I am considering options for protecting some welded steel objects from corrosion. These will be buried in soil (a mixture of silt, clay and gravel) and will at times experience some considerable forces both up and down which could possibly damage the protective layer(s). (For those curious, these are feet for timber piles for a solar panel sail which will be pulled up or pushed down depending on the wind direction).
Hot-dip galvanising would have been ideal but is not practicable (the feet are bulky, heavy and I don't know where, how much etc.)
So, my initial intention was to just coat them with CRC Zinc It.
Recently one guy suggested Fishoilene instead. This looks like a good alternative for a thing to be buried, but I am not sure whether it then can (or need to) be painted over.
Fishoilene "will gradually set to a pliable protective coating. Not recommended for overcoating" — as the tin that I've got says. But "pliable" coating doesn't sound like something that can withstand gravel pressing it: it would perhaps give in and expose the steel to the wild.
Then, "overcoating" here is a bit confusing. Does it refer to applying Fishoilene over an existing coating (as opposed to over bare metal/rust)? Or does it refer to applying some other coating over Fishoilene afterwards?
Can/should Fishoilene be top coated with something (e.g. Heavy Duty Primer)?
Interestingly, the Fishoilene spec does not mention any seal/finish options, whereas the spec for Cold Galvit (an alternative surface preparation stuff) does recommend some seal/finish products. From this I infer that Fishoilene is supposed to be the one-and-only coating, and then one needs to be gentle with the coated objects as the coating is "pliable".
Does that sound about right? Or can someone testify that Fishoilene can successfully be painted over and reinforced?
Thanks in advance!