Lead bricks for ballast in our steel hull

[Make_My_Day]

We have a Carena 40 Dutch built steel ketch. The keel itself contains 4 tons of lead as ballast. Until now we have had no problems. However in the forward section of the bilge, there are many lead bricks. I assume these were added for additional ballast.
I noticed corrosion on the surface of the steel. I was removing the lead in order to prep and coat the steel. The problem starts as the last of lead bricks (those on the bottom) are stuck fast to the steel. I'm no metallurgist but I assume this galvanic corrosion.
These bricks are really stuck. Any ideas on how to break them free without inflicting damage to the hull? Or should I just leave them as they are so hard bonded?
Any help here would be greatly appreciated.

[billknny]

You need to remove them.

If you are thinking that the steel under them is damaged to the extent that removing them could damage it , then you REALLY need to remove them!

Nothing on a boat gets better because you ignore it. That goes double for corrosion on the inside of a metal boat.

[Make_My_Day]

Originally Posted by billknny

You need to remove them.

If you are thinking that the steel under them is damaged to the extent that removing them could damage it , then you REALLY need to remove them!

Nothing on a boat gets better because you ignore it. That goes double for corrosion on the inside of a metal boat.

I figured as much but checking. Any ideas on how to get them loose.

[billknny]

Crowbar and hammer. If they were glued down, heating them with a torch will help.

If they were not glued down, think about the damage they could cause loose in the boat in a knockdown!

[Jammer]

16 or 24 pound sledge, hit on the side of each brick as hard as necessary to get them loose


Failing that use heat


With the boat on the hard you could heat the hull from the outside


Be careful of the obvious hazards, particularly the fire hazard and the need for breathable air if you are heating them in an enclosed space. I would use an SCBA.


If they have been epoxied you will not get them off without heat


But if they have been epoxied in place properly you may not wish to remove them once you confirm that they are safely attached and there is no corrosion

[Make_My_Day]

Originally Posted by Jammer

16 or 24 pound sledge, hit on the side of each brick as hard as necessary to get them loose


Failing that use heat


With the boat on the hard you could heat the hull from the outside


Be careful of the obvious hazards, particularly the fire hazard and the need for breathable air if you are heating them in an enclosed space. I would use an SCBA.


If they have been epoxied you will not get them off without heat


But if they have been epoxied in place properly you may not wish to remove them once you confirm that they are safely attached and there is no corrosion

Thanks for the tips. I never thought about the possibility of them being epoxied in place. 90% came out with little or no persuasion. Some had rust on them so I concluded that they were corroded in place.
If epoxied in place, wouldn't they all be epoxied or just the ones in contact with the hull?

[Cheechako]

Sometimes Zinc bricks are used. Are they Zinc or Lead I wonder? Zinc is very close to steel on the galvanic series, Lead is not.

[Gaia]

We lined our (epoxy painted) bilge on our Gazelle GAIA with formica before inserting made to fit lead bricks and then bolted those down with threaded rods before sealing the bilge with ss cover plates. Forward where the bilge tapered we fitted lead and then poured in hot wax. No problems in 24yrs.

I would consider for the OP's problem after rust removal and painting to pour in epoxy over the reinserted lead but you have to avoid large quantities at once either during preparation or in voids due to the exothermic reaction. The heat generated must be able to escape although the mass of lead and steel will help. If the lead fits well there should not be a problem. Better than cement I think but more expensive

Jim

[lvictorlucas]

If you are worried that the entire thickness of the steel hull has been compromised I would suggest placing a cheep blue tarp on the outside of the hull in case their are some pin holes. Also any non constrained heavy objects in the bilge could lead to stability issues either by changing the center of displacement or resonance. When you put them back place an open weave plastic mat under them for airflow and electrolysis.

[Make_My_Day]

Thanks for the tip. Not worried about hull thickness. I had it measured not too long ago. It is really some ugly surface corrosion that I want to address before it becomes a problem. The mat is a good idea.

[Make_My_Day]

Originally Posted by Gaia

We lined our (epoxy painted) bilge on our Gazelle GAIA with formica before inserting made to fit lead bricks and then bolted those down with threaded rods before sealing the bilge with ss cover plates. Forward where the bilge tapered we fitted lead and then poured in hot wax. No problems in 24yrs.

I would consider for the OP's problem after rust removal and painting to pour in epoxy over the reinserted lead but you have to avoid large quantities at once either during preparation or in voids due to the exothermic reaction. The heat generated must be able to escape although the mass of lead and steel will help. If the lead fits well there should not be a problem. Better than cement I think but more expensive

Jim

Thanks for the ideas. Still trying to figure out how to get the last ones loose. They are stuck in really good.

[S/V Alchemy]

I have Torino lead ingots on our steel boat as trim ballast. They are not epoxied but simply laid like interlocking bricks between frames and stringers. I have noticed no corrosion in that area, but for obvious reasons, I'm moving them either off the boat or to a spare tank (former holding tank) in the keel where I can epoxy them into place and/or plate over that tank should I want that ballasting after water tanks get filled.


Consider getting a chain fall to move the ingots any distance.

[boat driver]

Zinc or lead, if they are such, the corrosion is not the blocks but the steel in the void area.
If the bottom of the front of the keel could suggest anything from epoxied in to previous keel damage and repair (without removing the ballast) therefore melted into- to having as well fasteners from the bottom up into the ballast as a method to secure the ballast into the hull.
How old is the boat?
is the builder still available?

[MoorOrLess]

Not sure heat on lead is the best direction. The lead will turn molten quickly. It doesn’t take much flame to change from solid to liquid.
It was not unusual to add lead bricks to increase righting moment. I haven’t seen it done on a steel boat, but on plastic boats they were glassed in, so I would expect these are glued or bolted in place. Are there two of them stuck either side of a floor? Might be a threaded rod or steel spike through the floor.
Perhaps a brick layer’s chisel between the steel and lead to pry apart.

[Make_My_Day]

Originally Posted by boat driver

Zinc or lead, if they are such, the corrosion is not the blocks but the steel in the void area.
If the bottom of the front of the keel could suggest anything from epoxied in to previous keel damage and repair (without removing the ballast) therefore melted into- to having as well fasteners from the bottom up into the ballast as a method to secure the ballast into the hull.
How old is the boat?
is the builder still available?

The boat is from 1980 and the builder is no longer around. Thanks for the feedback