Wooden coachroof leaks

noswellplease

noswellplease

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I discovered a small corner section about 2 inch in length and 1/2 inch high had perished due to water damage and was now rotten, the rest of the coachroof appears to be fine. I was wondering what new fangled material might be best to fill the void. I could try and mould something out of marine ply but I don't think it would be very effective long term. Would GRP do the business or is there something else which might work better. Unsure hence the question. The boat is 40 years old so its hardly surprising to find something like this I guess.
Suggestions much appreciated. Thanks.
 
LittleShip said:
Apparently, and contrary to popular belief...... they still produce it although it can sometimes be expensive ??

As stated the only true way to repair it is to use wood.

Epoxy with matting on top is the best way to seal it.

Tom
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You can seal wood too much though. Best to just use paint, varnish and oil that won't completely stop the air getting to the wood. Well kept like that a wooden boat will easily last 100 years. No epoxy build has yet reached that age so no one knows what'll happen in the long term.
 
I guess one can alway try to achieve a good replacement timber section which would hopefully fit nicely and do the job, but are we talking aspirationally here? Is the whole thing gummed in with copious amounts of wood glue and fingers kept crossed. How long is the glue good for and what then?
I had thought of covering the whole coachroof (which incidentally was painted white by a previous owner) with gpr and matting but would this not take from the elegance of the coachroof and basically make a dogs dinner of it. I'm inclined to think that the best way is a wooden wedge glued in followed by varnish and paint on top. Thanks for the suggestions!
 
To get a shipwright to scarfe a small piece in to the rotten area should not break the bank, and if he's worth paying for then the repair should blend in well and last as long as the coachroof as a whole. I'm afraid to say that in my opinion glass matting has no place on a wooden boat, it's only ever a last resort and a road that once started, will only cost far more in the long run.
 
Woodlouse said:
You can seal wood too much though. Best to just use paint, varnish and oil that won't completely stop the air getting to the wood. Well kept like that a wooden boat will easily last 100 years. No epoxy build has yet reached that age so no one knows what'll happen in the long term.
Click to expand...

History

The first commercial attempts to prepare resins from epichlorohydrin were made in 1927 in the United States. Credit for the first synthesis of bisphenol-A-based epoxy resins is shared by Dr. Pierre Castan of Switzerland and Dr. S.O. Greenlee of the United States in 1936. Dr. Castan's work was licensed by Ciba, Ltd. of Switzerland, which went on to become one of the three major epoxy resin producers worldwide. Ciba's epoxy business was spun off and later sold in the late 1990s and is now the advanced materials business unit of Huntsman Corporation of the United States. Dr. Greenlee's work was for the firm of Devoe-Reynolds of the United States. Devoe-Reynolds, which was active in the early days of the epoxy resin industry, was sold to Shell Chemical (now Hexion, formerly Resolution Polymers and others).
 
Poly resins do stick to timber long term so you need an epoxy resin.

You could mix a small batch (one egg cup) add the hardener and paint the area to prep the timber, then add some micro balloons to the mix and part full void; finish off with a small strip of timber to cover the area and retain the look, just tape it place till the resin cures.
 
noswellplease said:
I guess one can alway try to achieve a good replacement timber section which would hopefully fit nicely and do the job, but are we talking aspirationally here?
Click to expand...

In my experience as a complete novice, repairing the wood by cutting out the rot and fitting in a new piece was much easier than I thought it would be. Certainly not something to be considered only as an aspirational ideal, it was very much as a straightforward realistic solution.

Chris
 
oldsaltoz said:
Poly resins do stick to timber long term so you need an epoxy resin.

You could mix a small batch (one egg cup) add the hardener and paint the area to prep the timber, then add some micro balloons to the mix and part full void; finish off with a small strip of timber to cover the area and retain the look, just tape it place till the resin cures.
Click to expand...

"I think you ment to say dont stick long term."

Ok short answer

Poly resins do stick to wood but will over time release, the bond that a poly resin has is just by "sticking" to the top layer of the wood.

Epoxy on the other hand, bonds by soaking into the wood and therefore forms a very strong impermeable seal and prevents any ingress of moisture. It's more of a chemical bond.

Epoxy is a great sealer and glue on wood boats and most if not all of the classic boat builders use epoxy.

Tom
 
LittleShip said:
"I think you ment to say dont stick long term."

Ok short answer

Poly resins do stick to wood but will over time release, the bond that a poly resin has is just by "sticking" to the top layer of the wood.

Epoxy on the other hand, bonds by soaking into the wood and therefore forms a very strong impermeable seal and prevents any ingress of moisture. It's more of a chemical bond.

Epoxy is a great sealer and glue on wood boats and most if not all of the classic boat builders use epoxy.

Tom
Click to expand...

Thanks Tom, you are right I did miss the word NOT.
 
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