Rot repair

[White_Lady]

I have aquired an old Mirror 'Marauder' sailing dinghy.It is constructed of plywood.Parts of the floor have some rotten areas.
I have seen on the net a couple of products that suggest you can stop the ror and repair existing damage.These products are 'Rot Fix' and 'End Rot'.
Anybody used these ,or shall i replace the ply. ( rather repair if poss )

Many thanks

Sinking of Cheshire /forums/images/graemlins/confused.gif

 

[Mirelle]

Replace the ply.

It is not as much work as you think, and if I recall this design right it is a stressed skin type, so replacement to original strength will be better.

And it won't cost much more, either.

 

[Lakesailor]

I repaired my Heron by replacing the floor where it was shot. It's not just the veneers in the ply that are shot, but the adhesive between the veneers. The hardwood frames in my boat were a bit wooly in plces and I replaced those and had to refix all the frame joints. As the boat was well dried out I used epoxy resin, which soaks into the wood and creates a fantastic bond.

See the repair here.

and the finished job at www.lakelandimages.co.uk/Heron/index.htm

Good luck.

 

[Captain Coochie]

The rule of thumb is to replace all timbers 1m past the last sign of rot infection . Trying that rule on a boat is a worrying thought .
Id suggest cutting out the rot and treating the surrounding areas with industrial rot killers rather than a product called stop rot . If you dont want to pay for the pros to treat the rot Cuprinol 5 star rot treatment is the closest ive seen to the industrial stuff .
Do you know what kind of rot you have ? Dry rot , wet rot , or is it the rot that looks like old expanding foam ?
What the hell is that rot that looks like old expanding foam ? It seems to have no feeder strands just a fruiting body /forums/images/graemlins/confused.gif

 

[ccscott49]

Cut it out and replace, no other real way of doing it.

 

[oldharry]

Forget 'miracle cures' like these - if they worked there would be hundreds of eldely wooden boats swanning round in 'as new' condition!

The theory is fine - impregnate the rotten timbers with a chemical which then sets hard and restores the strength.

In practice it is impossible to get sufficient material into the rotten timber to work, other than in laboratory controlled condtions. In practice the material penetrates usually around a few mm depth, forming a skin over the rotten timber, and appears sound, but with no real strength. Maybe OK for home window frames to fool the new purchaser, but definitely not for anything that is loaded or stressed in any way.

Plywood alsohas a specific problem wth these materials: it is usually impossible to get the material past the veneer glue joins and in to the inner veneers, so again although the panel may LOOK sound, it is actually still very weak.

Repairing a plywood dinghy neatly is much easier than doing its GRP counterpart.

 

[White_Lady]

Thanks all for the advice. I shall post a picture when she is re-planked!

Thanks again

Phil