Fairing keel-hull joint

[yalcin]

Greetings from Panama,

On our Ericson 38, we made some miles and ended up hauling out in Panama, in the middle of a jungle. This is a French operated DIY yard. The long list of our projects include installing a new shaft seal, eliminating rudder play and a new bottom paint.

Unfortunately, when we started to sand around the keel hull joint, what we thought as a simple paint crack turned out a bit of a bigger problem. We do not think the joint is compromised but we are confused about how they constructed this joint from the outside.

We can see the bedding compound (where the paint flaked off) and it seems in tact. There's some loose fiberglass we were able to peel off, and there's some foamy filler on the trailing edge of the keel. My theory is that they laid a layer of fiberglass cloth over the hull and the keel to get a smooth painting surface after fairing. Does this make sense?

We still have sanding to do in order to get rid of all the loose pieces. Has anyone encountered a similar problem? What's the best way to fair this surface for painting? Should we try to glass it like it was or will a simple epoxy putty do it?

 

[Christian Williams]

For what it's worth, my boat doesn't have any fiberglass overlap between hull and keel.

In my opinion you can fill and fair the hull joint with anything you like, using the usual materials.

Old caulk typically needs to be dug out, and if the bottom hasn't been treated to paint removal and new barrier coat, the buildup can be a quarter inch or more after all these years. It does look like a heavy buildup.

I'm not an expert.

 

[driftless]

Our boat came with the same cracking at the leading edge of the hull to keel join when we bought it. Our surveyor recommended glassing over it. It's entirely possible someone did so on your boat.

I did some reading and decided to epoxy with thickened gflex instead. That joint is going to flex some no matter what, so I'm hoping the elasticity of the gflex will hold up better over the long term than more rigid glass.

I didn't see any foam filler as you describe, but there were many colors and layers of gelcoat, filler, fairing, and paint, in the area as we ground it down to fill.




After a season of about 600 nm of sailing there is some minor cracking in the new bottom paint over the area at the very leading edge of the keel. I'll probably just lightly sand and paint over it this spring.

I'm even less of an expert than Christian.

 

[bigd14]

Looks familiar. I hogged out as much of the sealant in the seam as possible then added new sealant (Sikaflex 291 if memory serves). Once the sealant cured I used thickened GFlex epoxy and a thin layer of fiberglass cloth to fair it over. The cloth is likely unnecessary as it will not do anything to hold that joint together. I also tightened the keel bolts. Haven’t hauled out for over a year but the last haul out the joint was perfect (3 years after repair). I think the keel bolt tension is the most important factor in the stability of the joint. There can be other issues that are documented on this site including the mold release wax not being cleaned off during construction that can cause that joint to have issues also.
Good luck with the repairs.

 

[Dave G.]

I had the "smile" and used West G-Flex to repair. You need to clean out the entire joint and sand/grind a V shape for the epoxy fill. Try to fair it well when you put it in as it's not fun to sand. Then apply fairing compound, sand, barrier coat then bottom paint. I wouldn't glass the joint as I think the flexing of the the two surfaces would crack it. Just my 2 cents, I'm no expert either.....

 

[Pete the Cat]

I think you can fill it with whatever you like. It does not look structural. I put graphite tape on the joint on my Tartan 37 and it did not crack---until i hit a rock at 7 knots. But that is another story. If you have not done it before you might try to torque the keel bolts while you are out. I think I was in the marina in Panama---is it on the Atlantic side down from Colon? I left my boat there for a month or so.

 

[yalcin]

Thanks for all the replies. We're convinced this is nothing structural and anything that will hold the paint will do.

When we read about what sticks to the metal part, we learnt about a method to deal with the surface oxidation of lead. For the metal part, we need to clean it to shiny metal and apply epoxy resin right away. But apparently this is not enough and they recommend "sanding it in". From what I understand we wait a little and sand the metal through the wet epoxy layer. I honestly don't know how this will work in practice but we'll give it a shot in the places where metal is exposed.

It's hard for me to judge since I'm inexperienced but the buildup does not look too thick. At least the paint buildup does not look thick.

I think I was in the marina in Panama---is it on the Atlantic side down from Colon?

There is a marina/boatyard in Colon (Shelter Bay marina) but they are not as DIY friendly and they are relatively expensive. A lot of people love it there but it wasn't what we were looking for. We're at a place called Panamarina, a super basic boatyard with a trailer to pull the boats out. Cheap and we can do all the work. It's French operated so although they don't even rent vacuum sanders, they have a restaurant with very good food.

 

[Pete the Cat]

Thanks for all the replies. We're convinced this is nothing structural and anything that will hold the paint will do.

When we read about what sticks to the metal part, we learnt about a method to deal with the surface oxidation of lead. For the metal part, we need to clean it to shiny metal and apply epoxy resin right away. But apparently this is not enough and they recommend "sanding it in". From what I understand we wait a little and sand the metal through the wet epoxy layer. I honestly don't know how this will work in practice but we'll give it a shot in the places where metal is exposed.

It's hard for me to judge since I'm inexperienced but the buildup does not look too thick. At least the paint buildup does not look thick.

There is a marina/boatyard in Colon (Shelter Bay marina) but they are not as DIY friendly and they are relatively expensive. A lot of people love it there but it wasn't what we were looking for. We're at a place called Panamarina, a super basic boatyard with a trailer to pull the boats out. Cheap and we can do all the work. It's French operated so although they don't even rent vacuum sanders, they have a restaurant with very good food.

I was at Panamarina as well. I had one of the scariest experiences of my life approaching it. As you know there are a lot of reefs you need to thread to get to the place. While I was slowly motoring through there, the fresh water pump started spraying steam and water all over and I had to shut down and start sailing. I was single handing and somehow managed to sail between the reefs and change out the pump (I had a spare and a lot of experience with my engine) in about 15 of the most stressful minutes of my sailing life. When I was there, 10 years ago they had big plans but no travel lift or restaurant. It was essentially a mooring field with a dinghy dock--but the French couple running it had big plans. A stop for folks on the way to San Blas and an option to Shelter Bay. San Blas was a high point of my cruising life.

 

[Prairie Schooner]

We have a similar situation, though in a less exotic locale. The bottom paint is really rough, but we're going to tackle it next fall. We'll do just good enough prep and painting to get us through the year. What would you use to seal the joint that would be relatively easy to take off in six months?

 

[mjsouleman]

Jeff/Donna,

To seal the joint try Jamestown Distributors TotalBoat TotalFair Epoxy Fairing Compound, it provides moisture resistance and can be used above or below the waterline. It dries quickly and then paint over it.

https://www.jamestowndistributors.com/product/product-detail/97775

Mark "Souleman" Soule

 

[Kenneth K]

I've had similar cracks & flaking away of barrier coating along my keel joint (E323). A shipwright I was using in 2016 told me, "if it was my boat I would glass it over, but I don't have to charge myself labor."

At his recommendation, I've just painted over it at every haul out. I've never had leaks at the keel joint or a widening of the cracks.

I did snug up the keel bolts (to 200 ft-lb) on my previous haul out, and the paint over the joint seems to have held up better (I just hauled out again last week) than it did on previous haulouts.

Last week:

 

[yalcin]

We faired the area and painted over it. We did not torque the keel bolts. The crack reappeared very quickly after the launch.

Next haul out, one of the work items will be to torque the nuts to the specs. Maybe there's a way to do it in water but I feel like putting the boat on the keel is necessary.