How to PROPERLY treat a keel?

Count Monaco

Seaman Apprentice
Joined
Jun 8, 2013
Messages
43
A couple months ago, my centerboard/swing keel rusted inside the sailboat so I had to pry it out with a crowbar. I went to a boat supply store and the doc said that because the keel a 25-year old piece of cast iron, it's not uncommon for them to swell up or rust and get stuck. Well, he prescribed me a few products and some simple instructions:
  • Sander to sand the keel.
  • Sodium dioxide? Apply it and the rust will turn into iron.
  • Marine primer spray paint.

Well, that lasted for a couple months and now it's doing the same thing again. In the back of my head, I knew it wouldn't hold up. I thought it was strange that he said no other paint was needed and that the primer would suffice.
 

64osby

Admiral
Joined
Jul 28, 2009
Messages
6,799
Primer is not a finish coat or a good seal coat. Properly applied paint will proper sealing coat.

It swelled - due to rust?

I would think it would have to be ground down to remove the rust. Then prime and paint.

Rust never sleeps. Once it forms it is very hard to contain.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
Oh yes POR 15 IS the stuff. Not cheap, but folks swear by it. I would agree with WOG to make sure you sand/grind down all the rust first to good clean bright metal then apply the POR15 Rust treatment and carry on...
 

tpenfield

Moderator
Staff member
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Jul 18, 2011
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17,620
I re-furbished the iron keel on my Catalina 22 a while back . . .

Ground it all down to clean metal . . .

Applied cold galvanizing compound . . .

Epoxy fairing to smooth it

Added 50 lbs of lead to the end of it . . .

Encased it all in fiberglass with epoxy resin . . .

here is a link to my web pages on the project . . . http://home.comcast.net/~tpenfield/C22/keel2b.html

and a pic or 2 from the project . . .

zinc1.JPG


epoxy.JPG


fiberglass4.JPG


I kept the boat for a couple of years after refurbing the keel. then I sold it to get a power boat. So, I know it lasted at least 2 years, but not sure if it has lasted 10+ years . . .

Iron Keels are a several year maintenance item regardless.
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,924
TPE, I'd say that was a really nice restoration. I've never owned a "Windy" but I'm sure those keels can/are problematic. Anyhoooo, You seem to have handled it well.;)
 

tpenfield

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Jul 18, 2011
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Thanks WoG . . . the spec weight on the keel was 550 lbs. I added another 50 lbs to the end of the keel by casting some lead in the shape of the profile. Along with the fiberglass, it was probably 600-620 lbs when I got done.

Only problem at that point is that it was almost too heavy for me to get back into (underneath) the boat :eek:

I'd like to get me another sailboat someday . . . just need to find the time.
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,924
Yeah, I read your BLOG on the total restore!!! Sounds like you had some issues but...as always you plodded your way through em and came out smiling on the other side!!!! I was on a 10' sailboat when I was in college once, but I was so inebriated I fell off of it and had to swim to shore!!!! Glad it was a small, shallow lake cuz I was able to walk/stumble the last hundred yards. If Not I probably would have DROWNED!!!!:facepalm: My friends had to drive around to the other side of the small lake to retrieve the boat a few hours later.;)
 

pauloman

Petty Officer 3rd Class
Joined
Sep 8, 2005
Messages
89
best is an aluminum filled Moisture Cured Urethane (MCU). these include Rust Bullet, POR 15 or Aluthane - google any of them for price and availibility - prices vary a lot
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
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Jul 23, 2011
Messages
47,297
POR 15 used to be good. I have used it for 20 some years. however in the past 3 years I, along with a few friends have had issues with it. we can no longer recommend it.

however encapsulating it like Ted shows in the pictures would be a great way to keep the rust at bay for a while.
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,620
Using epoxy is the key to get better water resistance. I sold the boat to a guy in Scituate, MA in 2004 . . . So I have lost track of it since then to see how things held up.

Anybody see a Catalina 22 named "Essentials" ???
 
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