Priming and Fairing a Lead Keel

mhdyachtsman · Post by **mhdyachtsman** » Fri Mar 14, 2008 9:19 pm

I am having a problem with paint adhering to my lead keel, so after pressure washing the keel, I used an abrasive grinding disc and removed most of the remaining paint.

Is there a special primer which I can apply to the lead before fairing, which will allow the bottom paint to stick?

Do I need to go the Interlux 2000 route to solve this problem?

Has anyone tried the Marine Bondo to fair a keel?

Thanks

rshowarth · Post by **rshowarth** » Fri Mar 14, 2008 9:58 pm

On our Mariner Cast Iron swing keels, we used thickened epoxy.

I have heard of some using POR 15 to paint as a primer.

I do not know if it might work for you.

Post by **Tim** » Sat Mar 15, 2008 7:08 am

One thing to keep in mind is that lead oxidizes very quickly. So you need to re-grind it to bright white metal immediately before applying whatever your chosen product is--fairing compound, primer, or paint. A nice coarse grinding also helps provide "tooth" for better adhesion of whatever comes next.

"Marine" bondo is cheap polyester just like the auto stuff. Don't use it or any polyester for filling. You'll have much better bonding and overall success using epoxy fillers, particularly on a lead keel where bonding strength is the key.

If you're going to fair, then apply the fairing compound before any paints or primers; other wise, the fairing compound adheres only to the paint and therefore relies entirely upon the paint's bond with the substrate.

CharlieJ · Post by **CharlieJ** » Sat Mar 15, 2008 8:48 am

To get a good bond to lead, the Gougeon's recommend sanding with a rough grit THROUGH the wet epoxy. Then you have zero chance of oxidation on the lead ( or other metal you are bonding).

Once that coat cures to a green stage, you can apply the epoxy filler.

Works well on cast iron surfaces also.

On our own keel (cast iron) we then coated with Coal Tar epoxy and painted with anti fouling.

mhdyachtsman · Post by **mhdyachtsman** » Sat Mar 15, 2008 5:47 pm

Thanks for the advice. I think I am going to fair it with Interlux Watertite, and then go over it all with the Interlux 2000 system. I just need the temperatures to warm up, we had snow today.

I forgot to mention, the boat is a Sabre 28 I am redoing.