Iron bilge keels and epoxy

[petersto]

I have recently bought a centaur with iron keels which are badly rusted and pitted. What is the best method of cleaning and protecting for the future. Also I need to stick some batten to the inside of the cabin aft bulkhead to fix marine ply does it have to be marine epoxy or will motor factor epoxy do.

 

[pvb]

Keels...

I did a similar job some years ago on a Westerly Pentland bilge-keeler. Thorough scraping off of loose stuff, then thorough wire-brushing (I used rotary brush in an electric drill), remember to wear a breathing mask. Then several coats of Primocon - follow the instructions on the tin to the letter. Finish with antifouling. This treatment lasted quite well, kept the keels looking reasonable for several years.

 

[tr7v8]

Most rust proof paint I know of is POR15, POR is paint over rust. American and I'd suspect epoxy based, sticks like well you know, don't get it on you or your clothes as it needs an angle grinder to get off.
I believe UK supplier is Frosts and they and the US manufacturer have a web site.
Do a google and if you can't track it down send me a message and I'll look it out.

Jim
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[PaulAG]

I also have a Centaur with the same problem. A previous post suggested the underseal used on cars was good.
As for the cabin deckhead lining, we used 'No More Nails' for the battens but as this took quite a while to 'go off', we also screwed the battens to the deckhead(make sure then screws do not go through the deck head!) Be careful about the levels in the deckhead as there are some steps that need levelling out with either glued wood blocks or epoxy filler. The original glue (Evostik?) is a devil to clean off effectively. In cold weather a wire brush is OK, but when warm is impossible!
We also noted that as the mast compression post is off-centre, positioning centrally-split ply panels (suitably covered) were best off-set also, so that a cutout in one panel only was needed for the post.
Good luck!!

PaulAG

 

[Tantalus]

Re: Keels...

Best treatment I've heard of was ...

Remove old coatings down to bare metal.
Coat with epoxy
While epoxy still wet, wire brush the epoxy into the metal using a non-ferrous wire brush.
Since iron begins to rust almost immediately when exposed to air this supposedly suspends the minute rust particles in the epoxy thereby isolating it from the iron of the keel and sealing it in suspension.

 

[petersto]

Paul
Thanks for that however it is the aft bulkhead ply that I am changing apparently water gets in somehow and rots the ply. Its placed on a dollope of epoxy(I think) just spread over the ply. The mast support was mentioned in the survey its suprising how many owners have not noticed.

 

[howardclark]

Had a Berwick for several years - At first I used the traditional method of ignoring it, but strangely it didn't go away, just got worse.
Next clean off & epoxy - most epoxies simply don't adhere as well to metals as to other materials though I understand that specialist products such as VC Tar from International will do well.
So after a couple of years I got a local to sandblast it and apply first coat of Primacon immediately (i.e. within minutes). A few more coats of Primacon then fill, fair and antifoul or whatever. This was a much better job. A drawback was that where the keels were stood on wooden supports we couldn't sand blast - the rust will then spread out again over the surface, but I found a light use of the angle grinder and more Primacon next year kept it at bay.
Later I was advised that I should have had the boat held up in slings for the sandblasting to get the last bits of rust off - probably would have reduced the annual maintenance a lot.

 

[castaway]

Last year year I had "Fairweather's" bottom slurrey blasted to get 30years of old A/F off. The ballast keel was also exposed and had a reasonable amount of surface rust.
I used Fertan, an organic rust neutraliser to coat the keel with , and have had almost no rust appearing through this ( and a layer or 2 of Primacon ) this year.

Nick

<A target="_blank" HREF=http://www.yachtsite.co.uk/fairweather>http://www.yachtsite.co.uk/fairweather</A>

 

[tr7v8]

Just found web-site for POR15:-

http://www.por15.com

Jim
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[petersto]

Thanks everybody for taking the time to reply all good information. I find the site and the info. invaluable.

 

[RichardPerou]

Best advice I had was:-

1. Put an anode on each keel.

2. Don't worry about it.