All_at_Sea
Well-Known Member
I am just about to start on my keels. What metal primer do people use for underwater use?
Primer sealer for metal bilge keels
- Thread starter All_at_Sea
- Start date
Caer Urfa
Well-Known Member
I asked the same question some years ago to International Paints and they said Primocon min 3 coats then 2 x antifoul , however I used Jotun Vinyguard silvergrey 88 just the same if not better and a whole lot cheaper SML Marine Paints - Jotun Vinyguard
Concerto
Well-Known Member
If you have any rust, you should treat this with a rust converter like Fertan. Then as Caer Urfa says.
Tranona
Well-Known Member
Another vote for Jotun - however you have to buy 5l, so although per litre it is much cheaper you may find Primocon lower cost as you can get it in smaller quantities!
Spirit (of Glenans)
Well-Known Member
Buy the 5 litres, you will be repeating the job over and over.
boatiebert
N/A
Dulux Trade Metalshield Zinc Phosphate primer. Everything rusts through & has to be redone, so may as well compromise a little on price
Bilgediver
Well-Known Member
That could be the answer. I have always used a coat of Primocon as a tie coat between successive coats of antifoul on my Westerly. The keels were last fully treated around 1990 when grit blasted to clean metal and Primconned immediately . There has been minimal rusting since which is always dealt with by taking back to polished iron and repeating as before using antifoul/Primocon.
Tranona
Well-Known Member
Why pay £120 for 5l of Metalshield compared with £35 for Vinyguard, particularly if you say it does not work anyway?
Spirit (of Glenans)
Well-Known Member
Apologies for the thread drift, but in another thread very recently the balance of opinion was that apart from rust-treated areas of the keel, you don't need a coat of Primocon under every coat of A/F, just scrape any flaky bits and patch with Primonon, then lightly wet-sand the rest and apply new A/F directly on top of old. It's what I've been doing over twenty years of boat ownership and volunteer work on club boats.
barnicaljohn77
New Member
I have metal keels on my Alouette,,which have always been a problem. I used 2coats of polyester resin originally, after having them blasted clean . Then antifoul on top.It lasted for years. But now I'm considering having them galvanised. Is there any downside to this?
Thanks, B.
Thanks, B.
Tranona
Well-Known Member
Galvanising is fine - shot blast first. However you will of course have to remove them first! You did well to get polyester resin to stay stuck to steel. If you don't want to remove them and can blast in situ then 4 or 5 coats of epoxy is perhaps the most effective way of keeping them protected.
CAPTAIN FANTASTIC
Well-Known Member
I agree with treating it with Jotun. I used Jotun for the keels (can not remember the exact product name) with very good results.
Dellquay13
Well-Known Member
5L of Jotun got me 2 super thick coats on my bilge keels.
it was back in April in the cold, so in warm weather it might have spread further, but it would have just meant more coats for the same thickness.
it left an easy to paint surface for the a/f afterwards.
it was back in April in the cold, so in warm weather it might have spread further, but it would have just meant more coats for the same thickness.
it left an easy to paint surface for the a/f afterwards.
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barnicaljohn77
New Member
Thanks everyone. ( the keels are bolted on ,so can be easily removed).. An afterthought...with either epoxy or galvanising; would sacrificial anodes be any good?
