Waterproofing an old wooden sailboat with epoxy or fibreglass

[Schooner Chandlery]

Well, interesting. A wood boat in need of a a lot of fixing up often needs refastening of the planking to the frames as a first step. After having done that, cotton recaulking and/or tightening up the existing cotton caulking and seam compound might be all that's needed. More traditional materials, easy processes to follow that even I can do.

This is all said because if it's an old wood boat that's been in and out (and in and out) of the water for decades and decades it might have sufficient crushing of adjacent planks that you're going to have a big fat seam to fill--with something like an ordinary seam compound. No fancy epoxies really needed. The boat weeps from the seams if there's been a good deal of movement of planks because of the need to refasten or deal with cracked frames (ribs) or some other structural issue that a soak with epoxy isn't going to take care of. Deal with the mechanical issue of the fasteners and the cotton caulking and traditional seam compound and you're done. For the next 20-30 years.

If the planks are weeping with water soaking through the wood rather than the seams, just go ahead and run screaming because it's likely not the boat for you unless you'd like to replank it. Replanking is a viable option for some folks--even those with no prior planking experience--but you're likely to find a better boat that is not quite so "needy" if you just keep a lookout for one.

If you happen to replank, then by all means, get something like Smith's Clear Penetrating Epoxy Sealer to paint onto the new planks as that materials will help the planks stay more stable and soak less water. You only want to do this if you're replanking and your wood is new because you'll adjust the outgauge between the planks to be a bit tighter since you're, in theory, removing the wood's ability to soak quite so much water up. That's in theory. If you are not replanking and the boat doesn't have rot, then, in my opinion, don't bother with the epoxies. Just do what wood boat owners have always done with traditional materials and you'll be fine.

Here's me caulking our newly planked 81 year old boat. If I can do it, it's not that hard and not much reason to go with modern materials that probably won't perform on your old wood boat nearly as well as the original materials do.

[Wotname]

Originally Posted by Schooner Chandlery

Well, interesting. A wood boat in need of a a lot of fixing up often needs refastening of the planking to the frames as a first step. After having done that, cotton recaulking and/or tightening up the existing cotton caulking and seam compound might be all that's needed. More traditional materials, easy processes to follow that even I can do.

This is all said because if it's an old wood boat that's been in and out (and in and out) of the water for decades and decades it might have sufficient crushing of adjacent planks that you're going to have a big fat seam to fill--with something like an ordinary seam compound. No fancy epoxies really needed. The boat weeps from the seams if there's been a good deal of movement of planks because of the need to refasten or deal with cracked frames (ribs) or some other structural issue that a soak with epoxy isn't going to take care of. Deal with the mechanical issue of the fasteners and the cotton caulking and traditional seam compound and you're done. For the next 20-30 years.

If the planks are weeping with water soaking through the wood rather than the seams, just go ahead and run screaming because it's likely not the boat for you unless you'd like to replank it. Replanking is a viable option for some folks--even those with no prior planking experience--but you're likely to find a better boat that is not quite so "needy" if you just keep a lookout for one.

If you happen to replank, then by all means, get something like Smith's Clear Penetrating Epoxy Sealer to paint onto the new planks as that materials will help the planks stay more stable and soak less water. You only want to do this if you're replanking and your wood is new because you'll adjust the outgauge between the planks to be a bit tighter since you're, in theory, removing the wood's ability to soak quite so much water up. That's in theory. If you are not replanking and the boat doesn't have rot, then, in my opinion, don't bother with the epoxies. Just do what wood boat owners have always done with traditional materials and you'll be fine.

Here's me caulking our newly planked 81 year old boat. If I can do it, it's not that hard and not much reason to go with modern materials that probably won't perform on your old wood boat nearly as well as the original materials do.

Ahh... the picture reminds me of caulking a much smaller (28') boat decades ago - it was a labour of love.

I think the big problem with applying modern plastics (epoxy & polyester etc) to old wooden boats is that it is done to "cheaply rebirth" a dying hull.

Doing anything on the cheap on any boat usually ends in tears and doing it cheap on a run down unmaintained boat always ends badly (IMO).

I'm reminded of the adage "if you can't afford to do it right the first time, when will you be able to afford it".

So yes, splashing some poly resin around on an old poor hull may get you an extra 5 or 10 years, after that the hull will be terminal - IMO .

Disclaimer: I have epoxy coated an old (40+ years) plywood 30' hull (inside and out with glass below the waterline and on the decks) but the hull, topsides and superstructure were all in tip top condition before the first brush of epoxy was applied. 10 years on, it is still all good. The epoxy was applied in ordered to reduce ongoing yearly maintenance of the plywood and the process appears to be successful.

[TrentePieds]

Earthmover:


You say you own a Challenger 24 - a nice little boat that should keep you happily cruising The Lakes for the rest of your life. So what's your motivation for wanting to go down a road at the end of which lies perdition?



Are you hoping to get a bigger boat for cheap, or have you fallen in love with “a classic” that “needs rescuing”? It seems to me that there can be no other motivations for doing what you are proposing. If it's a bigger boat you want, then I'm sure that in the fall, for ten grand, you'll be able to take, say, thirty feet of “frozen snot” off the hands of someone who has become disenchanted with the expenses of boat keeping. And you'll be sailing rather than sanding, slinging goop and cursing.


Where is the percentage in what you are proposing?

This whole thread has been one long warning against doing it. Warnings uttered by sailors who “have seen the elephant”!


But for the edymication of newbies and lurkers who float onto and off this forum without our necessarily knowing anything about it, do tell us what you motivation is. Your doing so might spare someone a lot of grief!


Remember that wooden boats, particularly when they are “sheathed”, are on life support from the day they are launched. Frozen snot boats never die. They have to be euthanized with a chainsaw :-)!


TP

[NevisDog]

Originally Posted by TrentePieds

Remember that wooden boats, particularly when they are “sheathed”, are on life support from the day they are launched. Frozen snot boats never die. They have to be euthanized with a chainsaw :-)!

I finally figured what "frozen snot" means - so true, at least the early ones! Someone else put it thus: polyester boats will still be around when the earth falls into the sun. The big flaw I guess is the balsa, or timber, or ply used in the fit-out, but the hulls remain forever.

[crazyoldboatguy]

I would't try it with an old hull. In order for the wood to remain stable it must be sealed on both sides. Not possible with the planks already fastened - unless you remove them for treatment.

I am restoring a 70 year old 47 foot Alden designed ketch. I had initially thought of the Vaitses method mentioned earlier - mechanically fastening partly cured first layers of glass followed by more layers of glass. In the end decided to replank the entire boat.

Each plank was sealed with 3 coats of CPES, inside and out. Each plank in a row have been glue scarfed to the other - no butt blocks. Each row of planks are glued/splined to the adjacent rows. The exterior of the hull will be covered in multiple layers of Interlux 2000e (6 coats below the water line).

Wouldn't consider this strategy unless the planks are removed, sealed and refastened (and eliminating butt blocks and seams). Or, as in my case, new planks treated to prevent any ingress of water - as in a cold molded vessel.

In either case it is a huge investment of time and money - I can assure you of that.

[Cadence]

Originally Posted by crazyoldboatguy

I would't try it with an old hull. In order for the wood to remain stable it must be sealed on both sides. Not possible with the planks already fastened - unless you remove them for treatment.

I am restoring a 70 year old 47 foot Alden designed ketch. I had initially thought of the Vaitses method mentioned earlier - mechanically fastening partly cured first layers of glass followed by more layers of glass. In the end decided to replank the entire boat.

Each plank was sealed with 3 coats of CPES, inside and out. Each plank in a row have been glue scarfed to the other - no butt blocks. Each row of planks are glued/splined to the adjacent rows. The exterior of the hull will be covered in multiple layers of Interlux 2000e (6 coats below the water line).

Wouldn't consider this strategy unless the planks are removed, sealed and refastened (and eliminating butt blocks and seams). Or, as in my case, new planks treated to prevent any ingress of water - as in a cold molded vessel.

In either case it is a huge investment of time and money - I can assure you of that.

Sounds as if you are doing a hell of a good job not a patch. She should be good for the next 100 yrs..

[softdown]

When I was a kid I watched my dad and a friend cover the bottom of an old wooden boat with a sheet of fiberglass and resin. I refinished the boat twice over the ensuing years and used it...twice. The fiberglass kept everything water tight except for one corner where a gap developed.

I thought bailing water added to the excitement. Dad and brother disagreed with that assessment. Hence....I used it twice.

The boat lasted another fifty years after the fiberglass was laid on the bottom. That was with the boat stored upside down. If I had known enough to repair the leaky corner....who knows how much service it would have provided. Not many want to be seen in an old $500 boat when others spend $100,000 for a water skiing boat.