wetwood

[chrishelen]

Hi
my boat is an Eventide 24 built of ply in 1986, i belive the decks at least are covered in cascover? she is my first wooden boat having owned a few plastic ones in the past. I have a bit of a problem with a small patch on the foredeck. it looks like a mooring rope has jumped out of the fairlead and chaffed a small hole in the covering and water has got into the wood, i have removed about a foot square of the cascover?and covered the area until the wood dried out but there is a soft springy area about six inch square just behind the fairlead, the rest of the foredeck feels sound, how can i repair this without resorting to replacing the front triangle of deck?and if the wood is marine ply why has it rotted?
, thanks in advance, Chris

 

[reiner]

Marine ply is not nessecarily rot resitant. If its penetrated by freshwater which canot evaporate because of the cascover, for example, it deteriorates same as its natural counterpart, especially in warm climates. The trick is to prevent water from penetrating by sealing the edges. You can probably
scarf in a fresh piece of ply after removing the soft spot, using epoxy resin and I would double it up from downbelow if possible.

 

[chrishelen]

Hi thanks for that, would i just scrape the old ply out until i come to dry hard wood, or cut the whole section out.

 

[burgundyben]

I'd drill your self a series of small (1/8th inch) holes around the area that is soft, go to about half depth into the wood, buy some disposable syringes (back of a 7 series BMW in a council estate or local chandlery) squire a warm epoxy mix into all the holes, then coat area with epoxy by brush.

 

[Guest]

Get rid of all the rotten wood, and chop out a bit further back than that to ensure you have left nothing that might re-start it. then let in your new piece, and has been already said, double up from below. Either use a good waterproof recoursanol glue or epoxy, to fix the new piece.

 

[oldharry]

http://www.eventides.org.uk/ There is gigabytes of pics, information, stories, advice etc about Eventides.

Marine ply is still wood, and will rot. It seems rain water is particularly evil for some reason, and if it can stand and soak in to marine ply it will rot very quickly. The thin sections of the veneers seem to hold water better than solid timber.

There are 2 ways of replacing small sections of ply, depending on your skill as a carpenter. The first thing is to cut back to sound wood and about 6 inches beyond. Soak everything in Cuprinol anti rot to kill any rot spores.

Square up the resulting hole to a manageable shape. Now: to make an 'invisible' repair (the more difficult way) you effectively scarph the new ply to the old, by chamfering the edges of the hole and the new ply by at least 3 times the thickness of the ply. When you have a good fit, glue the new piece in place. I once watched a professional boat builder do this: he took great pains to ensure the chamfered edges matched exactly, and the end result was - invisible. except for the change in the grain pattern. Beautiful!

The easier way is to shape the new ply to the hole as precisely as you can, put a backing piece over the inside overlapping by at least 50mm (75mm for a larger area), then glue the new insert into place, taking great care to ensure the edges are well protected by glue. You need a 'gap filling' glue such as epoxy for this. It is essential that water can not penetrate the gap between the patch and the old timber. If it does, you will be starting all over again in a year or so!

The repair can then be sanded down, and whatever protective layers you want can be rebuilt.

If the deck is sheathed then you again have to make sure that the joint in the sheathing is completely watertight, and remains so. Not very easy, and this is the biggest drawback of a sheathed ply boat. I know, my Eventide 26 is Cascovered too!

 

[dur]

An alternative hidden joint method, if you have room around the patch, is to cut back to good and then use a router to make a half lap joint on the deck and a correspoding lap on the patching piece. Then the warm epoxy etc etc as previously mentioned. But if the inside is hidden, stay with the backing piece - quicker and stronger. Be prepared to have to cut a long way back to remove any wet ply. It is likely to be wet much further than the area of rot and the all the wet has to be removed.

 

[chrishelen]

Thanks for that, im not to good at carpenty just yet but im learning fast, the trick with the router sounds good,soon as the rain stops, about june i`ll give it a bash,
chris.

 

[Guest]

You aint in Vellator are you?

 

[chrishelen]

Thats a no.

 

[chrishelen]

Do you mean valleta?

 

[Guest]

Nope, I mean Vellator, in Braunton N. Devon. /forums/images/graemlins/smile.gif

 

[chrishelen]

Never heard of it,sorry