Keel Flaking off large patches on both sides

[Bob Pullen HC-33 1981]

Recently we've noticed our keel has been scaling off in large patches on either side of the keel. It's happening approx. halfway down the keel (about 1.5' to 2' below the hull/keel seam), about even midships, anywhere from 18" to 10" size patches, and close to even on either side of the keel. The paint and some of the gray looking metal interior has flaked off.
We plan on hauling out anyway next year, so we are trying to research possible repairs and prevention of re-occurrence.
Wondering if we can use the West Epoxy w/ the sealant additive, as we have some of it onboard, and most other products will be difficult to get in this part of mexico?
Seanorita is a 1981 Hunter 33, not the shoal draft version - not sure what the keel is made of.
Any suggestions and enlightening in this area will be certainly appreciated.
Many thanks
Bob Pullen
S/V Seanorita
Yucatan

 

[Joe23455]

Your keel is more then likley LEAD. The paint is pulling off probably due to
layer on layer. Some of the lead can scale off. Not an uncommon happining.
The epoxy system does work nice for fairing out the surface of the keel.
Then follow up with primer and bottom paint. It is important to grind off some area around the scaled off paint and get down to the lead in order to get a good bond of epoxy to lead. Enjoy your boat ! May be some other ideas out there. But this is what I have found on my sailboat.

joe
s/v trinity

 

[Navicula]

not sure what your flaking off.......is it paint or lead or steal that your flaking off..........pictures would be good even with an underwater camera.

however...I did have a flaking issue on my lead wing keel.....not sure if it was due from the cold winters or not ...........but I was getting some flaking of lead on my keel......it was more like a buldge, one on each side....when the boat was on the hard I took a grinder to the buldge and flaking...and kleened it off and filled with the west epoxy and sanded smooth.......

they used a sand cast for my type of keel and some of the sand (impurities) got inside, which over time created some rust which expanded and it buldged and flaked....

I have been told that this is not so uncommon.......I hope this helps ........I could be way off for your issue

 

[Bob Pullen HC-33 1981]

Thanks for the suggestions.
Glad to know the lead scaling is common...will probably remove all the paint layers on the lead part of the keel, followed by sealing & patching with the epoxy/sealant additive, fairing, priming and painting.
Thanks again
Bob

 

[jibes138]

Lead will oxidize very quickly when exposed to the atmosphere. I have done this on my boat and it has worked well for over 10 years. Grind off all material down to bare lead . Wear a wonderful respirator, you don't want to inhale lead dust, highly TOXIC. As fast as you can coat the surface with WEST epoxy or equivalent. Before coating the other side sand it again to get to good bare lead then coat other side of keel with epoxy. Let epoxy cure. Coat with a second coat of epoxy on both sides. Now put two coats of barrier coating, interlux or equivalent. Supposedly this is a good base for paint adhesion. Now before the last coat of barrier coat is fully cured put first coat of paint so the paint will chemically bond a bit with the barrier coat, this is called hot coating, I think MaineSail has a few posts about it somewhere in the archives. Any way add a few more coats of paint and your trouble will hopefully be gone. The epoxy is intended to keep oxygen away from the lead so it dosn't form lead oxide that paint will not stick to at all.

 

[Bob Pullen HC-33 1981]

thanks Dave! sounds like a detailed comprehensive plan that should cure this for a long while! I appreciate your help.
Not sure I can get the interlux barrier coat down here, but I do have an ample supply of west epoxy, hardner, & the barrier coat additives (#422 & #423)
I'm hoping that will give me the sealing properties
All the best
Bob

 

[FourPoints]

I had a small piece of the plastic coating chip off my lead keel a couple years ago leaving the bare lead exposed. I sanded down around the area and faired the plastic out a couple inches to where it was still adhering well to the lead, and then applied MarineTex over the whole area, and sanded smooth once cured. Two full seasons later and it was still holding strong when I hauled out a couple weeks ago.

 

[dont08901]

We recently purchased a Legend 37. When the boat was hauled out for the survey I noticed flaking on the keel. Is this the same thing? Don T.

 

[jibes138]

Bob Pullen, I used a belt sander to grind off all the paint down to bare lead, worked great and fast. I also used an electric drill with sanding disk so I could get in areas that weren't smooth enough for the belt sander. The sanding disk is flexible. Very little hand sanding involved at all.
The barrier coat is not to keep water out, the epoxy does that, it is supposedly just for paint adhesion. I think the instructions I had were from the WEST folks so check their website for detailed instructions.

 

[bffatcat]

keel repairs

last october when I hauled my boat I noticed large areas of the protective coating on my cast iron keel flaking off The guys on the board advised scraping off the entire coating which I did. followed by a coat of pettit one part rust protection and 2 coats of WEst epoxy system

I did all of the above so far so good. will put 2 coats of ablative bottom paint this spring
seems to me you are doing the same job with the omission of the rust protection
should be ok