Hamilton Jet HJ212 Installation And Service Manual page 68

Maintenance
Bare metal refurbishment - steel and stainless steel
The area of refurbishment and immediate surroundings should be degreased with a water soluble degreaser
and thoroughly rinsed off with clean water.
Abrasive blast the surface clean to achieve a finish to Sa 2.5 (or to equivalents - AS1627.4 Class 2.5, NACE 2,
SSPC – SP10). Feather the edges back 20-30mm onto sound substrate. Appropriate masking is required to
ensure that pushrods, bearings and seals are not blasted and that blast media does not contaminate
bearings, bushes, and seals.
The surface should then be blown down or washed to remove sanding debris followed by a solvent wash to
leave the surface dry and clean. For parts finished with the grey gloss scheme, mask the remaining paint as
applying epoxy primer over the gloss finish is not recommended.
Within 4 hours (steel) or 1 hour (stainless steel) of abrasive blasting, a coat of steel surface primer must be
applied to seal the surface - refer to the manufacturer's specifications and recommendations for application.
If filling is required to repair the metal surface, apply a suitable marine epoxy filler. The filler should be
applied after application of the epoxy primer. Sand the filler to achieve a smooth surface and then apply a
further coat of epoxy primer over the filler.
The next step is to apply the primer/tie coat to provide further corrosion protection and good adhesion for
the top coat.
Finally, apply the appropriate top coats to the primed surfaces.
Application of topcoats to primed surfaces
Ensure the correct primer has been applied for the intended topcoat.
Ensure topcoat is applied within the minimum and maximum recoat times specified on the manufacturers
technical data sheet. For example, in order to achieve good adhesion to Interprotect it is necessary to apply
Trilux antifoul within 7 hours at 23°C. If the epoxy primer has been left too long prior to application of
antifoul, it will be necessary to abrade the epoxy primer and apply a further coat of epoxy primer.
If existing gloss paint areas had been masked for application of primer, then remove masking in preparation
for over-coating with the gloss finish.
When fully hard, the repaired area can be blended to the surrounding surfaces with 120 grit wet and dry
sandpaper used wet. Once the surfaces are blended satisfactorily, wash area with clean water and allow to
dry.
Apply a top coat of gloss or antifoul.
Do not apply copper oxide based anti-fouling paints.
Do not paint over the anodes.
Anti fouling Paints
8-6
Installation and Service Manual