How much attention needs bottom and keel before the boat goes back into the water?

[miraculix]

Hi all,
We are heading towards our third season with our 2008 Beneteau Oceanis 40, so we are still pretty much boat newbies.

The first time I saw the boat on the hard was before we bought it, and the then owner was working on the keel and bottom. I was told the keel and bottom would get a new layer of bottom paint. After that, the boat went back into the water, we bought it, and we spent the second half of the season on the Chesapeake before it got on the hard again for the winter. The bottom paint and the keel looked pretty decent, and we were told some touch-up here and there would be enough, which was done by the marina. The boat got back into the water for our second season and back on the hard in late November 2021.

Now the situation is a little different. The keel has a lot of rusty spots, the bottom paint has flaked off in some areas, and there is even an area where we see the gel coat or even the bare GRP, but I am not sure about that.

I wonder if we have to do some more than just new bottom paint this year before the boat goes back into the water. Definitely work on the keel. Remove the rust—new protective paint and so on. Definitely cover this bare-looking area. The rest of the hull, I am not sure. Unfortunately, I do not know the "paint history" of the hull, like what was done before, what material was used, and so forth.

Anyhow, I uploaded a video to youtube showing the situation.

I appreciate all your comments.

Thanks
Christoph

 

[sail sfbay]

............Now the situation is a little different. The keel has a lot of rusty spots, the bottom paint has flaked off in some areas, and there is even an area where we see the gel coat or even the bare GRP, but I am not sure about that. I wonder if we have to do some more than just new bottom paint this year before the boat goes back into the water. Definitely work on the keel. Remove the rust—new protective paint and so on. Definitely cover this bare-looking area. The rest of the hull, I am not sure. Unfortunately, I do not know the "paint history" of the hull, like what was done before, what material was used..........

Nice video!! You have a good plan..........confirm keel material then sand the keel to remove the rust and paint, fill in holes with epoxy and smooth out, apply 5-7 coats of barrier coating followed by 2 coats of anti-foulant paint. Same procedure for the hull where you have lost the barrier coating. Before you apply anti-foulant paint confirm whether the old paint is hard or ablative by consulting with your diver, boatyard and previous owner (maybe they can supply a record of when and where their last bottom paint was done which is what I do during a used boat purchase) since each requires a different preparation and application procedure. Might find this article helpful: Keels: Minor Maintenance and Repair - Practical Sailor (practical-sailor.com)

 

[Sailfanatic]

Any rust spots - use a wire wheel to grind to bright metal, cover with three-five coats of straight epoxy. Spot cover with paint
Bare spots - sand smooth with 80 grit. Spot cover with paint.
Any areas with well attached paint - a light scuffing with with 80 grit.

Apply one coat of paint to entire bottom.

EDIT: based on your video, your bottom shows a lot of paint buildup, thus the area where paint has chipped off, so a sand-blasting job of the entire bottom is not too far down the road. The rust is so widespread on the keel, I would strip the entire keel to bare metal, cover with epoxy and it should be good indefinitely. I prefer straight epoxy to epoxy barrier coat, because epoxy barrier coat is a softer finish and on the keel I think hard as rock is better. The grey material on the keel appears to be Interprotect 2000 and you can see from the widespread rusting, it hasn't worked so well.

Also, FWIW, I would not use a step ladder to access the boat, but rather a section of an extension ladder. Its a lot easier to fall off a step ladder than an extension ladder, and if you take that fall in a boat yard, you may break your foot and end up hobbling around for a year or two. This is the voice of hard experience.

 

[miraculix]

Thanks for your input!
I think I am going to start by contacting the former owner. You are correct; I should have gotten the "bottom paint history" during the purchase of the boat. Well, that is the problem if one has no experience what are the important questions to ask.
If it doesn't look like that, I have to remove everything and start with a new barrier coat and bottom paint. That would already be a win.

 

[Sailfanatic]

Thanks for your input!
I think I am going to start by contacting the former owner. You are correct; I should have gotten the "bottom paint history" during the purchase of the boat. Well, that is the problem if one has no experience what are the important questions to ask.
If it doesn't look like that, I have to remove everything and start with a new barrier coat and bottom paint. That would already be a win.

FWIW when you decide to strip the bottom, be sure to tell the crew NOT to remove any existing barrier coat, if the barrier coat on the hull is doing the job. If you remove the barrier coat, the blasting process is likely to also open up blister repairs, if any, under the barrier coat and you will need to redo all those repairs prior to re-doing the barrier coat. Better to leave what is working well enough, alone.

 

[TimFromLI]

What they said + use some ospho rust treatment to help keep the rust from coming back.

 

[miraculix]

Hi all,

After some time thinking about the project I have to realize and admit that there is not time enough to do the job myself. We have to travel abroad for some time and that the marina is 3 hours away doesn't help either.
Long story short I talked to the marina and they came up with a plan. Somebody looked at the boat and the figured that the keel should be sand blasted and while we are doing this they suggested to do the whole hull and rebuild the covering from the gound up.
I am not too oposed to that, the boat is now 14 years old and I would asume that that has never been done since new. I tried to contact the former owner to get more information about that but wasn't successful.
I was aware that if I can't do it myself it will be expensive. But now I get to hear that media-blasting the hull will be 169$ per foot. That was significantly more than I thought and a quick Google search only finds lower numbers, I would say in the 40 - 60$ range per foot.
So I am wondering if I missunderstood that... but I am pretty sure I did not.
Anyhow, what is you experience out there in regards to the price of media-blasting a boat hull?