What paint should I use???

[geoffr]

I'm looking to find some paint for some metal and plastic underwater parts on our sailboat as we are completely re-doing everything underwater. We are currently in freshwater north of the great lakes, but will be heading back to the Caribbean. The hull is currently being painted (from bare fibreglass) with Interprotect 2000E and then Micron CSC (and later with 66 when we are in salt water).

#1 Outdrive
I have sandblasted the aluminum outdrive and am wondering what paint to use. The top half is always out of the water, the bottom is in the water at anchor and underway (out at the dock). I could use an antifouling or another paint.

#2 Bow Thruster case
We have a bow thruster which has a bronze case which has never been painted... (it's brand new)

#3 Bow Thruster prop
The prop on the bow thruster is plastic..


For #1 and #2 I have looked at interlux and am a bit confused as they no longer seem to have an etch primer and recommend a thinned Interprotect.. which just sounds wrong! Petitte look to have a number of solutions. I'd be okay with all Petitte for the outdrive, but the for the Thruster I'm wondering if I use their etch, then Interprotect and CSC would work so it is the the same as the rest of the boat.

#3 - ideas?

thanks,
Geoff.

[Boatyarddog]

TBT paint in an aerosol can for the out drive maybe unavailable till you get south, or alternatively Interprotect 4000, Barrier coat, no copper Bottom paint on Aluminum. Try the no copper based Eco paints, over sanded Interprotect 4000.



Sent from my iPad SV Cloud Duster

[geoffr]

After looking at the effort/number of different can's of paint I'll need with Interlux or Pettit I'm thinking of a simple outboard paint system (2 cans)..

Moeller Marine Online - Marine Paints

[David M]

Interlux 2000 can be applied directly to all metals. You want to apply it to bare metal with little to no oxidation. I use it as a barrier coat on my aluminum hull and steel rudders. Put it on thick on aluminum so that it is more resistant to dings which can start the blistering process. There is no coating for aluminum which stops the blistering process once you get a ding in the paint.

Interlux 4000 is a harder epoxy and is therefore a more brittle epoxy. It is less appropriate as your initial coating over bare metal.

With copper bottom paint you absolutely have to cover all the aluminum with multiple barrier coats and keep up on the anodes for the aluminum.

I would put a tougher coating such as Interlux 2000 epoxy over the overboard spray paint which is not an epoxy.

[geoffr]

David,

The bare metal is my problem - there are many nooks and crannies on the outdrive that by the time I sand it down I'd need to start again (a factor of the time I have available and the time to sand). Did you sand to bare metal with little to no oxidation?

It seems better from what I'm seeing to use an etch primer (which Interlux used to have but stopped making) - I'm thinking: Moeller Marine Online - Primers

I do however agree with interprotect 2000 as it's a nice rubber like coating when done.

[minaret]

Try Velox.

[geoffr]

I've decided to go with Moeller..
I've used the primer (4 coats) and the base color (3 coats) and so far looks good. Needs a bit of sanding of the sags and a few more coats. Dries quite quickly if you make it a nice and thin coat.
As I did not use an epoxy fill so it won't be perfectly smooth.