First time antifouling...

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RJJ

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Hello, advice would be welcome please on antifoul prep. Will need to move fast as soon as permitted. I have never done this before. Yacht has a good base of last year's antifoul which I propose to key in and paint over; but I have just fitted trudesign skin fittings which presumably want priming. Also the volvo saildrive leg needs priming and antifoul.

Questions please:

1. Is PPE required for painting phase? Or just the wet sanding phase?

2. Any recommendations on primer? Only a small quantity needed

3. Do I use the same primer for the saildrive?

4. Any recommendations on antifoul for the saildrive? Again only small quantity needed.

Any other pearls of wisdom will be welcome
 
Primocon as a primer is fine for most things I believe. Wet abrade old Antifoul. Never dry abrade. Wear gloves and glasses. Wash skin well. I once got a clogged pore after antifouling and wasn’t nice.

I always do two thin coats rather than one thick. Extra layer at the water line. Small rollers better. Foam rollers tends to disintegrate so use thin pile rollers.

We often get two years out of one application even if they lead you to believe it needs doing every year. Depends on where your moored of course.
 
Saildrive antifoul shouldn't have copper in it so the usual big tins are a nono. I use some stuff in a spraycan; forgotten name as its on boat ( could be Trilux).
I think its pointless trying to get a smooth finish like you would on topsides or joinery at home. The antifoul is just there to deter weed and barnacles so I just scratch enough to give a key.
I've used Primocon to tosh on if any patches appear down to the gelcoat.
Check anodes as well but don't paint them
 
I was nervous first time but 25 times later I have a method! PPE - yes, industrial rubber gloves, overalls, eye protection and a breathing mask although I don't think the mask is really essential. Use one of those foam blocks with coarse abrasive and sand the whole hull wet. Scrape off any flaking paint and barnacles with a paint scraper. Wash down, I use a cheap broom to rub off any residue. Have a cuppa and let it dry. Now go back and spot prime any bare patches. Next day mask up the waterline and paint! Two coats if you like. Here's my guide with pictures: How-to Guide: Applying Antifouling Paint - Boat Angling
 
I found that the area most in need of extra a/f is the area just below the bow where it smacks down in choppy water. A/f seems to disappear quickly there. I am not convined about the need at water line. ol'will
 
salar said:
I was nervous first time but 25 times later I have a method! PPE - yes, industrial rubber gloves, overalls, eye protection and a breathing mask although I don't think the mask is really essential. Use one of those foam blocks with coarse abrasive and sand the whole hull wet. Scrape off any flaking paint and barnacles with a paint scraper. Wash down, I use a cheap broom to rub off any residue. Have a cuppa and let it dry. Now go back and spot prime any bare patches. Next day mask up the waterline and paint! Two coats if you like. Here's my guide with pictures: How-to Guide: Applying Antifouling Paint - Boat Angling
Click to expand...
Thanks, do folks recommend full PPE for the painting phase as well as the sanding phase?

V helpful so far, thank you
 
Sand down the saildrive with 180 grit. If you go to the aluminium you should prime with an epoxy primer. That being said I sometimes have not bothered & it has been Ok. . Then apply a couple of coats of trilux 33 from international. A small tin will last a 3-4 of years. Remember to clean the wet paint out of the drain screw slot before it dries otherwise you will be chipping it out & spoil the screw at a later date

For the log & echo sounder I suggest you use Marlin ECO transducer paint. It is expensive, but lasts years, provided you add a bit of water to it & stir the paint 2-3 times a year to prevent it going hard. When applying, overcoat the surrounding area by 5mm because even exposed mastic from the bedding compound will attract weed which will drag back in the water flow & clog the impeller. You may also use it on the true design stop cocks.. Water it down a bit to apply.

When preparing for antifoulpaint do not just slap it on. Smooth out the ridges from the sub surface so you get a smooth surface. Poor application does slow the boat somewhat regardless of what some might say.
Before I changed to Coppercoat, I worked on removing a 1/3 section of the old paint each year so that it prevented excessive build up. removing the whole yacht would be hard work so moving along the hull each year is easier.
 
Old clothes with full sleeves. Tuck cuffs into long gloves .
Safety glasses and a dust mask.

Main thing is to not breathe in the dust or get too much on skin so wet sand if necessary.

Never seen need for primer if the boat has already had AF ... but a new surface - yes.

Roller it on ... brush where need to cut in ... having taped / masked anodes / through hulls ...

I knew a guy who used to get a small brush and AF his paddle wheel and inside of speed log !! Not a good idea really ...

Just have a good shower / bath after ....
 
[QUOTE="Refueler, post: 7103820, member: 32157"
I knew a guy who used to get a small brush and AF his paddle wheel and inside of speed log !! Not a good idea really ...
[/QUOTE]
Add me to that guy, because I do not have to remove mine to clean it throughout the season. See my post #7
Raymarine recomend correct antifoul paint always be applied to their units
 
Daydream believer said:
[QUOTE="Refueler, post: 7103820, member: 32157"
I knew a guy who used to get a small brush and AF his paddle wheel and inside of speed log !! Not a good idea really ...
Click to expand...
Add me to that guy, because I do not have to remove mine to clean it throughout the season. See my post #7
Raymarine recomend correct antifoul paint always be applied to their units
[/QUOTE]

I know some do recc'd .... but this guy was slapping on standard Micron ....

Only time I've had to withdraw mine was when it clogged with mud after ploughing through the mud at low tide ... otherwise in **** knows how many years - never had any fouling or problems with mine not A/f'd
 
Pressure wash put antifoul straight on I put two coats last a full year no problem, my first time I scraped all old off took ages that was 28 years ago since then I have done it many times dried out against a wall over low tide does'nt seem to have come to any harm, I use eroding paint so not much left after a year.
Mike
 
Check the differing types/brands max time until launch. Most common is about three months max before going in the water. In the current situation you won’t be launching or sailing anytime soon; 3-4 month, if ever this year. Maybe a waste of time and money.
 
Many years ago different antifouling could react with each other so barrier coats used to be necessary.
Nowadays there does not seem to be a problem.
We have a scrubbing grid. Every boat gets power washed then the new coat applied, maybe two.
Immersion/drying times are certainly not adhered to but it still works.
I'm sure a lot of these binding/priming coats are not needed.
For boats with no af then straight on with af is not a great idea
 
If the AF is in good condition, it should be enough just to clean it after pressure washing with a coarse 'scotch pad', which I do on a pole, wet of course. There are many variations in application. I use a 9" roller on a light pole and get two coats on a 34' boat in one day. Attention to rolling technique is needed, to get a smooth surface and for economy. I leave the speed log unpainted but just give it a light coat of silicon grease. If you are using cheap masking tape, don't leave it on for more than a day, a lesson that many of us have learned the hard way.

The saildrive is probably best painted with Trilux, which some people also use for the prop. Trilux is available as a spray or tin.
 
RJJ said:
Hello, advice would be welcome please on antifoul prep. Will need to move fast as soon as permitted. I have never done this before. Yacht has a good base of last year's antifoul which I propose to key in and paint over; but I have just fitted trudesign skin fittings which presumably want priming. Also the volvo saildrive leg needs priming and antifoul.

Questions please:

1. Is PPE required for painting phase? Or just the wet sanding phase?

2. Any recommendations on primer? Only a small quantity needed

3. Do I use the same primer for the saildrive?

4. Any recommendations on antifoul for the saildrive? Again only small quantity needed.

Any other pearls of wisdom will be welcome
Click to expand...

I did it once ... in 2012 when I first got the "big boat" .... it's only 11,5 metres long but it took me a week and I ended up knackered every evening and looked like papa smurf - despite protective gear..

Never again.

It was the nastiest, most unpleasant job I've ever done on the boat and ever since I've paid someone else with all the right equipment to do it for me.

Have a go, and see how you get on (y) .

Some tips, don't put any general purpose copper based paint on your saildrive leg - get the right paint for the job (primer and antifoul), don't paint over the anodes, and there is special anti-foul for the prop.

Have fun - I don't envy you one little bit.

IMG_7400.JPG
 
RJJ said:
Thanks, what is the "drain screw slot"? I am sure it's a good warning but I don't know what you're on about ☺
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Normally there would be a drain point in the bottom of the saildrive where one can drain off the gearbox oil. There certainly is on the Volvo one that I have. If the boat is new to you, it might be worth changing the oil & checking for water in the oil. if signs of water then the shaft seals may need changing.
The screw needs a big screwdriver & needs to be fairly tight. If it is full of paint yu will not be able to turn it. When replacing it needs a correct new washer. Not the old one. I made the mistake a few years ago & ended up having my boat lifted when on holiday to change the oil & washer due to water in the gearbox. I had been told by French engineers it needed new shaft seals but fortunately it was just the washer & I avoided loss of holiday & a large bill
Some will say it is unnecessary, but I change the oil every year as I can clock 200 hours some years
 
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Daydream believer said:
Normally there would be a drain point in the bottom of the saildrive where one can drain off the gearbox oil. There certainly is on the Volvo one that I have. If the boat is new to you, it might be worth changing the oil & checking for water in the oil. if signs of water then the shaft seals may need changing.
The screw needs a big screwdriver & needs to be fairly tight. When replacing it needs a correct new washer. Not the old one. I made the mistake a few years ago & ended up having my boat lifted when on holiday to change the oil & washer. I had been told by French engineers it needed new shaft seals but fortunately it was just the washer & I avoided loss of holiday & a large bill
Some will say it is unnecessary, but I change the oil every year as I can clock 200 hours some years
Click to expand...
Ah yes thanks. No visible problem with oil however it will be changed and seals replaced as part of a saildrive and gasket service. Now I know what screw you refer to. Much appreciated.
 
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