers I'd guess. Then they glassed over that with epoxy.

Still it is a 77 year old wooden boat.

Capt Len 04-16-2012 12:31 AM

Re: Glassing a old wood hull.
Are stem.keel fastening and wood sound? A classic coastal cruiser for 10 grand ,nothing wrong with slower ,stronger. We're not getting younger either. Unless there is signs of dryrot or delamination of skin ,shouldn't be a big worry It's not an heirloom but could be fun coastal. While you are looking , look at Zeta at the Fort St docks .Ask Bruce on North Star. Make your move,iron is hot.

mitiempo 04-16-2012 01:27 AM

Re: Glassing a old wood hull.

What are they asking for Zita?

Classic30 04-16-2012 04:08 AM

Re: Glassing a old wood hull.

Originally Posted by Agri (Post 859034)
I'm just wondering about the pro's and con's of fiber-glassing a wood boat. Off the top of my head, it would seam that you are adding a lot of weight to the boat while making the hull stronger but perhaps slower.

What kind of things should someone be concerned about with that type of hull?

Just an opinion here from a wooden boat owner, but fibreglassing the hull of an old wooden boat - particularly one 75yrs old - immediately limits it's lifespan. If all you want to do is have fun for a year or 10, that's OK, but the boat is basically doomed in the long term.

Several reasons: Fibreglass doesn't expand and contract like wood fibres do and when the boat "takes up" water from the bilge and elsewhere, heats up in summer and cools down in winter they eventually break away from the inflexible sheath. Any damage to the hull - knocks, bangs, minor collisions, or just hard sailing in rough seas - also allows water through the fibreglass sheath and causes part of it to delaminate. This is fixable, but is a lengthy and very expensive job to do properly. Once a hull is glassed-all-over, it cannot be restored "to original" without replanking the entire hull - again, an expensive task.

People fibreglass-sheath wooden hulls for various reasons, usually because some of the seam were opening and they couldn't be bothered splining or otherwise fixing it properly. If you're serious about this one, you might like to ask them why it was done in the first place. Just because the boat is old isn't a reason to fibreglass the hull.

In any case, if you aren't from a museum planning to put the boat on permanent display on land and if it were me in your shoes, I'd walk away...

mitiempo 04-16-2012 04:25 AM

Re: Glassing a old wood hull.

The boat in question was cold molded over the planking before glassing with epoxy - that is the only way to get it to survive glassing. The Carrs did the same to Curlew about 30+ years ago and she is still going strong.

Of course I have no idea how well it was done.

smurphny 04-16-2012 08:14 AM

Re: Glassing a old wood hull.
Glassing over an old wood hull, if done correctly, is a great idea. I've seen it done to a number of boats. The best way is to sink the boat, if possible, invert it and haul it out upside-down. When it dries out, after mechanically fastening the first layers of glass with s.s. or bronze threaded nails, you essentially build a hull over the old hull. When ribs or planks rot out, you can just throw them over the side. It's an expensive process but there are some old boats out there that you would never be able to identify as having glass hulls.

WanderingStar 04-16-2012 08:40 AM

Re: Glassing a old wood hull.
It's certainly worth looking into. If you decide to proceed, hire a surveyor with experience in wood. Since the work was done twenty years ago, any problems should be apparent. All of my boats have been wooden, one had glass added, she worked fine. You lose very little speed. Relative to the size of the boat, the thin skin increase means almost nothing. It probably didn't lower her one inch, if at all.

Agri 04-16-2012 02:22 PM

Re: Glassing a old wood hull.
Thanks for all the input so far. My main concern would be rot occurring in the cold-molded part of the hull between the old wooden hull on the inside and the glass hull exterior. Having major soft spot problems in my current boat, makes me a little leery of this type of construction. Part of me believes that in theory this is an excellent way to extend, the life of an old boat, and another part says rot.

Found this on another forum that has allayed some of my concerns Cold Mold over Old Carvel Planking.

SloopJonB 04-16-2012 02:47 PM

Re: Glassing a old wood hull.
Simply glassing over a carvel hull has been known for years to be a bad idea - unless you put on so much glass that you essentially have a glass boat with the plug still inside. If not, it apparently only guarantees rot and the demise of the boat. The expansion & contraction of large pieces of wood (planking & frames) eventually overcomes the bond of the skin.

Cold moulding over a carvel hull is another matter entirely - a process wherein the seams are reefed out and splined with softwood and then layers of veneer laminated over the hull produces an extremely strong and long lived boat. It has successfully been done numerous times - locally Jespersons have done it and they are about as good as they come when it comes to wood boats. Obviously it makes for a fairly heavy boat but apparently has little effect on flotation due to the increased buoyancy of the slightly larger hull.

It's no way to BUILD a boat but it's a good way to SAVE a boat that is otherwise beyond economic repair. In these cases, the glass is only a skin, basically for abrasion resistance.

P.S. IIRC, Rod Stephens old "Mustang" was rebuilt this way.

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