Rot Prevention?

SHUG

SHUG

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I have an open wooden boat and the bilges are always wet. Is there anything sensible I can do to inhibit the onset of rot in these wet timbers.
Suggestions so far are
1) Pour a bottle of bleach into the bilges
2) Regularly pour buckets of seawater into the bilges
3) Pour in liquid weedkiller
4) Stop worrying about it!
 
Hi there, I've been wondering the same. My boat has decks and cabin, everyone says it's fresh water lingering in the deck area which causes rot up there, but not to worry about the bilges (there's always a bit of water down there, stern gland drips, rain going down the mast etc)
Have you a particular problem, or are you being ' proactive'? What boat you got? Afloat or ashore, in regular use or not?
I would think twice about bleach, think about your caulking if you have any, bleach might hurt it?
I was thinking about a couple of gallons of Patio Magic tossed down the bilges though, as a preventative measure?
What weedkillers are there, and do they prevent rot? An excellent question.
The so-called experts always recommend regular use and plenty of ventilation, and avoid leaving her with pools of stagnant water.
Keep your limber holes clear, keep the bilges clean to avoid sludge building up in the corners.

Just a few thoughts anyway LD
 
Salt in the bilges will do some good, no harm. No chemicals! When the boat is out and dry give the bilges a good clean and paint. Try to avoid freshwater. Seawater won't hurt too much. Some timbers are more rot resistant than others....
 
ventilation is the greatest enemy of rot... with the odd bucket of seawater in the bildges you'll also help keep the seams tight.
 
Niander said:
Sounds good will also flood the bilges when i go out to sea then pump out.
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Humm, just check your bilge pumps first :-)

Suggest that washing your bilges and boards down whilst in real salty water would help get the protective qualities in salt water in the right places.

If well built the boats timbers will have been selected to resist the detrimental effects of rain water, but then again, as boats age I suggest that softening happens and resistance to rot damage diminishes. In the good ole days of early timber boats the use of bitumen, tar and creosote (old style) used to work well, as the bonding to the timber worked well, sticky stuff.

Suggest an alternative paint to consider is a quality Silver Paint that has the ability to soak into the timber, especially if diluted well before application. Plus additional coats are just over painted because its all the same paint, ie, no bonding probs.

Beware using anything to damage the timbers
 
I seem to remember reading about deck beams with a groove on top filled with salt at the building stage, not sure how long that would last. There must be chemicals that are better, although even TBT has a half life of only 3 months in water. (Bad for the environment, detectable in minute quantities equivalent to one second in 35000 years is one analogy) A FV was laid up in 1939, while the owner went on war work, he coated the inside liberally with linseed oil and covered it over. I've heard of all sorts of oil including used engine oil and paraffin being used. Of course in the old days we had proper tar from the gasworks, lathered on with a blowtorch, but you could never paint over it. Creosote?
 
fisherman said:
I seem to remember reading about deck beams with a groove on top filled with salt at the building stage, not sure how long that would last. There must be chemicals that are better, although even TBT has a half life of only 3 months in water. (Bad for the environment, detectable in minute quantities equivalent to one second in 35000 years is one analogy) A FV was laid up in 1939, while the owner went on war work, he coated the inside liberally with linseed oil and covered it over. I've heard of all sorts of oil including used engine oil and paraffin being used. Of course in the old days we had proper tar from the gasworks, lathered on with a blowtorch, but you could never paint over it. Creosote?
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In a very early incarnation, before my student days, I worked for about 6 months at the Coal Tar Research Association. Coal tar is extremely poisonous and nasty stuff, full of phenols and so on. I'd imagine it is very effective as a preservative - creosote on speed! And, of course, it is thick enough to fill holes very well as a side benefit.

I doubt very much if it would pass today's environmental regulations - some of our routine lab practices in those days (1970/71!) would send the average Safety office white haired in no time. Occasionally I wonder exactly what I was exposed to there - mercury (there was a mercury still in the corner of the lab!), toluene, phenols and asbestos (we wore asbestos gloves to handle hot stuff!) at the very least!
 
There are some who recommend antifreeze. Let the boat dry out then law antifreeze on the planks until it stops soaking it up, this then in theory displaces the water in the wood inhibiting rot and preventing the boat from drying out again since it doesn't evaporate.

Never tried it personally but some swear by it.
 
Woodlouse said:
There are some who recommend antifreeze. Let the boat dry out then law antifreeze on the planks until it stops soaking it up, this then in theory displaces the water in the wood inhibiting rot and preventing the boat from drying out again since it doesn't evaporate.

Never tried it personally but some swear by it.
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The chemistry (at least, with Glycol based antifreeze) is similar to that used to conserve the Mary Rose and other marine relics. However, antifreeze isn't one thing, so I should imagine that different antifreezes will have different effects - up to and including destroying the wood!
 
AntarcticPilot said:
The chemistry (at least, with Glycol based antifreeze) is similar to that used to conserve the Mary Rose and other marine relics. However, antifreeze isn't one thing, so I should imagine that different antifreezes will have different effects - up to and including destroying the wood!
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Glycol based antifreeze is the type to use from what I recall. Your concerns about different antifreezes is a major factor in me not having tried it.
 
I thunk:
a) that the old timers had rock salt placed in their bilges and turns etc so that gatherings of freshwater ceased to be so;
b) my old 'un was soaked in a mix of paraffin and linseed oil;
c) that it was the hydrophilic properties of glycol-based anti-freeze that preserved wooden boats from drying out. Seem to recall that some museum or other had used it on their dry boat exhibits to stop the wood drying and shrinking; it kept the wood at a proper moisture content. Or you could put it on the wood prior to launching to assist in 'taking up'. Not aware of it being used as a preservative in ordinary usage. But then I have forgotten what little chemistry I knew.
 
Poecheng said:
I thunk:
a) that the old timers had rock salt placed in their bilges and turns etc so that gatherings of freshwater ceased to be so;
b) my old 'un was soaked in a mix of paraffin and linseed oil;
c) that it was the hydrophilic properties of glycol-based anti-freeze that preserved wooden boats from drying out. Seem to recall that some museum or other had used it on their dry boat exhibits to stop the wood drying and shrinking; it kept the wood at a proper moisture content. Or you could put it on the wood prior to launching to assist in 'taking up'. Not aware of it being used as a preservative in ordinary usage. But then I have forgotten what little chemistry I knew.
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Poly-ethylene Glycol (PEG) is used for archaeological conservation; it soaks into the timber and deposits a waxy material that supports the cell-structure and prevents further deformation of the timber. It also replaces water, so further drying can't affect the wood. Done right - and there's LOTS of gotchas to take into account, such as sulphur content of the wood and many other things - it is highly effective. Mary Rose and the Vasa are the biggest projects to use this technique.
 
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