The one way to tell if there's a problem is to remove a couple of bolts.

"Daniel" wrote in message
...
I recently hauled my boat and after few days I noticed allarming
coloured streaks oozing out of the thin crack (very thin and of little
concern by itself) between the keel and the hull.
The colour of the streaks is green-blueish, something that suggests
copper sulfate, and sort of shiny that suggests micro-cristals.

According to the boat makers the keel bolts are AISI 316 SS and the keel
is of lead.
The boat was made in 1978.

Do you have any suggestion? Do I have to drop the keel and check the
bolts? I would rather avoid it, if not really necessary.

Thank you
Daniel

Jim,
Normally the keel bolts will be cast into the leadballast and are not
removable without recasting the keel. They will appear as long studs and
fasten thru the floors with nuts and washers.
Steve

"Jim Conlin" wrote in message
...
The one way to tell if there's a problem is to remove a couple of bolts.

"Daniel" wrote in message
...
I recently hauled my boat and after few days I noticed allarming
coloured streaks oozing out of the thin crack (very thin and of little
concern by itself) between the keel and the hull.
The colour of the streaks is green-blueish, something that suggests
copper sulfate, and sort of shiny that suggests micro-cristals.

According to the boat makers the keel bolts are AISI 316 SS and the keel
is of lead.
The boat was made in 1978.

Do you have any suggestion? Do I have to drop the keel and check the
bolts? I would rather avoid it, if not really necessary.

Thank you
Daniel

I've no idea if it's applicable to ss keel bolts in a lead keel, but it's
certainly possible to detect loss of bolt thickness caused by corrosion for
steel bolts in concrete foundations - as used in chair lifts, power wire
towers etc. Ring a few local non destructive testing companies, it's
reasonably specialised but you might find someone with the right equipment,
experience, and an interest in boats ...
Has to be better than taking off the keel!
David
"Steve Lusardi" wrote in message
...
Jim,
Normally the keel bolts will be cast into the leadballast and are not
removable without recasting the keel. They will appear as long studs and
fasten thru the floors with nuts and washers.
Steve

"Jim Conlin" wrote in message
...
The one way to tell if there's a problem is to remove a couple of bolts.

"Daniel" wrote in message
...
I recently hauled my boat and after few days I noticed allarming
coloured streaks oozing out of the thin crack (very thin and of little
concern by itself) between the keel and the hull.
The colour of the streaks is green-blueish, something that suggests
copper sulfate, and sort of shiny that suggests micro-cristals.

According to the boat makers the keel bolts are AISI 316 SS and the keel
is of lead.
The boat was made in 1978.

Do you have any suggestion? Do I have to drop the keel and check the
bolts? I would rather avoid it, if not really necessary.

Thank you
Daniel

Steve Lusardi wrote:
Jim,
Normally the keel bolts will be cast into the leadballast and are not
removable without recasting the keel. They will appear as long studs and
fasten thru the floors with nuts and washers.

They can be removed. That's what the threads do.

You might have a really tough time getting them to turn... if you put a
slugging wrench down onto the nut, then put on a lock nut over that, you
should be able to get it started.

DSK

"DSK" wrote in message
.. .
Steve Lusardi wrote:
Jim,
Normally the keel bolts will be cast into the leadballast and are not
removable without recasting the keel. They will appear as long studs and
fasten thru the floors with nuts and washers.

They can be removed. That's what the threads do.

I believe he means from the keel itself.

Steve

You might have a really tough time getting them to turn... if you put a
slugging wrench down onto the nut, then put on a lock nut over that, you
should be able to get it started.

DSK

They can be removed. That's what the threads do.


Steven J. Ross wrote:
I believe he means from the keel itself.


So did I


Regards
Doug King

Doug,
On all the lead keels that I have seen, the bolts are held in the keel by
anchors, because the lead is too soft for threads to hold. Very often a
frame is constructed of steel and the the bolt pattern in the frame is used
to drill the mounting holes in the floors for alighnment reasons. This frame
is then cast into the keel. Alternatively, a wooden frame is made to suspend
the bolts head down with large washers and then the keel is cast. In all
cases the bolts cannot be removed without recasting the keel. I suppose one
could use a threaded anchor, but I have not seen that.
Steve

"DSK" wrote in message
. ..
They can be removed. That's what the threads do.


Steven J. Ross wrote:
I believe he means from the keel itself.


So did I


Regards
Doug King

Steve Lusardi wrote:
Doug,
On all the lead keels that I have seen, the bolts are held in the keel by
anchors, because the lead is too soft for threads to hold.

Really? I suppose if you're casting a lead fin around bolts held in
place by some kind armature, maybe you're right.

In my experience, cast lead keels are alloyed with antimony, which makes
it take a thread very well. The place for the keelbolts are drilled &
tapped (using a jig), then the bolts put in.

I have also seen conventional bolts put up through the keel stub via
recesses molded into into the keel, the recesses are then filled with
putty. Then there's the technique (used in a couple of the lower priced
mass-produced boats of the early 1970s) of welding the keelbolts in a
'T' and casting them into the keel. The method you describe is sort of a
variation, I can easily believe it's done but haven't seen it myself.

Fresh Breezes- Doug King

DSK wrote:
They can be removed. That's what the threads do.



Steven J. Ross wrote:

I believe he means from the keel itself.


So did I


Regards
Doug King


If the bolts were bent and cast into the molten keel, you will not
remove them. You should find out the breaking strength of the bolts
and then do not exceed this torque when trying to remove the nuts or
bolts. If you get up close to breaking torque for your bolts and
they don't come out and they don't break they are ok. Hell, If they
get up to 75% and don't give, I'd trust them.

If you break one, you've got to do them all.

If they need to be changed, you might cut them out with a torch or
saw, and re solder the keel top sections around the replacements,
which you will position with very carefully crafted jigs tack
soldered on, then cut off afterwards.

Should keep you busy for the weekend. Older bodymen and plumbers
have experience with lead filling, using a naptha blowtorch. Old
cast iron pipes were often caulked with molten lead.

Good luck

Terry K

On Thu, 26 May 2005 00:41:47 -0300, Terry Spragg
wrote:


If the bolts were bent and cast into the molten keel, you will not
remove them. You should find out the breaking strength of the bolts
and then do not exceed this torque when trying to remove the nuts or
bolts. If you get up close to breaking torque for your bolts and
they don't come out and they don't break they are ok. Hell, If they
get up to 75% and don't give, I'd trust them.
///
Terry K

This certainly sounds like uncommonly good advice.
Unfortunately, it is not practical - something of a day dream in fact.

Engineers find great difficulty in relating tightening torque on a
well-characterized fresh nut and bolt to its allowables or breaking
strength - but when it comes to a submerged, possibly corroded
fastener, you will be hard pressed to compute a torque value that is
within a factor of three of the actual value which snaps the shank.

Brian Whatcott Altus, OK