Lead Keel

[Javelin]

I have a lead keel, which I've coated with Primocon ready for antifoul.

Then I thought, why do I bother to coat it at all?
It's lead, it wont rust and I'm sure your average Barnacle wouldn't like it too much either.
So apart from it being arguably non-environmentally friendly is there any other reason why I should coat a lead keel?

 

[Aurai]

Mr, Mrs and all the Barnacle family do seem to love it!

 

[TimBennet]

Mr, Mrs and all the Barnacle family do seem to love it!

They do indeed. Primocon won't harm, but antifouling is essential.

 

[lpdsn]

Mr, Mrs and all the Barnacle family do seem to love it!

It does lower the educational achievements of the family though.

 

[Downsman]

It does lower the educational achievements of the family though.

Encrusted with dense Barnacles..Nothing worse..

 

[dratsea]

Primocon sticks to lead for about a season. I am told I need to acid etch first.

Dratsea

 

[AntarcticPilot]

I have a lead keel, which I've coated with Primocon ready for antifoul.

Then I thought, why do I bother to coat it at all?
It's lead, it wont rust and I'm sure your average Barnacle wouldn't like it too much either.
So apart from it being arguably non-environmentally friendly is there any other reason why I should coat a lead keel?

Metallic lead is environmentally OK; in salt or hard waters it forms a thin carbonate layer on the surface that then isolates it from the environment. Lead pipes are actually perfectly OK in areas where the water supply is hard, and you won't die quickly even in a soft water area. The Decline and Fall of the Roman Empire might have had something to do with the prevalent use of lead pipes for water, as some have suggested, but it didn't cause mass mortality! So a lead keel is unlikely to have any impact on things growing on it.

I will admit that I may have the chemistry wrong - I'm depending on knowledge I gained when I was in my late teens - but the general principle is correct; metallic lead is in itself not poisonous enough to act as an anti-fouling.

 

[TimBennet]

Primocon sticks to lead for about a season. I am told I need to acid etch first. Dratsea

Not strictly true and certainly acid etching is not the industry norm with keels. International say that a good mechanical key is sufficient when painting lead. I would also skip the Primicon and antifoul direct.

However, if you want to 'fair the keel' then a mechanically prepped lead keel will happily accept two part fillers directly.

 

[KellysEye]

Lead keels are normally encapsulated in GRP or steel and not directly exposed to water so antifoul is needed. GRP doesn't need a coating steel needs zinc rich epoxy before antfouling.

 

[TimBennet]

Lead keels are normally encapsulated in GRP or steel and not directly exposed to water so antifoul is needed. GRP doesn't need a coating steel needs zinc rich epoxy before antfouling.

Only in some parallel universe. Here on earth, the vast majority are plain cast lead, exceptionally they may be GRP coated for 'fairness'. But encased in steel - well, we built some like that in the eighties for a client, but they were expensive follies that only the client thought were a good idea. I've never seen another example.

 

[KellysEye]

>But encased in steel - well, we built some like that in the eighties for a client, but they were expensive follies that only the client thought were a good idea. I've never seen another example.

We had a steel boat where the lead was encased in steel built by Tak Yachtbouw in Holland. At the time Tak built a number of yachts they were professional builders of ocean going tugs and the yachts were built to commercial standards.

 

[TimBennet]

We had a steel boat where the lead was encased in steel . . .

Well, the practice of melting lead into the keel cavity of a monocoque steel hull isn't quite the same as all "Lead keels are normally encapsulated in GRP or steel . . ."

For each steel yacht with melted lead ballast (and even including the one's with other fillers such as steel punchings, scrap iron and concrete), there must be many thousand times the number of production GRP boats with plain cast lead keels. Look at the photos on Mars Keels website to see rows and rows of them. Beneteau fitted 700 to them on the 40.7s alone!

 

[bitbaltic]

Lead keels are normally encapsulated in GRP or steel and not directly exposed to water so antifoul is needed. GRP doesn't need a coating steel needs zinc rich epoxy before antfouling.

Our lead keel is not encapsulated in anything.

 

[DanTribe]

I have a lead keel, which I've coated with Primocon ready for antifoul.

Then I thought, why do I bother to coat it at all?
It's lead, it wont rust and I'm sure your average Barnacle wouldn't like it too much either.
So apart from it being arguably non-environmentally friendly is there any other reason why I should coat a lead keel?

I was in the same situation a couple of years ago so sought the advice of the paint makers technical dept.
"what should I use on my bare lead keel?"
" We recommend 4 coats of underwater primer then 2 cts underwater undercoat"
" OK, is this to give a good surface for the antifouling?"
" Not really. It's to ensure a water proof coating to the keel"
" But it's lead!"
"exactly, otherwise the lead will absorb water and will go rusty"
At that point I decided there was no point in continuing the conversation.
I did give it the primer and undercoat treatment but really to provide a decent surface for the antifoul to bond.

 

[penfold]

Underwater primer and underwater undercoat; presumably the premium paid for the 'underwater' part allows submarine application, or is it just marketing rowlocks?

 

[DanTribe]

Underwater primer and underwater undercoat; presumably the premium paid for the 'underwater' part allows submarine application, or is it just marketing rowlocks?

This was Hempels / Blakes stuff. I probably mis-remembered the undercoat part, just underwater primer was recommended. Seems to be good stuff and has lasted 4 years so far.
Gives a good surface and acts as a tie coat for the antifoul. So it was probably good advice but for the wrong reason!

 

[PaulMcC]

Our lead keel is not encapsulated in anything.

Whereas mine is. 70s/80s build GRP encapsulated lead keel.