Rotting Wood

[mat]

Is rotten wood like rust or cancer? If the water exposure is stopped does the rot continue? Will epoxy bond to rotten wood?

I think I know the answer but that will require extra work! Is there any chemotherapy available? :(

[HappyHammer]

I'm no expert mat but I think the real problems start when the moisture goes away and the rot becomes dry rot which can travel quite extensively, through wood and brick. Another problem is that it will attract Termites which are worse than dry rot.

HH.

[John Kinnane]

mat, as I understand it wood rot is caused by a fungus and it needs two things to happen, food (wood) & moisture. You need to remove any pulpy soggy wood and treat surrounding area.A heat gun used around suspect area will help kill remaining fungus (also anti freeze will kill it-as posted here in previous discussion).I am in the middle of repairing a Hartley 16' plywood trailer (link here for photos)
http://s8.invisionfree.com/Trailer_Sailers_Oz/index.php?showtopic=3
I have repaired two spots in cabin structure and currently cleaning up inside boat prior to treatment. After all soggy wood ie removed I will treat all bare ares with a penetrating preservative epoxy (Norglas). This is a 1:1 mix and very thin, followed by a two coats of BoteCote 2:1 epoxy mix. All suspect seems and joins will then have an epoxy putty fillet. Also any holes dug into the wood will be filled with epoxy putty. Where you cut plywood out it is easy to replace with new epoxied ply inserts.

[Daddles]

The scary part about rot is where it happens. I've just stripped on old plywood boat. It was last done by the previoius owner about 4 years ago. He gave me photos from that time and there are black spots on the wood in the photos. When I stripped it, I found some wet, black spots and some out and out rot in some corners - hit with the heat gun and left out in the summer sun for a week and it seemed to come good. I'll find out in another four years won't I :( . The thin epoxy, and there are a few of these around, is a good move. There is a company here in Adelaide that makes one they call timber preservative. I couldn't afford it for my little boat unfortunately (just one extra cost in an already overly long list, none of which I could afford in the first place :mad: ).

The scariest part was pulling off a strip of fibreglass tape and getting a very strong musty smell :eek: That was an experience that put me off glass sheathing an old boat and makes me wonder about doing it to a new one.

Cheers
Richard

[STEPHEN MILLER]

Richrd :)
Blackspots and staining household bleach does wonders leave bleach on area for a whilethan rinse well afterwards. All rotten wood must be removed before using epoxy but once its epoxied well it should keep the water out. Water can get behind sheathing if not attached properly or through defects in ply or if boat had water in hull for long time can getin from opposite side.

Steve

[John Kinnane]

Last night while I was getting ready to patch the small hole in the bottom ply (adjacent to the keel) I started to dig a little further. Finding more soft wood I went and got the cordless drill with about a 12mm bit and proceeded to drill holes into the keel from the transom to the centre board case. Then up the road for some anti-freeze which I applied by funnel into all the holes and a lot ran all along the keel to the bow. This morning I drilled a few more holes and gave it some more AF. I'll keep you posted on the results.

[malcolmdaniel]

Is rotten wood like rust or cancer? If the water exposure is stopped does the rot continue? Will epoxy bond to rotten wood?

I think I know the answer but that will require extra work! Is there any chemotherapy available? :(

Theres 3 types of rot (as in classifications of fungis) and they are different

Identify 3 Types of Wood Rot (https://www.majorpaintingco.com/projects-and-tips/identify-3-types-of-wood-rot#:~:text=The%20most%20common%20types%20of,white%20rot%2C%20and%20soft%20rot).

wet rot i think is soft rot that destroys lignin in wood - it usually stops when water source is taken away

brown /dry rot destroys cellulose in wood and needs alot less moisture and doesnt seem need water source as in hole or leaking pipe etc and so is hard to spot and get out completely

Everyone says cut out rot plus another 50 - 100 mm

Ive got rot in my plywood in cockpit . Ive cut most out but theres couple spots i cant or unwilling cut out and trying find suitable fungicide to use. I was going use boric acid till i found out it leaches out with water and probably may kill the rot on or near surface initially isnt suitable for boats permanently thou.
The other choice is a NZ made metalex (copper napthanate ) but they recommend using turps solvent as a carry agent at 2 parts metalex to 3 parts turps which must leave oily surface and unsuitable for gluing and painting. Im considering using it with meths or two way thinners

[b.o.a.t.]

this might be a bit late for you, but....
Chemo Therapy for Rot - Dave Carnell (simplicityboats.com) (https://www.simplicityboats.com/chemorot.html)
Dave would be on the high side of 100 y/o if he's still going - a long-retired chemical engineer when he wrote the article over 20 years ago.
Have tried antifreeze on toenails - works well at killing athletes foot. One dab per fortnight until the nail grows out.
Have used it as a wood preserver - worked well almost 20 years - Tas Oak in ground. Until the termites found it...

possible negative - breaks down into an acidic compound.

Seemed to work on plywood surface infections for 3 or 4 years before I sold the boat/s.
Never used it to kill deep rot so can't speak for long term effectiveness for that.
Have always cut & replace badly affected timber.

[jack620]

this might be a bit late for you, but....


19 years later! :)

[b.o.a.t.]

Sept '23 update / query.
But yes, I've been away from these fora for a few years...

[Hoey]

My neighbour told me about this product from Bunnings called Earl's wood hardener that can stop rot . I have not use it myself :)

[b.o.a.t.]

where wood is rotten, it's gotta go.
Can't restore strength to something which is no longer wood.
surface blemishes & traces... probably / might be able to kill it. Or not...
Whether you take the chance depends on consequences if you fail I guess.