Keel Bolts on older (60's and 70's) sailboats, show me yours!

[Morgali]

Hi All,

I am debating whether or not I should pull my keel studs out and replace them, or just clean up the surface rust on the tops of the studs/nuts. I dont think the rust is excessive, but I am not 100% sure on how deep it penetrates. From an initial inspection, it appears to be just surface rust. The survey noted it as surface rust as well.


So, if you have an older boat like mine, please, show me pictures of yours! especially if you replaced yours, show me the old and new!

[Aethelwulffe]

Depends on the keel material, and the makeup.


Some old boats have a sort of a flange at the root of the keel, and bolts are used to secure the keel to the canoe-hull shape.
Others have cast-in-place allthread. For those, especially in cast iron fin keels, I just drill down into them, machine in sideways through the keel to make a bolt access and landing, then sister in new bolts with LOTS of bedding compound.
Many keels already have filled center-bolt setups like that, and you can chip out the filler to access the nuts.
In NO case have I ever seen that the keel fasteners are "studs" that can be extracted by unscrewing them from threaded holes and replaced in-situ. For wood hulls, you sometimes have drifts used in the keelson, but I doubt that is your case.





-And if your keel-to-hull seam is not wiggling...don't mess with it

[Morgali]

Originally Posted by Aethelwulffe

Depends on the keel material, and the makeup.


Some old boats have a sort of a flange at the root of the keel, and bolts are used to secure the keel to the canoe-hull shape.
Others have cast-in-place allthread. For those, especially in cast iron fin keels, I just drill down into them, machine in sideways through the keel to make a bolt access and landing, then sister in new bolts with LOTS of bedding compound.
Many keels already have filled center-bolt setups like that, and you can chip out the filler to access the nuts.
In NO case have I ever seen that the keel fasteners are "studs" that can be extracted by unscrewing them from threaded holes and replaced in-situ. For wood hulls, you sometimes have drifts used in the keelson, but I doubt that is your case.





-And if your keel-to-hull seam is not wiggling...don't mess with it

It is not wiggling!

My boat has a cast iron keel, and it's going to need some repair on the bottom of it as it has some corrosion at the bottom aft portion of the keel. I am not talking a little bit, either. Probably about 1 inches of keel corroded away at the very anterior of it. My plan is to grind and shape it, protect it, and paint it.

But, that's an aside. My boat isn't worth a helluva lot, but I'd like to be sure that the rust on the studs and bolts from the keel is not dangerous in the "loose your keel while sailing and kill your loved ones" way.

[JimsCAL]

Originally Posted by Aethelwulffe

In NO case have I ever seen that the keel fasteners are "studs" that can be extracted by unscrewing them from threaded holes and replaced in-situ.

Actually many cast iron fin keels are attached that way. Like Benes.

[CarlF]

A first step would be to clean, grease and torque the bolts. If any break or spin during torquing you have your answer.

It is not unusual to find that the front bolt is already broken from a grounding.

It's really best (and often necessary) to drop the keel if replacing bolts. It's much easier than trying to replace bolts in the confines of the cabin. It also lets you completely recaulk the keel joint.

If you don't have torque values for your boat this is probably pretty close

https://j109.org/docs/keel-bolt-torque-table.pdf

[Aethelwulffe]

Perhaps I am wrong in any blanket statement, and I agree that this installation method has been used. Three issues/possibilities stand out though:

1. Tap on the sides of those keels. You may find that there are perforations that allow access to the nuts, and unscrewing the "studs" was also an act of unscrewing them from the immobilized nuts.
2. In the case of true tapped hole and stud installation into cast iron, I ask: So you have successfully extracted these studs and replaced them?
3. Where you see tapped holes most often, you find that they are not STUDS, but bolts. These bolts can be pulled and replaced on the hard, and I have even done some replacements in the water (shallow slip at low tide).
Lead keels have been cast with bronze liners cast into place that accept a bolt. This allows you to sufficiently torque the keel to the hull. Having a nut access port cast into the keel is a lot less expensive and risky method of fabrication, and gives very good options for torquing it into place.



Most often when drilling down into old cast iron keels, the drill bit brings up black dust more than shiny stuff. Expanders and sweating bronze filler has been my best answer there. Wasn't very confident in the fix, but nothing bad actually happened.


Upshot: If this guy does not have a motion issue, he could replace the nuts (with a 300ft-lb torque wrench on the hard), but should not goof with the threads at this point. If those are bolt heads, then they are bolts, and replacing them is totally an option...provided there really really really are not nuts at the bottom end.



Which Cal do you have?

[Aethelwulffe]

Originally Posted by CarlF

A first step would be to clean, grease and torque the bolts. If any break or spin during torquing you have your answer.

It is not unusual to find that the front bolt is already broken from a grounding.

It's really best (and often necessary) to drop the keel if replacing bolts. It's much easier than trying to replace bolts in the confines of the cabin. It also lets you completely recaulk the keel joint.

If you don't have torque values for your boat this is probably pretty close

https://j109.org/docs/keel-bolt-torque-table.pdf

Nice resource...but torque applies to bolt specs as much as anything.
Very good point on the grounding related failures. If you don't have a crack showing at the leading edge, then there ain't anything going on.


@threadtopic don't be shy about just reshaping your keel a bit, fairing over the corrosion pits and all that. I have seen cast iron I thought was totally dead tell a D6 front end loader to go stuff itself when the boat was being broken up for disposal.

[Aethelwulffe]

As CarlF mentioned, it is damn satisfying to drop a keel, clean and rebed everything with fresh pookie and get it all buttoned up again. You know what you have at that point, you know? You go aground inshore to get out of a shipping channel during a sudden whiteout windstorm with chop pounding the keel on the sand, and you just go down below and make coffee thinking "Meh".

[Morgali]

Originally Posted by Aethelwulffe

Which Cal do you have?

I don't have ANY Cal. I have a W.D. Schock Santana 27.

[bikesherpa]

Originally Posted by Aethelwulffe

Depends on the keel material, and the makeup.

Others have cast-in-place allthread. For those, especially in cast iron fin keels, I just drill down into them, machine in sideways through the keel to make a bolt access and landing, then sister in new bolts with LOTS of bedding compound.

Do you have a photo that shows this type of attachment with sideways access ?

[Don C L]

Those Santana 27s are sure sweet boats, worth fixing up imo. I have not yet owned a boat with keel bolts, but I’d favor replacing them. I base that on the case from last year where an old Columbia 28 had its keel fall off due to bolt corrosion. Granted that was not an iron keel. Take it with a grain of salt. I hope some ranger 26 owners will chime in too, they have the same arrangement I believe. You might check Santana 27 website too, they are still pretty active I think. Those boats were ahead of their time imo.

[Morgali]

Originally Posted by bikesherpa

Do you have a photo that shows this type of attachment with sideways access ?

I dont understand the sideways access. Mine has nothing like this.

[Morgali]

Originally Posted by Don C L

You might check Santana 27 website too, they are still pretty active I think. Those boats were ahead of their time imo.

I emailed W.D. Schock and got a response within a couple hours. This is the message I received.

John,

I don't believe at the time your boat was built, Coast Guard numbers were required. Unfortunately I can't remember where they were installed. Look at the inside of the transom, they were probably about 1 inch high. But someone could have painted over them. A rule of thumb is that the sail number and hull number are the same, but if someone bought some new used sails, then that wouldn't apply.
I was working here when your boat was built, but unfortunately I can't remember anything about the keel and we have moved several times so most of our old files have been lost. Have you tried looking for owners on line. Perhaps they could be of help.
I am so sorry I wasn't able to be of help.
Smooth sailing!
Carol

[wingssail]

I wanted to have my keel bolts inspected, as much as could be done, for crevice corrosion. After all, with backing plates and hull thickness there was over 1.25" of bolt which was hidden from view and subject to possible corrosion.

To do that we unbolted the keel (in the travel lift) and lifted the hull off the keel (which was propped up to prevent falling over).

A metal inspection lab came and inspected the exposed bolts, and dye tested them, and reported that all was good.

Then we put the hull back down on the keel, (with bedding) and replaced the nuts.

Any problems farther down in the keel remain un-detected but most keel failures I've seen are at the keel/hull joint, not down inside the keel..

[Don C L]

Originally Posted by Morgali

I emailed W.D. Schock and got a response within a couple hours. This is the message I received.

boy that’s how you know when you have a classic boat! When the builder can’t recall how he did it, you’re on your own!!
How many bolts do you have? I’d say it’s worth it to replace them if there is any doubt.