Antifouling for Aluminium Boat

[terradagua]

Hi,

Could anyone tell me about their experience with antifouling on aluminium sailboat. We tried Castellano last year and are not so impressed, we could try something else this year. On the shop over here, I have the choice between Nautix A1 Aluminium or Trilux 33. Anyone has tried them on the alu boat?
thanks a lot in advance!!!
Claudia

[David M]

The thing is there is little choice and all the choices are poor. None work for very long. I have been through the whole gamut myself. I use Micron 33 which seems to be the least worst. Where my boat is located it works for maybe 2 months before the photozone of the waterline needs to be scrubbed. After that it needs to be scrubbed perhaps once every two weeks. I usually let it go and not worry too much about it, so I do not end up scrubbing all of it off of the boats waterline.

I know of one person who put multiple layers of epoxy on his aluminum hull and then applied copper bottom. But this is really risky business and I do not recommend doing this. One ding in the epoxy and severe electroysis can start.

[barnakiel]

We tried trilux on GRP. I would not use it again.

b.

[barnakiel]

BTW We also tried Petit (Petite?). It was equally bad.

b.

[crabbymartin]

Have used Trilux found it poor so after advise tried Seagem so much better would recommend it to anyone.

[fstbttms]

Interlux Micron 66 is an excellent hybrid ablative paint and can be applied over properly prepared aluminum.

[noelex 77]

Originally Posted by fstbttms

Interlux Micron 66 is an excellent hybrid ablative paint and can be applied over properly prepared aluminum.

Please don't use Micron 66 on an aluminium boat

To quote international paints
* After suitable priming is suitable for use on all substrates, EXCEPT ALUMINIUM
(their emphasis not mine)

Even zinc rich primer coats and epoxy barrier coats do not render this safe.

[atoll]

you might want to look at this next generation stuff,expensive,but if you get 6 years out of it,it works out quite cheap

SIGMAGLIDE® 890 » Sigma Coatings - Marine, SIGMAGLIDE, ultimate fouling system

[fstbttms]

Originally Posted by noelex 77

Please don't use Micron 66 on an aluminium boat

To quote international paints
* After suitable priming is suitable for use on all substrates, EXCEPT ALUMINIUM
(their emphasis not mine)

Even zinc rich primer coats and epoxy barrier coats do not render this safe.

I stand corrected.

Suitable for aluminum- No

Antifouling Paint For Boats & Yachts | Interlux

[bottompaint]

The issue with bottom paint over aluminum is that most bottom paints contain copper. Copper reacts with the aluminum (creates a battery) and therefore you need an extensive primer barrier system (6-8 coats of high build epoxy and 2 coats of a strontium chromate primer (for a total of at least 25mils). Quite extensive, quite expensive.

Therefore, the solution by bottom paint manufacturers is to offer copper-free bottom paint. i.e Trilux. However, they do not perform as well as traditional copper based bottom paint. You dont have to worry about them reacting to the aluminum, but they just dont perform well.

The best solution I have seen out there is Smart Solution by Sea Hawk Paints. I have heard of great results compared to the other copper free bottom paints! Much better performance than Trilux. However, you do have to clean the boat because it does get soft growth (slime)...but no hard growth. I know you can put it over your existing bottom paint. They dont claim 6 years...just the normal year or 2 like all bottom paint.

[FatBear]

I keep an aluminum boat in a boat house in fresh water (in Oregon). My big problem is slime and stringy vegetative growths, not barnacles and such.

Originally Posted by atoll

SIGMAGLIDE® 890 » Sigma Coatings - Marine, SIGMAGLIDE, ultimate fouling system

Is this paint available in the US? Where? Is it available in small quantities? Their website only shows giant ships.

Originally Posted by bottompaint

The best solution I have seen out there is Smart Solution by Sea Hawk Paints.

It seems that this paint is salt water activated, which would preclude it working for me. Their Mission Bay line is UV activated, but I doubt that I get much UV inside of a boat house.

Any suggestions for me? Thanks.

[FatBear]

Tony Bulpin from Sea Hawk paints sent me a brochure for their 4700 series Smart Solution paint which says nothing about salt water activation. He says some slime will grow but that it will wash away with use and that it is easy to wash off when the boat is hauled. It goes on over old paint as long as it's in decent shape. I think I will give this stuff a try.