[Pete_89T2]

Well I finished using the POR-15 starter set to deal with the rust & stripped paint problem discussed in post #1 of this thread. So here is my POR 15 review & update. BLUF is POR-15 and the associated prep products that came with the starter set are great products, and not all that difficult to use if you can follow some simple directions.

The starter kit can cover an area of up to 6 square feet, which was more than enough for my little job. It came with a 4 ounce can of POR-15 rust preventive coating, an 8 oz. bottle of "Marine Clean" cleaner/degreaser, an 8 oz bottle of "Metal Ready" metal prep solution, a pair of heavy duty latex gloves, 2 paint brushes (1 foam, 1 bristle, about 1 inch wide each), and an instruction sheet plus a magazine-style catalog that describes the rest of the POR-15 product line up and provides some handy how-to info. I picked the semi-gloss black POR-15, the other choices are gloss black, silver & gray, IIRC.

In my case I was dealing with both bare shiny metal (stripped by brake fluid) and some surface rust spots. Reader's digest of the process is:

(1) Wire brush/sand off any loose paint scale & flaky rust if applicable -- just the loose stuff - you don't need to bring it down to bare metal
(2) Clean & degrease thoroughly with the Marine Clean solution, rinse with water & let dry.
(3) Prep the cleaned bare or rusty metal surfaces with "Metal Ready"
(4) Paint cleaned & prepped surfaces with POR-15 rust preventive coating (2 thin coats recommended)
(5) Optional but recommended - topcoat with paint of your choice. The one weakness of POR-15 rust preventive coating is that the pigments will eventually discolor if regularly exposed to UV light, hence the need for a topcoat.

For the cleaning phase, you dilute the Marine Clean with water. They recommend using no more than a 1/1 ratio (Marine Clean/water) but less concentrated solutions up to 1/10 will work on lighter filth. Hot water improves the effectiveness, so it's best to only mix what you need when you need it. Or if you choose to mix a batch in bulk, store it in a container that can be immersed in hot water to heat it up just before use. I was very impressed with this stuff, it worked better than any cleaner/degreaser I've used in the past to clean parts (i.e., brake cleaner, Castrol Super Clean, kerosene, etc), and I had plenty left over to clean other things. I used it to clean the carbon crud off the insides of my UIM & LIM and it literally dissolved that stuff in no time.

Once the cleaning is done and surfaces are dry, you apply the Metal Prep solution full strength with a bristle brush. You keep the surfaces wet with Metal Ready for 20~30 minutes, then thoroughly rinse off with water. Metal Ready is acidic, so it etchs the bare metal & painted surfaces just enough to give them a bit of "tooth" for the POR-15 to adhere to, and it leaves behind a zinc phosphate coating.

When the surface is bone-dry, you can start applying the POR-15. I used the foam brush for that, and did the 2 thin coats as recommended. POR-15 needs to be applied in temps between 50~80, and it actually cures faster in high humidity - opposite of most paints. Anyway, you can apply the 2nd coat after the first coat is a bit tacky but firm (i.e., you won't leave fingerprints on it, but you can feel the drag if you run a finger across the surface). It took about 4 hours between coats, but my garage was probably below the recommended temp when I applied it, around 40~45*F. When the 2nd coat of POR-15 was fully cured (I gave it an overnight), I used some black engine enamal to topcoat it. The pictures are the "after" result, see post #1 to this thread for the "before" shots.

Regarding durability, I decided to test POR-15's hardness claims. I painted a small piece of 1/8 thick scrap AL stock with the 2 thin coats. After it fully cured, I put the AL strip on a small anvil and started whacking it with a ballpein hammer -- I could not get that stuff to crack, chip or flake off; even after mashing the AL thinner than it's original 1/8" thickness, the POR-15 stuck to the AL substrate without compromise.