Dealing with Mold and Rot inside a Wood Hull

[VKRUE]

Hey.... TheSound..........

Are you still here ?

I really like your boat's lines... nice looking craft.

Any recent photos of her ? Her interior ?

Hope to see a lot more of her here.

[VKRUE]

Hey TheSound:

Are you out there ?

I don't know why but, last night when I checked your profile for other posts by you, it only came up with these post here on this thread... and naturally, I thought that you were new to the forum.... My appologies, I am mistaken...

Today I see that you've asked several questions regarding your boat, and been given a great deal of good information.

So how did your boat fare this past winter ?
What did you do to weather proof it for storage ?
Have you made the new rudder yet ?
Sooooo many questions....... huh !

[roseandpaul]

Can anyone please tell me if the glycol is ordinary antifreeze, concentrated antifreeze or PEG 1000? I understand that PEG will leave a waxy surface which would not be ideal to paint over. Also, can the solution be applied to the interior of a marine ply Dynel sheathed boat without causing problems with the Dynel and epoxy lifting off the outside of the hull? Any experience of using this treatment would be much appreciated.

roseandpaul (and Minx II)

[TerryKing]

Originally Posted by roseandpaul

Can anyone please tell me if the glycol is ordinary antifreeze, concentrated antifreeze or PEG 1000? ..(snip)..

RoseAndPaul, take a look at:
http://www.boatdesign.net/wiki/Mater..._DETERIORATION

on the Wiki(beta) which covers some of the information on this.

Most people I know of have used straight undiluted Ethylene Glycol as it is sold as automotive antifreeze. The dye in it is quite diluted and doesn't seem to show later.

PEG (PolyEthyleneGlycol) seems to be NOT toxic or effective (see Wiki)..

You will get a variety of opinions. My personal experience is that applying Ethylene Glycol to areas of my 28-year-old boat that appeared to have mold and rot appearing was very effective. It apparently will diffuse into the wood, and will need to be reapplied (I do it Spring and Fall, and nothing seems to be growing in those areas at all.

I have mahogany frames, marine plywood, with glass/epoxy on the outside. I have not seen any delamination of the outside.

Use gloves, eye protection, be careful, be safe. Don't leave any liquid that an animal could get at. (Paper towels, wipe-up, in plastic bag in trash can for me...)

Let us know your short and long-term experience, so we all keep learning!

[roseandpaul]

Thanks for the feedback Terry! I have found some antifreeze with "33% ethylene glycol"* and I am supposing that if I boil this up with the borax and boracic acid powder I should be able to boil off most of the water anyway. I am a trained health and safety rep for work so safe practices will be very much to the fore! I am intending to strip off all the interior paint and give all the timber a really good soaking with the preservative and then repaint when it is dry. I am also going to soak all surfaces of the new decking before fixing and then apply a fairly heavy fibreglass above and a slightly lighter weight below and epoxy over. If you know any reason why this would not work, please let me know!

Rose.
* couldn't find anything here that was 100% ethylene glycol - the labels on the concentrated antifreeze do not specify content at all.

[TerryKing]

RoseAndPaul: Better check this out from the Wiki:
---------------------( COPY )--------------------------
Paint and Epoxy Adhesion VS Preservative Treatments

Tests by West System on adhesion of Epoxy on wood treated with Ethylene Glycol and Ethylene Glycol - Borate: http://www.maritime.org/conf/conf-reynolds-mat2.htm <<< Read this for proportions <<<

Synopsis: strong (75-25%) Ethylene Glycol - Borate treatment affects adhesion badly. Less strong solutions and Ethylene Glycol alone do not significantly affect adhesion.

Backup Location: http://terryking.us/boatbuilding/Eth...S-Adhesion.pdf

Dave Parnell on Paint/Epoxy VS Ethylene Glycol treatments (quote): Once the wood (treated with Ethylene Glycol alone) feels dry to the touch, then paint, epoxy and glues work fine. Borates interfere with paint, epoxy and glues.
-----------------( END COPY )----------------------

Adding the borate makes the protection very long-term but does affect paint and epoxy adhesion.

I've never had trouble finding 'straight' Ethylene Glycol antifreeze. The 50% and 33% versions are cheaper 'ready to use in the radiator' versions. The 100% (maybe not labelled that) should be more expensive (say $6 a gallon) and noticeably syrup-like in consistency. Most good auto parts stores would know the difference...

But: The West tests imply that 50% Glycol 50% water has almost no effect on adhesion.

[roseandpaul]

Terry, Thanks for your eagle eye! I am getting more confused by the minute - can't get onto your web site at the moment - it seems to be down. I will try again later and try the local automotive parts people again.

Rose.

[robert_mercer]

Very interesting article about glycol.

Is pressure treated wood a better start when replacing wood?

How is oil based paint adhesion to glycol treated wood?

Robert

[The copper guy]

VENTILATION!!!!!!
On any boat the natural draft is from aft to for ad.
When closing the boat up for extended periods.
Lift the cabin sole,
Open all locker"s and drawers hook all doors OPEN.
Arrange some kind of air catcher on lasarett or point the dorade into the wind.
On the bow preferably the chain locker arrange an extractor or point the dorade away from the wind, (small solar driven fans actually work well as they run in the day when it is going to be warm below)
It is a simple mater to revers them BLOW/SUCK.
In addition when hauled out scrub/wash/clean and allow to dry.
If she is drying out to fast or a week before splashing her.
Mix 1/3d boiled linseed oil 1/3d coop renal (wood preserver) 1/3d Lamp oil in a garden sprayer and try to get as much of the inside hull as possible,
Any excess will go in the bilge and hopefully will get sucked into the wood.
When you go back in the water she will not take any water!!