Painting the different parts of my bottom...

[Kelpie]

So, the new (to us) boat has arrived. First job is a lift and hold next week to get the stuck centreboard swinging as it should, and to apply the necessary primers/AF to the various underwater surfaces.
The hull is GRP so no worries there, the bolted on keel is lead which is new to me- I guess a good compatible primer is my friend there.
The tricky part is the centreboard. The seller told me it was bronze, but documents with the boat suggest that it may be galvanised steel.
I have been in touch with the owner of the same type of boat, and was relieved to hear that fouling on the centreboard was minimal, presumably due to the absence of light when it is retracted into the slot. However it seems sensible to put some sort of AF on there.

The problem is finding a primer and AF that are compatible with these metals- very few brands mention bronze, and the tins of AF I have already got are not compatible with galvanised steel. Will a good barrier coat allow me to put whatever I want over the top, or is that asking for trouble?

 

[Rigger Mortice]

It won't be bronze.

 

[oldsaltoz]

I suspect a few coats of solvent free epoxy followed by a sand down and coats of epoxy primer will allow you use whatever takes your fancy.

Good luck and fair winds.

 

[William_H]

Cast iron is very common for fin keels. There is not a problem of incompatability but rust is a real problem. Not that the rust really damages the keel but it expands and pushes of the a/f paint so opening up a place for weed growth. The asmwer for you as said is an epoxy over the steel plate after cleaning and treating any rust areas. Then a/f paint as used on the hull. needless to say you must not build up too much on the keel or it will be difficult to retract.
As you suspect you won't get a big growth problem ojn the retracted keel due to no light. good luck with the new boat olewill

 

[jwilson]

It won't be bronze.

It might well be: bronze centreboards were fitted to some (often American) quality boats, and this one has a lead keel, an indicator that she was not built with the cheapest materials.

 

[[70521]]

If it is bronze remove the keel and replace it with a cheaper material. You should be well in pocket.

 

[Lakesailor]

Does a magnet stick to it?

 

[Kelpie]

Finally got the boat lifted today. It is indeed a big lump of bronze. Very little fouling on it, I wonder if I should bother antifouling it at all?

 

[mrming]

Finally got the boat lifted today. It is indeed a big lump of bronze. Very little fouling on it, I wonder if I should bother antifouling it at all?

Couldn't tell you about the bronze, but just to satisfy my curiosity, what kind of boat is it?

 

[Kelpie]

Couldn't tell you about the bronze, but just to satisfy my curiosity, what kind of boat is it?

A Deb 33, built by Deacons in 1970, designed by S&S. I'll put up some pics once she's looking a bit tidier!

 

[vyv_cox]

I have experimented a little with painting manganese bronze, possibly not quite the same as your bronze but certainly copper based. The best by far has been Hammerite Special Metals primer. I have to say I am pretty impressed by this stuff, good adhesion to my Autoprop, which may be bronze, P-bracket, probably Mn bronze, and even my stainless steel prop shaft. It easily survives a season underwater and seems to provide good adhesion to subsequent coats of antifouling.

 

[Kelpie]

Thanks for that Vyv! Will see if I can pick up a tin tomorrow.