Is antifouling a waste of time?

andybussell

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After haul-out I looked at the base of my boat's keel today. There was a small rectangular patch with no antifoul, no barnacles, no mud adhering (I'm in a mud tidal berth) - just smooth epoxy. Everywhere else the opposite was true - antifoul with mud sticking like concrete and liberally scattered barnacles.
The clear patch was where the chocks had been when antifouling a year ago - because of this the patch only received a slap of antifoul immediately before launching. I have to ask, is the care I was taking for most of the boat a waste of time (and money)? Anyone else with similar experience?
 
Try a year without AF and see.
I'm in all year and I AF about every 5 years.
The fouling is negligible, mainly because the mooring is on a river, so the hull gets fresh'ish water on the ebb and salt'ish water on the flow.
I dry out around May and clean the hull.
I am thinking of switching from AF to silk finish emulsion - so many more colours to choose from.
/forums/images/graemlins/laugh.gif
 
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Its cheaper than epoxy

[/ QUOTE ] Antifouling paint is no substitute for epoxy what so ever.

Epoxy coatings can be used to protect a GRP hull from osmosis or in the repair of a hull affected by osmosis.

Antifouling offers no protection against osmosis at all. All it does is prevent fouling if you are lucky.

Is antifouling a wate of time.? Less of a waste of time than a mid-season scrub when you could be out sailing IMHO.
 
I know how you feel. I have a 37 ft cat which is on a drying pontoon in Fareham. Last year I dried out on the slipway mid season and scrubbed because the bottom was about 1/4 inch thick with barnacles. That's having used cruiser-uno last spring. When I scrubbed I didn't anti-foul again and have just dried out on the slip again expecting to be smothered. It wasn't! There were barnacles on the bottom of the bilge but not too many. However, in both cases there were none on the keels. I think one answer is grinding up and down in the mud each tide takes them off the keels but not off the hull. Might be part of the answer for you too. Next winter I will haul out and use something else but I have not decided what yet.....
 
I'm river based so fresh water. I can't afford to have the boat lifted etc every year and I follow what the Norfolk boatyard foreman who sold her to me said, "just do the bit the sunlight reaches so it looks pretty at the waterline". For the last 4 1/2 years I haven't even done that but lifted her a couple of years ago to clear a fouled prop to discover a black slime over the hull only, wiped of on my hand, nothing growing at all and about 6 small shellfish around 6mm across. Admitedly the waterline is disgusting where old a/f has peeled or got scraped off but no fouling.

My conclusion based on this is that a/f on the Thames, at least for me, is a money maker for boatyards or hard and unecessary work and expense for me and for purely cosmetic reasons I would only ever need to paint the bit at waterline.

On my previous boat on the Great Ouse (fresh water tidal) the same applied. My current boat is (old) GRP, the previous was (old) dutch steel.
 
I thought that as well, plus the idea that the single coat of antifoul put onto the patch just before launch did its job well, but had eroded away shortly before lift out.
 
Went to a lecture once when we were told that 95% of fouling starts from about now until beginning of May-ie the"young" take hold.
I'm therefore trying a new tack this year. Boat been in all winter. Will lift early June for a week to scrub and antifoul and test the theory. Not much on at present! Pressure washed last October.
 
Your lecturer clearly hadn't been to Poole or Keyhaven where we get more fouling than a cunning fox with a foul cunning plan. Both are shallow warm basins that act as accelerators for growth. We aim to scrub and put at least one coat on every spring with a complete scape off and double coat every three years or so.

Not too much growth during the winter but come from about now on it grows amd boy does it grow usually needing a scrub late June and another late August.

By way of comparison, 2 seasons in Norway needed one scrub to remove slime at the beginning of the second season.
 
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Went to a lecture once when we were told that 95% of fouling starts from about now until beginning of May-ie the"young" take hold.

[/ QUOTE ]

That explains why so many people round here don't launch until June /forums/images/graemlins/grin.gif
 
[ QUOTE ]
Went to a lecture once when we were told that 95% of fouling starts from about now until beginning of May-ie the"young" take hold.......

[/ QUOTE ]
A common story and seems an old wives' tale at least where we are (mud berth North Kent). We scrub in July/August, and we have new young barnacles attached again by the time we lift out.
 
I have not antifouled my Chichester based bilge keeler for over ten years. This saves me a great deal of time effort and money. The downside is that once a summer I have to dry out on a sand bank and it sometimes takes me as much as half an hour with the back of a broom to scrub the hull. I do however give it a pressure wash when I haul out in the winter.
 
Barnacles spawn twice a year, as far as I am aware. Although the green stuff grows all year round. Also if the water is clearer, then more sunlight can get through to your hull which makes a difference.

I don't intend to antifoul. I tend to scrub a couple of times a year, although I have a 21' bilge keeler so it's not exactly time consuming. Done straight from wet it's OK...
 
A professional anti foul job costs me NZ$1700 every 2 years (i know I'm lazy but it is worth it to me) and I have a lift and pressure wash (NZ$75) maybe twice in that time. Total NZ$1850.

Or I can get a diver to give her bum a wipe every month at NZ$ 50 a pop - x24 = NZ$ 1200.

I'm seriously thinking of forgoing the biannual antifoul charade.
 
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