Lead Keel prep advice

[djousset]

It's my first time doing this level of work and I'd like some advice.

I’m in the final stages of keel/hull fairing and painting (and found this video which appears to be good advice…feel free to confirm or confute….)
https://youtu.be/cH5vMiNBCsU

In a few small areas of the keel I am down to lead and need to know best practices for prep before filling/fairing? Will epoxy adhere without an intermediary agent?

[Dockhead]

All I can say is be careful.

I did my own lead keel a couple of years ago, investing a lot of labor into that, and the paint and everything fell right off of it

Last year I had it sandblasted and done professionally. It seems to be holding now.

I had followed -- I thought -- the required procedures. I carefully degreased the keel and applied an epoxy two-pack primer which was specifically ok for lead.

The very nice guy who did my keel last year told me my mistake was not immediately applying the primer. He said that lead oxidizes quickly and that epoxy doesn't stick to the oxidization. He said you have to paint within a hour (or something) of sandblasting.

Don't know if that's true, but his work seems to be holding up. I found nothign about that in all my careful reading leading up to doing it myself.

I suggest doing thorough research on the correct procedure and materials.

[NSboatman]

There’s nothing quite so valuable as a fellow who has been there, done that, made the mistakes, wears the tee shirt and is willing to share to help others.

Thanks DH

[roverhi]

Best advice I've heard is to use a wire brush to apply the epoxy coating after sanding/blasting to bright medal. The wire brush will insure getting the epoxy or whatever onto unoxidized surface.

[zstine]

Originally Posted by roverhi

Best advice I've heard is to use a wire brush to apply the epoxy coating after sanding/blasting to bright medal. The wire brush will insure getting the epoxy or whatever onto unoxidized surface.

This worked for me. Lead will tarnish when exposed to air, not visibly but compromises bonding. Epoxy will bond fine, but you should sand and apply epoxy as soon as possible, and wire brush it in "neat" (not thickened) before coating with thickened epoxy if need to fill/fair. I've had success with both interlux 2000 epoxy primer (applied immediately after sanding without wire brush, then followed with 4 more hot coats applied when previous coat was 'green') as well as 'laminating' epoxy to fill a ding (applied neat with wire brush, then filled with thickened epoxy)

[jamhass]

Yes, what the others have said about using a wire brush to apply an appropriate primer immediately after taking the lead to bare metal. I prefer a very coarse grit (24 - 40) surface to provide additional grip for the epoxy.

[Fishzine]

As others have said, oxidation is the problem. Here is what I did this winter when i had some exposed lead after checking on keel-hull joint.


Sand whole area down to fresh lead right before applying epoxy primer.
Clean and degrease as normal.
Apply first coat of epoxy primer to exposed lead and wet sand it into the lead with very rough sand paper ( I used 60 grit). This will be messy.... The wet sanding gets the epoxy into fresh lead that is never exposed to the air to oxidize.
I then followed that up with a hammer and chisel to cross hatch the lead under the still wet epoxy.
Brush/roll the epoxy smooth again. continue as normal with all top coats. As far as I know stuck perfectly.

[NSboatman]

There’s nothing quite so valuable as a fellow who has been there, done that, made the mistakes, wears the tee shirt and is willing to share to help others.

Thanks DH

[Quadrille in JB]

My lead keel to fiberglass keel stub continuously weeped when on the hard and slowly leaked into the bilge when in the water. After several tries at grinding and sealing with 5200 I bit the bullet and ground the joint down to the gel coat and bare lead with an angle grinder using 40 grit. I immediately saturated 12” wide strips of 16 oz. bi-axial FG with epoxy resin and applied it to the keel joint, again saturating it and rolling the excess resin out. I repeated this process for a total of 2 layers. The next day, I ground the glass and lead again and Applied fairing compound. After fairing, I ground it once more and immediately applied 5 coats of 2-part barrier coat epoxy, waiting the appropriate time between coats. I then applied 4 coats of SeaHawk Cupracoat bottom paint. I’ve had it on the hard during hurricane season for the past 2 years and it hasn’t weeped a drop of water and the bottom paint looks great.