Painting my bottom...Any tips for a first timer)

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thesaintlyone

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Hello
I have finally removed the old layers of Anti-foul and sanded smooth the bottom of my Westerly Jouster 21 and now need to apply bottom paint.
Im looking at Hempel Cruiser but open to suggestions (price is a big factor here)

Some have suggested primer as well any oppinions, suggestions tips etc for a first timer
 
In theory you're supposed to use a primer over unknown old paint just in case it turns out to be incompatible with the new. On a small budget boat I probably wouldn't bother.

Other than that it's not rocket science, just get a cheap disposable roller tray set from B&Q and slap it on. If you have paint to use up at the end but not enough for a full coat, the place to put it is on the leading edges of keels, the bow, the rudder, etc as these tend to wear away first.

Pete
 
apply underwater primer as a keying coat first.
best check out various manufacturers websites yourself for info
to apply a/f i use a 7" roller ( a fine emulsion roller / smooth for gloss ) on a pole. a foam roller may disintegrate due to solvents in the a/f
 
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From reading and practical experience I would say that, having done all that sanding down, a primer is ESSENTIAL !! And not too expensive.
I have used a variety of the cheaper anti fouling paints Flag and others, with good results. I think Hemple is probably fine.
Keep some of your primer to cover up any 'failed' patches next season.
Good luck
 
To do Hempel Anti-Foul Cruiser and underwater primer works out at £60 so not bad on price.

What is the timescale between the two i.e. can I apply the Primer then the Anti-foul a few days later or does it need to be same day etc

Regards
 
5 coats of epoxy primer then 2-4 coats of antifoul depending on your plans. Perhaps Copper coat on a 21 would be the best investment going. I hate antifouling, awful for health, EU (with UK) looking at banning it for public application for good reason because for anyone who has used the stuff it gets everywhere although I find I get covered in more antifoul on "boat launch" day when it is in the slings than I do when applying it on the whole boat.

Either way listen to whatever prv suggests, he is approaching 30,000 posts!
 
Oh just slap it on. Contrary to advice elsewhere on here, I use small size budget foam rollers from Screwfix. Yes they do tend to die on you but just dump the dead one and replace. I find the small rollers easier to work with, especially on a small boat. Junk the tray and rollers, retain the handle: but then I always manage to loose the handle before next year and wind up buying a new one anyhow......
 
Starting afresh on a clean hull I'd use one coat of primer, then two thin coats of AF, then every year another single thin coat with extra around waterline, keel and rudder leading edges. Personally I'd rather use a little strong AF than a lot of cheap stuff as sooner or later you have to get it off again, which is a vile job.

If the hull is newish or tested as dryish (moisture meter) the epoxy is a good idea: I wouldn't bother on an old or 'moisture meter wet' hull.
 
What you put on your bottom really depends on where you are. If you are in the north of Scotland where fouling is low, go for an average to cheap antifoul. If you're in the central south coast you'll need a powerful (read as: expensive) antifoul. Remember that a cheap antifoul that doesn't work very well is a waste of your money.

Apply the thickness that is specified on the tin and keep the rest of the tin for touch ups.

Coppercoat doesn't work for me in the central south. It probably wouldn't work for you either.

Soft antifoul can usually be put on top of hard, but the other way around is asking for trouble and paint falling off.

If your bottom is properly bare and smooth gel coat, I'd suggest you get it epoxied first, otherwise just get antifouling and go sailing ?
 
What no one has said here is find out what people have success with where you intend to moor. And it can be those boats within 50-100 metres ( at West Mersea, it's different depending which creek you're in, and can't be compared with say Brightlingsea, or Bradwell), whichever it is, apply the appropriate primer (epoxy will I suspect be over budget) and two coats... The PBO best overall performer was Seajet Shogun if you can't get the info
 
Jamesuk said:
5 coats of epoxy primer then 2-4 coats of antifoul depending on your plans.
Click to expand...

I'll be putting a barrier coat and anti-fouling on my yacht very shortly. The expert I approached said to apply 5 coats to get the thickness required of around 20 mil. But it is not a big deal as you only have to leave one hour (depending on the temp) between coats. (The pot life of the product is around 10 hours)

But he says it is important not to delay putting on the first coat of anti-foul. I should have asked him why but I presume it is to get a chemical bond to the barrier coat other wise the anti-foul would not stick to a cured epoxy barrier coat.
 
Just to clarify.
The recommendations about epoxy are because if you have spent a lot of time on getting your bottom totally prepared then now would be a good time to consider epoxy.
However it needs to be totally clean and ( ideally abrade to form a key) The epoxy is to make your hull 100% watertight and reduce osmosis risks.
probably you don't want to go down that road so you just need a coat of primer and ( as suggested) 2 coats of thinish antifoul. Antifoul will not 'stick' to gel coat you do need primer!
 
Can't see the point of epoxy unless you know the hull is dry already - old Westerly -> probably not.

Definitely use primer to stop anti-foul flaking off when applied directly to the gel coat. One coat will do, but a second will do no harm.

+1 on local advice on anti-foul. However most effective ingredients seem to be banned or limited these days, so the expensive anti-fouls don't seem to be worth the extra.

This year I'm trialling Seatech from www.svb24.com. (Curious that UK chandlers consider it too dangerous to fly anti-foul from the UK to Ireland but a German chandler was willing to fly it over the UK for about five pounds :) )
 
+1 for applying some 2 pack epoxy eg International. You have spent time cleaning and sanding the bottom, now is the time to protect your investment with the recommended 5 coats of epoxy before antifouling. It's quick and straightforward to put on if the weather is not too cold. It goes on quite thin.
 
On my old wooden, I use 2 coats of primer on any bare wood, then a "thick slap it on" coat followed by next day with a thinner "touch it up" coat. Worked so far.

I agree with those who say to ask what others in our locale use. I use Hemple tiger and on the Hamble there was no growth but a fair bit of slime. In OV I have yet to see the results but from above it looks cleaner after longer in the water.
 
Jamesuk said:
5 coats of epoxy primer then 2-4 coats of antifoul depending on your plans. Perhaps Copper coat on a 21 would be the best investment going. I hate antifouling, awful for health, EU (with UK) looking at banning it for public application for good reason because for anyone who has used the stuff it gets everywhere although I find I get covered in more antifoul on "boat launch" day when it is in the slings than I do when applying it on the whole boat.

Either way listen to whatever prv suggests, he is approaching 30,000 posts!
Click to expand...

That's WAY over the top. Fouling varies greatly with your location - in mine it's hardly necessary at all. Ask around to see what your neighbours do and do likewise.
BTW on a small boat, you may find that 4" rollers are more manoeuvrable although you cover the area a lot quicker with a larger one. Foam rollers don't disintegrate immediately so can be used until they go 'squishy' if you've nothing better.
 
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