Cast iron keel antifouling

[goboatingnow]

Historically the yard has anti fouled my boats but since I’ve all the time in the world these days and the labour rates are only going one way I’m thinking of taking over the job

I have an iron keel , fouling here in the Ionian is low , so I get two years ( I usually get a diver to scrub it )

What’s the best way to treat the keel ( see pic ) there’s no significant rust.

Does it need to be abraded back or will I just over seal it. Or apply touch up metal sealer paint on spots without removing the old antifouling

Basically what can I get away with , without stacks of work

[tkeithlu]

Don't put paint over untreated rust. Sand it (not wire brush it), prime wherever you see bare metal, and paint it. You may end up priming the whole thing.

[goboatingnow]

Originally Posted by tkeithlu

Don't put paint over untreated rust. Sand it (not wire brush it), prime wherever you see bare metal, and paint it. You may end up priming the whole thing.

Why not wire brush ?

[tkeithlu]

The problem is that a wire brush leaves a really smooth surface, with minimal adhesion for paint. If you use a brush (I do), then sand the surface lightly before priming.

[Privateer01]

I use POR15 to deal with any rust, then over coat with Interprotect 2000 and anti fouling. Buys me a few years.

[kenbo]

POR15 is just a very expensive moisture-cured urethane paint. Any MCU will serve the same purpose. Corothane by Sherwin-Williams is an excellent MCU at half the price. There are others as well.

[c.K.]

if they let you!
rent a power washer at least 3500 and use a rotating tip about $45+ you'll be amazed how far this will take you

[Privateer01]

Originally Posted by kenbo

POR15 is just a very expensive moisture-cured urethane paint. Any MCU will serve the same purpose. Corothane by Sherwin-Williams is an excellent MCU at half the price. There are others as well.

Fair enough. Just relating my experience.

[kenbo]

Originally Posted by Privateer01

Fair enough. Just relating my experience.

That was a rushed post on my part. I had a fair sized portion of my business in rehabbing cast iron keels and after needle scaling we used 2 coats of MCU. Then faired the keel, primed and then antifoul.

[FULLCIRCLE331]

Looks like the keel on my 331. I grind out the rust then apply interprotect 2000. Every year I have repair some place on the keel. The repairs hold up well but always some new spots that show up in the spring after on the hard for three months. You need at least three coats.

If you put the interprotect 2000 in the freezer you can use the same mix for a week or more.

[goboatingnow]

Thanks. I wimped out and the yard is doing the prep work. I just have to then apply the anti fouling