Keel Blister

PalmettoSailor · #1 (**permalink**) 04-12-2007

Ok, I looked searched the forums and couldn't find where this question has come up before.

My boat has a blister on the top of the winged keel. The keel is lead and it appears that water has penetrated whatever the keel was faired with and opened up a big blister. It's perhaps 2-3 inches around.

I'm guessing I need to chip off the fairing material, grind/sand the area smooth and apply a new coating before the antifouling goes on. The material seems pretty tough and will no doubt require some effort to clean up. Then there is the issue of getting something that will stick to the lead.

Is this the correct course of action or should I just smooth it up and paint it? If I need to fair the area what product should I use?

Gary M · #2 (**permalink**) 04-12-2007

A picture in these cases is always good. If this was a bulb that was added after original construction chances are that it was bolted or lag screwed onto the existing keel and a layer of epoxy was applied to act as an adhesive and sealer.
Chances are they used either WEST epoxy of Marine Tex. In a either case just grind it smooth and check for further penetration. Clean up and repair with either of the above mentioned epoxies. You can buy either in small quantities. From the apperance of yours you should be able to tell which one it was. If you are using WEST and you need very much you probably should add some of their filler like 404.

Gary

sailingdog · #3 (**permalink**) 04-12-2007

You should find out how the water go in to make the blister in the first place if you can and seal it off... Either MarineTex or West will be good, but you definitely should thicken the West epoxy with one of their fillers, not the Colloidial sillica though...

I also agree that in cases like this a good photo is always helpful.

CapnHand · #4 (**permalink**) 04-12-2007

Top of the wing, or top of the keel?

I saw a C&C 30 with a blister near the top of the keel. The broker said that water from the bilge can seep down from the keel bolts and if it freezes in there, it can cause a bulge. In this case the lead just been ground smooth in a 6 to 8" dia area. There were no apparent cracks.

The remedy that the broker suggested was to always put antifreeze in the bilge for winter lay-up.

I solved the problem by not buying that boat

PalmettoSailor · #5 (**permalink**) 04-12-2007

Quote:

Originally Posted by CapnHand

Top of the wing, or top of the keel?

I saw a C&C 30 with a blister near the top of the keel. The broker said that water from the bilge can seep down from the keel bolts and if it freezes in there, it can cause a bulge. In this case the lead just been ground smooth in a 6 to 8" dia area. There were no apparent cracks.

The remedy that the broker suggested was to always put antifreeze in the bilge for winter lay-up.

Ya' I should have thought to take the camera last time I was down at the boat, but didn't and its about a 2.5 hour drive away.

It is a "Hydrokeel" winged keel on an Oday 322. As far as I know, its cast with the wing, but I suppose it could be two parts fastened together somehow, though there is no evidence of a seam between the vertical and horizontal areas of the keel.

The blister is on the upper surface of the horizontal wing about mid way between the outer edge and the vertical part of the keel. I also forgot to mention that the blister is cracked open. Whatever water the flaw lets in only touches the lead keel, so I'm not worried about any strucural problems or water getting into the hull material or the boat. Its at least 4 linear feet to the nearest fiberglass.

SailorMitch · #6 (**permalink**) 04-12-2007

There's an O'Day 32 of some sort on the hard at my marina with a wing and I'll check it out this weekend to be sure, but chances are the wing has an epoxy coating on it that became brittle in that area and let water in. As you can tell from my signature line, I'm on my second Pearson with a wing, and the coating that Pearson put on their wings back when is very subject to "blisters." Chip away the loose material, clean it up a bit, and then apply some thickened epoxy over it. Let the epoxy cure, sand smooth, apply bottom paint and go sailing. Unless I find something strange on the O-Day at my marina, it's no big deal.

PalmettoSailor · #7 (**permalink**) 04-12-2007

Quote:

Originally Posted by SailorMitch

There's an O'Day 32 of some sort on the hard at my marina with a wing and I'll check it out this weekend to be sure, but chances are the wing has an epoxy coating on it that became brittle in that area and let water in. As you can tell from my signature line, I'm on my second Pearson with a wing, and the coating that Pearson put on their wings back when is very subject to "blisters." Chip away the loose material, clean it up a bit, and then apply some thickened epoxy over it. Let the epoxy cure, sand smooth, apply bottom paint and go sailing. Unless I find something strange on the O-Day at my marina, it's no big deal.

Thanks, I'm pretty sure it's not a big deal, I had just heard that lead is difficult to get stuff to stick to. Sound like thickened epoxy is what I will need to use before the paint.

Now if the weather would just cooperate. 2" of snow on the boat last weekend, now they are forecasting rain and temps too low to complete the sole refinishing project. Seems like I'm going to be the "last one in".

sailingdog · #8 (**permalink**) 04-12-2007

Sand the lead lightly and clean with a degreaser... then put the thickened epoxy on.

2redtrek · #9 (**permalink**) 04-14-2007

I too have a 322 with the same problem nothing that some scuffing and epoxy to fix it up.

hellosailor · #10 (**permalink**) 04-14-2007

"The broker said that water from the bilge can seep down from the keel bolts and if it freezes in there, it can cause a bulge."
If there was sufficient water in the keel bolts to blow out the keel, the keel bolts need to be replaced.

Midlife-
Lead isn't a problem if you work with a fresh surface and roughen it up so whatever you are putting on it can get a grip. If you want to fo the repair the traditional way...you build a clay dam around the void, fill it with molten lead after preheating it, and it will bond in just fine. Basically you are soldering, that's all. (That's how dents in cars were fixed before fiberglass come out.)
After it cools, you file it down and finish overcoating it with epoxy, bottom paint, whatever suits you and matches the rest.

Lead is easy to obtain, you can get used tire weights often free from a local tire store, melt 'em down in a tin can over a propane torch, scoop off the dross (iron FLOATS on molten lead) and then just add some plumber's soldering flux and pour it into the void. (If you do this, do it outdoors and stay upwind of the solder, lead isn't healthy for you.)

Molten lead is fascinating, it looks very much like icy cool water, which of course is exactly what it isn't.