Anti Fouling Dilema

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danny_boy

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Hi all :)

I'm not a frequent user of the forum but Ive had some good advice in the past so I'm hoping someone can help me out with this new dilema (everytime I look at my boat I seem to find a new one lol).

Ive got onto re painting the the anti fouling, the old stuff is very dull and very patchy. There are places where the old has worn off completely, some of the rubber from the guide wheels on the trailer has worn onto it, there's even places where it's gone right back to the fibre glass. All in all it's a bit of a crud state.

Can anyone tell me the best process to get it back into shape ? Do I need to fill the dents, re prime and then apply new anti fouling (as my friend suggested) or is there another route I need to take ? I'm not sure if primer will take to the old anti fouling ?

I'll wait untill I get some advice before even looking at it. Anything I've done off my own back has been a mini disaster so I'm trying to do it the right way first this time :p

Thanks to anyone who reads and special thanks in advance to anyone who replies !

Dan
 
If you really want to do it the right way first time, then I believe you should remove completely the old antifoul/primer and start from the beginning. Or even better (you mention somewhere fibreglass; is there any epoxy paint between the fibreglass and the primer?) apply 5-6 layers of epoxy paint on the fibreglass, then primer and then antifoul.
 
The 'proper' job is to remove the old AF. Its also a 'horrid' job. IF the surviving original is adhering properly, then it would be possible to fair it up, then prime it to insulate it from the new coat. This will get round any problems with incompatibility. However, if there is any question about the old coat beginning to flake off, then it has to be removed, otherwise it will continue to flake taking your expensive new coat with it!

However, if the original is 'soft' antifoul - the eroding type, then you can not put a 'hard' type over it, even with a priming coat to insulate it. It will not stick. If you want to put hard AF on, then you will have to remove all the old stuff.
 
slap it on

you mention trailer wheels

so does the boat live on a trailer - is it a trailer sailer?

is it on an all tide mooring


if its a trailer sailoer don't bother antifouling at all

the slug has been without for two years now - in commission all year round

I just beach it and scrub it occasionally

maybe twice a year

occasionally I have a scrub at the water lime - takes a moment and that is where most of the weed will be

if you are not racing then just buy the colour you like, clean the hull with a good scrubbibng brush, mask up the top line and slap two coast on

it is the way it supposed to work

if, on the other hand you want a lot of work.....and enjoy lieing on your back in the grubby mess in a boatyard more than you do sailing

then do what the people above suggest, remove the old stuff - wearing a mask, carefully bag and remove the dust and particles to a safe disposal site etc etc etc

apply five layers of epoxy - making sure the temperatures are good for curing it




then slap the antifoul on as above

but then I am a minimalist and speed is not important

when I was racing sonatas and eboats then of course I loved all that work as I thought it made me a better sailor

Dylan
 
Hi OldHarry

Argh sounds like a mini nightmare !

The old stuff isn't flaking at all, it's pretty well on there, even a palet knife doesn't touch it without some real force but I do think it's the soft eroding type of antifouling, it has a weird feel to it, doesn't feel hard if that makes sence ?

Well, it looks like I'll be stripping it all back to the core and doing as you've instructed. Atleast then I'll know that I won't have any compatability issues and it will be a thorough job. I can't even start to think about it going on and flaking off ...

So I strip it all off back to the fibreglass (doesn't look like there's epoxy between it and the primer) Epoxy paint it 5/6 coats, Prime and then Anti Foul. Sounds doable in a few days, not too bad ?

Thanks a million for your reply buddy, really appreciated !
 
Hey Dylan

I took all the old wheels off the trailer, didn't like the horrible scuff marks and more to the point the preasure that they put on the bottom of the boat while in transit.
Ive put runner boards on now coated with a thick outdoor carpet, much better and supports the boat lovely !

Anyway, she hardly sees the water really compared to most other boats. I take her out once a week, wash her down every time. She's never in the water for more than 8hours a time really.

So I could just fill any scratches, dents, rub them down and paint ? Will paint take to the antifouling thats already on there ?

Thanks for your reply too buddy ! Could have saved me an awful lot of time !
 
Antifouling paint

Yes well it sounds like you don't need A/F paint especially if you don't leave it in the water for long periods.
Here in Perth with loads of sun and warm water a boat will go about 2 weeks without a.f before it has grown significantly.
I imagine in UK you could go for months.
If you were going to leave it in the water yes you need to apply a/f. Now this job of removing the build up of a/f is really a horrible job. It is likely to be the cause of you missing a lot of sailing. It is quite a reasonable approach to put off the removal and just add more. Doing the very best job on boats is not always the best way to go. Pragmatists unite and go sailing. olewill
 
William_H said:
I imagine in UK you could go for months.
Click to expand...
We left our tender in the water during June and in 3-4 weeks it had a good growth of slimey weed - quickly cleaned off (apparently!).

To the OP - if you're dry sailing your boat - ie only in the water when you're using it and out for the majority of the time then you don't need A/F. Just a hose down between sails is all you need.
Pretty much the same as any dinghy you see out sailing ...
 
William_H said:
I imagine in UK you could go for months.
Click to expand...

We wish! In the peak growing season, and when there are lots of nutrients being brought down the rivers to where our mooring is, then we can have a very healthy growth in a couple of weeks.

This summer, we din't use the boat for a few weeks and when I scrubbed off we gained two knots of boat speed for the same engine revs.
 
danny_boy said:
Hey Dylan

I took all the old wheels off the trailer, didn't like the horrible scuff marks and more to the point the preasure that they put on the bottom of the boat while in transit.
Ive put runner boards on now coated with a thick outdoor carpet, much better and supports the boat lovely !

Anyway, she hardly sees the water really compared to most other boats. I take her out once a week, wash her down every time. She's never in the water for more than 8hours a time really.

So I could just fill any scratches, dents, rub them down and paint ? Will paint take to the antifouling thats already on there ?

Thanks for your reply too buddy ! Could have saved me an awful lot of time !
Click to expand...

Obviously 2 quite different approaches you could take.

1 Remove all old antifoul. Started doing that on an old Boston Whaler I had. Soon gave up and moved onto 2. And that was only 15'. But being on a trailer access is difficult.

2 As it's not kept afloat anti foul is not important but as it's already painted and option 1 is a real balls ache just find cheapest antifoul you can buy and slap it on to improve the looks.


Depends on how meticulous you want to be.
 
danny_boy said:
Anyway, she hardly sees the water really compared to most other boats. I take her out once a week, wash her down every time. She's never in the water for more than 8hours a time really.
Click to expand...
You don't need any A/F.
 
Wow thanks for the great responce guys !

Ok I have come to the conclusion that it is already painted with soft antifouling, I run my finger over it and it leaves a paint dust on it.

It hasn't seen new anti fouling for a long time, Ive had it 4 years and before that it was probably a year or two since it saw new paint.

I do want to paint over it as its looking tatty, it had a hole forming where the old wheels were digging into the hull in transit (why i changed them to boards) which I mended with fibreglass and resin. There's a few holes etc so I would like it to look a bit better than it does.

I'm just worried that the old anti fouling isn't going to accept the new paint (whatever I decide to put on) layer and will blow or flake after a while.

Would rubbing it all down with wet and dry give me any better purchase with the new paint ?
 
If you want to paint the hull, as compaired to re-antifouling, you must remove all the old antifouling first or the paint won't stick for long. The general consensus is that you should not dry sand antifouling, as the dust created is toxic. Sanding with wet n dry, used wet, will remove the antifouling, but will take a long time. You can buy a hand scraper, with a tungsten blade, which will give much faster removal of antifouling (but be careful you don't cause deep scratches), and then wet sand to finish before priming and painting. Alternatively, if the bottom looks reasonable after removing all the old antifouling, you could just make good any damage with fibreglass / gelcoat, sand with very fine wet n dry to give a good finish, and leave it at that.

I agree with the advice that antifouling is not neede for a boat which lives on a trailer.
 
I agree with two

longjohnsilver said:
Obviously 2 quite different approaches you could take.

1 Remove all old antifoul. Started doing that on an old Boston Whaler I had. Soon gave up and moved onto 2. And that was only 15'. But being on a trailer access is difficult.

2 As it's not kept afloat anti foul is not important but as it's already painted and option 1 is a real balls ache just find cheapest antifoul you can buy and slap it on to improve the looks.


Depends on how meticulous you want to be.
Click to expand...

buy some cheap black antifoul - it will stick to anything - it will abrade but it will look fine for a couple of seasons

it is a waste of good poison (irony alert)

- but the formulation will be designed to stick

so if you want the easiest and quickest option then do that

dylan
 
danny_boy said:
I'm just worried that the old anti fouling isn't going to accept the new paint (whatever I decide to put on) layer and will blow or flake after a while.

/QUOTE]

Stop worrying.

If you've got it to the point of not flaking, coat it with International Primocon, or some other reputable primer, then give it a couple of coats of anti foul, and go sailing.

Alternatively, you could live with the way it looks, do nothing, and go sailing :)

Primer is designed to resolve your problem so there is little chance of it not working.
Click to expand...
 
danny_boy said:
Hi all :)

I'm not a frequent user of the forum but Ive had some good advice in the past so I'm hoping someone can help me out with this new dilema (everytime I look at my boat I seem to find a new one lol).

Ive got onto re painting the the anti fouling, the old stuff is very dull and very patchy. There are places where the old has worn off completely, some of the rubber from the guide wheels on the trailer has worn onto it, there's even places where it's gone right back to the fibre glass. All in all it's a bit of a crud state.

Can anyone tell me the best process to get it back into shape ? Do I need to fill the dents, re prime and then apply new anti fouling (as my friend suggested) or is there another route I need to take ? I'm not sure if primer will take to the old anti fouling ?

I'll wait untill I get some advice before even looking at it. Anything I've done off my own back has been a mini disaster so I'm trying to do it the right way first this time :p

Thanks to anyone who reads and special thanks in advance to anyone who replies !

Dan
Click to expand...

Whatever you do it seems the rubber guide wheel will score the new paint - yes?
Are you worried about the prospect that some rougness in the AF will slow the boat perhaps as much as 0.01 knot? If not, use medium grit emery paper (must be wetted at all times) to fair the edges of the "dimples" in teh AF, the lay on a couple of coats of AF primer - it sticks to just about anything - finalise with AF and you;re back in business.

If you really want to get back to glassfibre, then prime and finish, you are in for a miserable and arm bashing experience - one that many of us have undertaken, but just once!

I recently reduced my AF using one of the slosh on, scrape off compounds you can buy: a big tub costs £100+ They work, but there's a lot more effort in it than admitted by the suppliers.

PWG
 
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