M/V Infinity

 

Rust Bullet is a single component primer (no primer/catalyst mixing) that can be applied with a brush, roller or spray. According to the Rust Bullet website, its patented technology beats POR 15 and it penetrates the porous rust reaching the metal underneath. If this is true for at least a subset of my applications, it deserves further investigation! I purchased 1/4 pint of their standard formula from their website for my trials.

 

It looked a lot like another product I used in the late 1990s: Pettit's RustLok primer. RustLok is also an aluminum-colored, single component polyurethane primer. I coated a number of steel hatch covers and motor brackets with RustLok in 1998.  All began to bleed rust faster than similar areas I painted with CeRam-Kote or a two component epoxy primer. Perhaps I did not clean the surfaces sufficiently, perhaps I applied too much material per coat, perhaps I did not apply enough coats, perhaps the product has improved over the last 10 years. I am hopeful that Rust Bullet will outperform my experience with RustLok.

 

Their instructions recommend that 6 to 7 mils of primer be applied via at least 2 to 3 coats. For marine use, 12 mils are recommended.

 

 

 

I selected a population of six rusting areas on the forward bulwarks for my trials. 

 

All areas were previously primed with a two-part epoxy primer, faired, primed again, and finally with a two part polyurethane was applied as the topcoat. The underlying rust has blistered the fairing, cracked the topcoat, thus allowing water to penetrate beneath the paint, further exacerbating the rust. I assume a pinhole allowed water to penetrate the protective layers of paint.

 

All areas were first cleaned with a needle gun to bare metal, then wire-wheeled, and finally wiped with acetone. I applied two coats of Rust Bullet about 4 hours apart with a 1" brush.

 

 

 

 

Two additional coats of Rust Bullet were applied. After drying the surface appears to be very hard, although not as hard as CeRam-Kote.

 

I need to manage my schedule more efficiently and apply 4 coats within a single day. In this case, I needed to spend time at my place of employment between coats.

 

 

 

Sand with 150 grit sandpaper, and prime with Sterling U-4747 high-build epoxy primer.