Wood rot stopper recommendations.

[fredrussell]

The old mahogany gunwales on my canoe are starting to show the odd spot of rot here and there. Really they need replacing but being a lazy sod if I can get a couple more years out of them by applying some sort of liquid treatment that would be good.

Any recommendations from the wooden boat brigade please?

 

[jasperthedog]

I've used the Ronseal wet wood restorer in the past, seems to do what its supposed to. Dries and hardens the wet bits ready for filler of varnish. Does leave it slightly darker/redder if that matters.

 

[fredrussell]

Cheers, colour change no problem at all.

 

[neil_s]

Another vote for Ronseal - lasts surprisingly well. Shed door still good after 10 years!

 

[jneale]

Use Acetone

 

[Catalina36]

Cuprinol was my choice 50 years ago and for many years after, and it worked for years, but of late it appears to have been dumbed down like everything else the EU got its hands on. The last tin I bought seemed to warn against using it anywhere outside or where rot might be a possibility, or somesuch nonsense.

 

[Stemar]

Just a thought. Is the gunwale structural? I'd have thought it would be on a canoe.

If so, rot might weaken things more than you'd like if you found a bit of rough water. Resin-based rot sealers will make it look OK and are fine for getting a few more years out of a window frame, but will add little or nothing in the way of strength.

 

[jwilson]

I was using some Ronseal hardener last week, on a corner of an old house window cill. AFAIK it is essentially an acetone thinned cellulose type lacquer, and whilst it does harden dry but still spongy-soft wood I don't think it does much at all if wood is actually still wet. The instructions do say to apply to dry wood.

Prymax Wood Hardener 1 ltr I have not yet used, but I'll buy some when I next need more Ronseal. Maintaining a large house buiIt on the cheap in about 1820 means lots of little repairs, and occasional big ones. It claims to be a moisture cured poyurethane which might just harden still-wet wood better that Ronseal.

There are also moisture cured epoxies for rotten wood, but supply seems difficult to find and they're usually expensive. If working on a boat I might try and get some. I certainly wouldn't use Ronseal on anything major or structural on a boat, though a small area of mahogany gunwale might be OK if really dry.

 

[JumbleDuck]

"Git-Rot" penetrating epoxy is good stuff, but like the rest of the Boatlife range seems to be unavailable in the UK now.

 

[Rappey]

I personally think any of these wood rot stoppers are like treating rust with anti rust, it may look great once done but soon comes back with a vengeance.
Cut out the rot/fungus and glue a new bit in.

 

[ghostlymoron]

my brother in law used some Ronsons wood hardener as a temporary bodge on their bedroom window about 40 years ago, they finally replaced it last year so it does what it says on the tin. I used some on the mahogany frame to my companionway where rot had started due to a blocked drain hole - same result. It's wonderful stuff.

 

[fredrussell]

Just a thought. Is the gunwale structural? I'd have thought it would be on a canoe.

If so, rot might weaken things more than you'd like if you found a bit of rough water. Resin-based rot sealers will make it look OK and are fine for getting a few more years out of a window frame, but will add little or nothing in the way of strength.

Gunwales are very much structural on a canoe Stemar, but luckily all the rot on mine is at the bow and stern areas where the gunwales are of little structural importance, the (Kevlar) canoe being very stiff there.