Lead on steel connectivity an issue?

[LeoKa]

I am working hard on a very nasty job at the bilge level. The area is tight and hard to reach, but I have progress.
The first owner/builder put large amount of lead bricks into the forward section of the bilge. It is almost impossible to move them. They are very heavy.
I discovered that each lead brick has a rubber/plastic sheet between the steel hull and the lead. I do not know, if this serves as slide preventive measure, or is it an electrical insulation? This sheet is about a 1/4" thick and hugs each brick around.
During this cleanup process, I had to move some of the bricks away from the lowest point, so I can vacuum out the area properly. This way, some of the bricks now sitting on the steel directly, without any in-between insulation. As I move forward towards the bow, the lead does not have any insulation there. Only the huge and heavy bricks around midsection.
Is this a problem? Do I need an insulation between lead and steel? I'd prefer to leave the bricks alone, since it is very difficult to work in the area, but I do not want to start some type metal-metal electrical corrosion, or such. Am I worrying too much and there is no issue with this? Or, I do need to separate the lead and the steel from each other?
Please, advice.
(I am in a fresh water marina now on the Colombia river. My anodes are almost the same for second years now)

 

[SteveK]

Interesting question, so I asked google. It seems lead could corrode and the steel will not be harmed.
The rubber feet then as you said must be to avoid movement.

On a side note, you must be bored to have taken on this cleaning job.

 

[LeoKa]

Interesting question, so I asked google. It seems lead could corrode and the steel will not be harmed.
The rubber feet then as you said must be to avoid movement.

On a side note, you must be bored to have taken on this cleaning job.

Lol, so true. I love this type of work. So, I put it aside for the last two years now. Unfortunately, I have install a new floor, after removing a carpet cover, and I am tired of walking on plywood. So, it has to be done, but it is nasty. My grey water tank used to leak into this area. It is fixed now, so time to clean it and dry it out. This was the reason of the lead exercise.

 

[Fleming]

Interesting question, so I asked google. It seems lead could corrode and the steel will not be harmed.
The rubber feet then as you said must be to avoid movement.

Another failure for AI.
Lead is much more noble than steel, so the lead would be fine (cathode) and the steel would be the anode in that galvanic circuit.
In general lead is not usually too problematic, that's why we can keep stainless bolts inserted in it for 30 years often without issue, and being in freshwater your risks of galvanic corrosion are also less. Still, I wouldn't want any more noble metal touching any of the steel on my boat. I would think it worth the effort to get back in there and insulate it.

 

[luna]

I googled this as I did not where the two metals are placed on the Nobility chart. It seems I'm not alone as on some charts Steel is more noble, least active, less likely to corrode and on other charts Lead is more noble. Humphf!

Regardless, I sure hope you are wearing a suitable form of personal protection as lead can kill you, it's simply a matter of how much you have inside. All of the lead that your body takes in during your life will still be in your body at your demise.

Take Care.

 

[Mako]

I've never seen lead bricks, on any boats including big Hatterases, ever secured. Probably not an issue in 99% of the cruising most people undertake, but I can think of storms I've been hit by out in the ocean where our 30° rolls would put a vessel with loose ballast in danger.

OP your boat looks like it is a great long range cruiser, so have you thought about tack-welding some steel straps or bars to secure them?

 

[Comodave]

Be careful vacuuming around it. The lead can flake and the shop vac could spray the lead dust all over. Lead is very hazardous, ask the residents of Flint, MI. I did use lead ingots in a previous boat for ballast but I glassed them in so they wouldn’t move and to contain any dust. I think they were 66 pounds if I remember correctly.

 

[LeoKa]

Regardless, I sure hope you are wearing a suitable form of personal protection as lead can kill you, it's simply a matter of how much you have inside. All of the lead that your body takes in during your life will still be in your body at your demise.

Take Care.

I was not messing around with the lead bricks much. I just had to move two of them about 10 inches aside. I had to use prying bar to move these suckers. My hands were useless for this, but I had gloves on anyway.
The vacuuming was only for the leftover gray water and some hydraulic oil, which were permanently residing in this area for a while. The goal was to have access to the deepest section of the bilge, where these liquids accumulated.

 

[LeoKa]

I've never seen lead bricks, on any boats including big Hatterases, ever secured. Probably not an issue in 99% of the cruising most people undertake, but I can think of storms I've been hit by out in the ocean where our 30° rolls would put a vessel with loose ballast in danger.

OP your boat looks like it is a great long range cruiser, so have you thought about tack-welding some steel straps or bars to secure them?

I am sure that was the original builder's intention. Those bricks were even glued together with something, so it took me a while to separate them. It was a nice discovery challenge job.
The bricks are under the floor 1-2 inches away, so not much movement is possible for them. Luckily, the Colombia river does not create wakes for 30 degree rolls. But who knows? As jet-skies grow larger and larger, one day it could happen. We have plenty of those racers here on a nice sunny day. I have no plans to go out to the ocean anytime soon. Aging....

 

[LeoKa]

Still, I wouldn't want any more noble metal touching any of the steel on my boat. I would think it worth the effort to get back in there and insulate it.

You are correct. It can't hurt. The project will last for a while, so I can buy and install something to insulate those two bricks.

 

[SteveK]

lead ballast was used 50+ years ago, about the same time as asbestos.
What were our parents thinking?

 

[LeoKa]

lead ballast was used 50+ years ago, about the same time as asbestos.
What were our parents thinking?

My boat was originally launched in 2000, so old habits die slowly.

 

[Portage_Bay]

My boat was originally launched in 2000, so old habits die slowly.

You can put my response in the for what it's worth column. I used to run a steel boat with tons of lead ingots in the bilge for ballast. 80 lbs each. They were not secured in any way. Just lay between the frames. We went through extremely heavy weather. They never shifted.

After many years the paint in the bilge was beginning to fail. The ingots were removed for recoating and replaced. There was no indication of corrosion of either the steel or lead.

It was brutal work. I was a younger man then.

 

[LeoKa]

You can put my response in the for what it's worth column. I used to run a steel boat with tons of lead ingots in the bilge for ballast. 80 lbs each. They were not secured in any way.

How the hell did you move an 80 lbs ingots out of the bilge?
Thanks for the encouragement.

 

[Delta Riverat]

Metallic lead is quite safe. It's the compounds that are dangerous.

 

[Portage_Bay]

How the hell did you move an 80 lbs ingots out of the bilge?
Thanks for the encouragement.

I probably had more room to work than you, it was a space big enough I could crawl around in.

 

[CharlieJ]

Well, I can’t let this Teaching Moment go by!

Per ABYC E-2 Cathodic Protection; Table 1 Galvanic Series of Metals in Seawater with Reference to Silver/Silver Chloride Reference Cell:
Mild Steel has a freely corroding potential of: -600 to -700 mVDC (active end of the chart)
Lead has a freely corroding potential of: -190 to -250mVDC (noble end of the chart)

In this galvanic couple, mild steel is strongly anodic (will corrode) to lead (will be protected) when electrically connected (simply in contact) and immersed in sea water. The same relationship would be present in freshwater, however, the absolute voltage levels would be much reduced.

If it were my boat, I would not allow the lead bricks to be in direct contact with the steel hull plating.

 

[LeoKa]

If it were my boat, I would not allow the lead bricks to be in direct contact with the steel hull plating.

Alright, I will get a rubber mat from the local store and squeeze under the lead somehow. Fairly cheap solution to be on the safe site.