Keel joint

[fred1diver]

Hey everyone, getting anxious about all the work to be done this spring, I’m wondering how bad this keel joint is, there is a little rust line at the joint, should I worry about it? How should I work on it? Just grind/sand apply some filler and paint or is it a bigger job?

 

[PaulK]

Looks fairly standard. Grind/rake it out and refill/fair/paint.

 

[DArcy]

Grind, fair, paint. And check your keel bolt torque. Looks normal for a "mature" boat.

 

[Barnacle Bill]

Looks like a cocktail when it comes with various coatings the boat has received in past years. The keel joint itself doesn't look suspect. The cast iron is attached to fiberglass and so there might be minute movement, but doesn't look like it is coming apart. Any grooves can be ground out, cleaned, painted with an epoxy primer, filled with an epoxy fairing compound, sanded smooth and repainted with more primer. The rest of the keel should be cleaned up to get rid of the rust and then coated with something like Pettit's rust lok primer (which is an epoxy and attaches well to rust) and then coated with something like INterprotect 2000/2000e multiple times, which is an epoxy barrier coat. The whole hull should be sanded frosty clean for a good tooth and then antifouling of your choice applied.

 

[Bob J.]

I seem to remember there's a product I've seen others recommend for fairing keel joints called G Flex? It's supposed to be forgiving. If I got this wrong please forgive me.

 

[dlochner]

I seem to remember there's a product I've seen others recommend for fairing keel joints called G Flex? It's supposed to be forgiving. If I got this wrong please forgive me.

G Flex is an epoxy made by West System. It is designed to be a bit flexible where as most epoxies and resins are hard and brittle.

The keel/hull joint is always problematic because of the differential rates of expansion between lead or iron and fiberglass. Add to that there is the flexing that occurs while sailing. There are no 100% solid cures for the issue. No matter the repair, the crack reappears; sometimes quickly, sometimes after a long while. If there was an ideal solution, the solution would have good adhesion and good elasticity.

G Flex would be a better choice than straight up thickened epoxy and much better than 3M 5200. Both 5200 and epoxy are not flexible enough for a permanent cure.

Specialty Epoxies | WEST SYSTEM

Try WEST SYSTEM® Specialty Epoxies, cure-compatible with each other, and also with the 105 System. Learn more about our products here.

www.westsystem.com

 

[Crazy Dave Condon]

5200 was the product the manufacturers used for years and still do as a sealant when marrying the keel to the hull and considered to be permanent. In fact I have seen pulling fiberglass off a hull where used. Just like anything it wears out. Never worked with G Flex but retired years ago as a former dealer. In fact 5200 is called satan’s glue.