aluminium prep

[oz_hole]

Got a bit of fairing to be done to a section of aluminium below the waterline and was looking for for some advice on products etc.
Thanks, Oz

[peterpan2k]

Hi
Prime with zink cromate.
Jim

[WHOOSH]

Oz:

Zinc Chromate is ok as a generic metal primer but IME not the best solution for aluminum. I''ve had good success using Vinyl-Lux 2-part etching material from International on a number of aluminum-coating projects (vane, windlass case, deck plates).

However, you''re asking a lot when trying to seal an aluminum structure underwater simply by painting it. You''ll need a product designed for permanent sealing. I''ve always had great experience with the Tech folks at International - why not give them a call and put the exact circumstances before them. You''ll get a more comprehensive, field-based answer than any of us are capable of.

Jack

[able snead]

I helped Peter Limmer , A Kiwi Yacht painter, fair and paint my hull, A 44 foot aluminum schooner. SO far it is the fairest hull I have encountered. We used 9031 awl product primer- basically there formulation of zinc cromate. The primer was applied over an 80 grit grind, within 2 hours of the grind, obviously small sections. The primer was coated with 2 coats of 545 high build a n awl grip product. the fairing was at first their polyurthane filler mixed on site with micro beads . Nearer the final fairing coats we used premixed filler. IT was hughly expensive, and took 3 months of almost every day. I could not know imagine the boat any other way ( the hull is dark purple, and awl grip color , and still fairer than any other I,ve seen