keelbolt pocket

[Figment]

I've had this lump of lead on the leading edge of my keel that's been bugging me. About the size of a large scoop of ice cream, I know it had minimal affect on performance, but man it just BUGGED me to look at it. Today, while fairing a few other underthings, I decided to take a few slices at it, expecting to strike the head of a keelbolt before long and just fair it in from there with putty.

but nooooooo.


I shave the whole thing down and discover that there's a hollow pocket behind it. The hole you see is big enough for my index finger, but the pocket behind is roughly the size of the shiny area of lead. the pocket is deep enough that my finger can just about reach the keelbolt within.

Interesting bit of trivia: The keelbolt has a T-shaped doweled head like I've never seen before.

So what the F do I do now?
I'm inclined to slap a piece of biax over the hole and deal with it next year, but I'm open to ideas.

[jhenson]

I wonder if you could stuff lead shot suspended in thickened (very thick) epoxy up there. You could wedge a sheet of plywood under the hole till it kicks.

Joe

[Jason K]

Take up smuggling?

[bcooke]

Weird, very weird...

I think I would attack it by filling in the hole before glassing over it. Since you don't need the extra weight I don't think I would add the lead shot. I think I would just fill with thickened epoxy but then the problem is how to get that much in there without starting a fire. If you could squirt a bit in at a time I would go that route. Maybe cut a bigger access hole and epoxy a rock or something just to fill the hole (now THAT would be crude) or maybe this is where adding lead shot or something that takes up space without adding to the heat buildup would be good. Then go ahead and add a few layers of biax.

If you fill now then you will not have to revist the hole later. I think having an air pocket a couple of feet under the waterline would be an invitation to water intrusion or ... something ... I just don't know what. It can't be good though. On the other hand the cavity has probably been there for over 40 years so what is the problem really. In that case just cover it up!

There. I covered my bases. Fill it, or just cover it, or just do nothing. Any more questions?

Any thoughts how this could have come about? Could the lump of material you removed have "flowed" out from the cavity or do you think it was some kind of cover-up/repair?

-Britton

[Rachel]

There. I covered my bases. Fill it, or just cover it, or just do nothing. Any more questions?
-Britton

Gosh, Britton - I just hope you'll still be here with sage advice when I get my boat project going. How will I manage otherwise? ;-)

[kendall]

possibly seal the bottom with with a temporary patch, then drill into it at an angle from the top and use your selected filler, lead shot and epoxy as suggested earlier, or a cheaper resin as you don't need the strength.

or just two tubes wrapped with tape to seal them to the hole, one to force epoxy in and one to let air out.

It's interesting, I've seen tons of bubbles in lead, but never as you described.

Ken.

[Figment]

oh, I don't think its an accidental bubble. It's a deliberate pocket for the keelbolt.

My, um.... suspicion is that the lump of lead was a cap, of sorts, that was soldered onto the keel to enclose the pocket. I'm considering soldering a sheet of leadcoated copper over the hole to creat a similar cap.

The keelbolt itself is in remarkably good condition. I would think that a bolt sitting in seawater (the pocket was full of water) for 40 years would show more corrosion. Part of me wonders if the whole pocket thing isn't the result of bolt replacment.

[bcooke]

Interesting Mike.

Are any of the other keel bolts similarly constructed or does the early model Triton have just the one to begin with?

I really haven't got a clue but soldering sounds like more work and it might be prone to leaking after awhile. I still like the fill idea. You can always grind it back off assuming you can find the spot again.

Gosh, Britton - I just hope you'll still be here with sage advice when I get my boat project going. How will I manage otherwise? ;-)

Oh don't you worry. I have plenty more where that came from and with my boat in its current condition I won't be going anywhere for awhile :-)

-Britton

[Figment]

soldering sounds like more work and it might be prone to leaking

Except that I'm the son of a furnace serviceman! I learned to solder before I learned to hammer a nail.

[Tim]

The keelbolt itself is in remarkably good condition. I would think that a bolt sitting in seawater (the pocket was full of water) for 40 years would show more corrosion. Part of me wonders if the whole pocket thing isn't the result of bolt replacment.

I don't know, but I do know that the original keel bolts are Everdur, which would (and does) stand up almost indefinitely in this sort of environment.

Pearson may have cut plenty of corners, but at least they used good material where it counted most.

[bcooke]

Pearson may have cut plenty of corners, but at least they used good material where it counted most

Funnily enough I was thinking about that yesterday when I was removing some mahogony fiddles with bronze screws that hold the whole interior in place. I am not meeting those high standards in the rebuild. I also notice that all of the plywood they used is much better than the stuff I can get at Home Despot and looks as good as new under the bad paint job (so good in fact that I am cutting it up and re-using it in other places). Even where it really didn't count they sometimes went the extra mile. I suppose though it was cheap and readily available back in the good-old-days...

Everdur? What's that?

-Britton

[Tim]

Everdur was a brand name for silicone bronze fasteners.