Sadler 25 single fin keel

[NaBo]

Hello!
I’ve owned my Sadler 25 for a couple of years. Bought it with modifications made by the previous owner, and the one before, and who knows how many

Pulled up ashore a few days ago to do the bottom work. Hoped to just strip the flaking parts of old antifouling, prime and apply new antifouling, but was left with some questions (i.e. how come gelcoat is missing in some substantial area of the underwater hull, but is still there in the other areas?! Or, up to four layers of coatings in some, and just two before fiberglass in others? There is a story there!)

Anyway. The question i have that i would like the answer to: what is the keel made from? Steel? Cast iron? I don’t think it’s lead, judging by a few spots eaten by rust and that it did not feel soft against the angle grinder. Not much info about that online.

I had to move quick this time, because it’s freaking hard to find a boat yard to work in, where i live now (Stavanger, Norway). Without selling my kidneys, that is.

But, in planning for more meticulous maintenance manipulations next summer, i would like as much information as i can possibly gather.

Speaking of, knowing the year of the yacht would be amazing (there is no plaque that i could see).

I have spared you the graphic content of DIY surgery literally done with a hack saw, cutting out the inboard and replacing it with a 100-pound Tohatsu beast casually hanging off the back plate. Have some replaced it with a lighter and longer-stemmed one.

 

[PabloPicasso]

Likely cast iron keel

The most success I've had is;
.remove flacky paint
Treat with rust converter like ferton
Paint with red oxide paint
Antifoul on top

Touch up as needed next year and so on

You'll never prep it perfectly in a boatyard.

 

[Tranona]

Cast iron. Real solution is to blast back to iron and immediately coat with epoxy. Practical alternative is to grind back rust spots, prime and antifoul. Ongoing annual routine.

Gel coat missing is a different issue and again blasting is the long term solution, but patching with an epoxy fairing filler such as International Watertite will protect the laminations.

 

[johnalison]

I had a similar problem, though to a lesser extent, on our Sadler 29. After several year of hard work each year trying to re-prime it I just bought some basic Hammerite and this almost solved it, with only a few small spots to treat each year. This was many years ago and Hammerite is not the same, but you should be able to get a good result with a modern rust treatment, with or without a filler as required.

 

[merjan]

Our early 80’s Impala’s hull look similar when the paint is scraped. At first I was convinced that there was no gelcoat but I read in a few places that pigment-free (=transparent) gel coat (ie just a first coat of polyester resin) is used in some older boats below the WL. I’m not qualified to tell what we are looking at on your boat, but that might be an interesting possibility to get advice on.

 

[William_H]

I would reiterate that anti fouling is an ongoing chore. Do your best in the time available and promise to do better next time. As said cast iron keels always rust and then flake off paint. All you can do is grind or wire brush the area treat with rust converter then epoxy and finally a/f. If you are in a hurry heat the epoxy to cure faster. paint over it when tacky. ol'will