Antifouling

[Bruce]

I'm thinking of doing my own antifouling this year and I've got a few questions.

How many litres of antifoul does it take to do two coats on a TH?

The boat was last antifouled in May last year. In October the boat was out of the water for an engine repair and I cleaned the hull while it was out. So it has been about 10 months since it was last cleaned, 15 months since two coats of 'Micron Extra' were applied. I'm noticing the boat getting slower. Is this timeframe normal for time between antifouling? Should it last longer or is that about normal?

Is it cost effective to do it yourself? Planning to slip it at Fenwicks. Slipping and hardstand charges would be about $500. I paid $1100 last time to have it done for me at Holmeport Marina.

I'm mainly thinking of doing it myself as I want to paint the hull above the waterline and remove a few osmosis blisters as well and I figure if it's going to be out of the water, I may as well do the lot myself, but I might be about to subject myself to a whole lot of pain. Any thoughts appreciated.

[Troppo]

I used a 4 litre tin on mine. Also ended up needing 2 litres of primer.

Don't know if it is cost effective. Had unseasonal rain start falling on the day I had Windchaser pulled up on the slip. That delayed the start of painting for nearly a week which meant extra costs from time on the slip. On the positive side, it did give me more time for thorough prep for the antifouling. Ended up taking the rudder off as I found small cracks allowing water entry. Also a small leak in the keel.

So, my expected cost effective do-it-myself antifouling not only cost a lot more with extra slip fees but Windchaser is out on her mooring less her rudder while I keep working on it. It will be more fees to get the rudder back on.

I guess if I want to look on the bright side, I actually enjoyed doing the antifouling, apart from standing in the rain doing wet sanding. And, the developing problems with the rudder and leak in the keel could have proven disasterous if they had not been noticed and attended to.

Next time, would I do the antifoul myself? Yup!

[Swift]

Hi Bruce

Troppo makes some good points. Incidentally I was recently discussing antifouling with the guy who's 36 ft boat is moored behind Swift. He was saying that there's already growth on the bottom of his boat which was only antifouled 6 months ago by Gladesville Bridge Marina. He didn't specify what type of antifoul he wanted so I suppose he got wahtever was the cheapest. This contrasts with my boat which I last antifouled in March 2010. I'm not knocking the Marina, (my brother who's boat is also moored in Tarban Creek uses them every year and is happy with their work), I'm simply using this to illustrate that 3 boats moored in the same place can have totally different results depending upon choice of materials and application. Marina's assume that boats will be hauled out every year and work to this. Unless you ask for and pay for more you only get a basic job that may last a few months more than a year but not much more.

When you do it yourself you have time for a thorough wet sanding which ensures that if you boat was a bit rough when you bought it, it will get a bit smoother each time instead of adding to the continual antifoul build up which eventually leads to the necesity of a costly total stripping down to the gellcoat. Also, if you use a quality product like Micron Extra you can apply it in accordance with International Paints recommendation which is 2 full coat plus a third coat on high wear areas (waterline, leading and trailing edges) The standard "2 coats" done by most marinas is usually only one full coat with the second coat only on high wear areas.

If you roll out the Micron Extra well 4 litres will be enough including the third partial coat. The trick is to stir well and stir some more and if it's not flowing properly use only a small amount of antifoul thinners. BTW I note that Whitworths now sell the more expensive Micron 66. This used to only be available for professional spray application. The data sheet states that it can be applied by brush or roller but the number of coats to be applied is up to 5. Could this be because the amount of solids in Micron 66 is only 40% compared to 60% for Micron Extra? Or because it's thinner and will roll out further? I don't know but as Micron 66 is supposed to be the best in the International range I would try it out when I pull Swift out next month except unfortunately I already bought some Micron Extra when it was on Special a few months back.

If you do decide to do it yourself you're not about to cause yourself a lot of grief because antifouling is one of the easiest jobs you can do on a boat. Just remember to reverse the usual painting process, instead of starting at the top and working down, start at the bottom of the keel and work up and out, this avoids crawling around under toxic paint. Also keep an extension pole for the roller handy so you can roll the keel and some of the bottom from a standing position. Additionally it helps to use a different colour each time so you can be sure of total coverage and also see where the paint is wearing off the most which provides a good indication for not so obvious areas that require that important third coat.

As far as painting the topsides what type of paint are you going to use?

cheers
Keith

[Bruce]

Thanks for the replies.

I might jump over the side with a mask when the water starts warming up and see if there's a forest growing there before deciding what to do.

Still deciding what to paint the hull above the waterline with. Two pack or single. Easy or hard...

[Killick69]

My 2 cents worth.......suggest you go for 2 pack (pain the ....) i painted the stripe under the toe rail with single pack a year and bit ago and if i rub my hand on it, there is reside on my hand.

Cheers, John