Recently I was returning from a day out visiting job sites on Block Island, when as I was boarding onto the ferry, I almost had a heart attack!
It was a simply gorgeous November day and apparently one of the ferry maintenance staff had been tasked with painting a number of rusting support columns which happened to be right near the dock I was getting onto.
I literally almost passed out and fell off the dock, to be swallowed into the harbor below me, when I saw the fellow painting directly on top of rusted metal – I actually cringe thinking about it as I write this!
While there certainly are products that you can paint directly on top of rusted metal without a problem – assuming the surface is prepared properly first, which I can assure you, this was far from done correctly in this case! – these types of products are typically of the commercial paint nature and are most often epoxy-type coatings that you have to mix one part with another part in order to create a chemical reaction which allows you to have a product that is able to be painted directly on top of (assuming the rusted surface is properly prepared).
The correct order of painting heavily rusted metal should really be as follows:
– Be sure the surface you are painting is properly cleaned
– Prep all surfaces to get rid of as much rust as possible
– Prime the surfaces first with a primer that is specifically meant for heavily rusted metal (one that will lock in the rust and prevent it from bleeding through the finish coat)
– NOWWWW you can apply your product, which should be one that is meant to be used on surfaces that are prone to rust, and which has elements woven into them that intrinsically guard against rust
As shocked as I was to see the gentleman painting the heavily rusted columns – directly on top of unprepared rusted surfaces – I acknowledge that this type of scenario happens quite often.
It seems that it is not unusual for folks – both at the workplace and at home – to be sucked into the notion that products with the moniker ‘Use To Prevent Rust’ can be used directly on top of rust.
Even if the surface is properly prepared, the idea behind these products is for them not to be used directly on top of a surface that is showing any signs of rust.
The most proper approach is to get rid of as much rust as possible, then locking any remaining rust/rust residue in with the proper product, and ONLY then utilizing one of these rust resistant finishes.
If the surface is not properly prepped & primed with the right product, it is simply a matter of time before the rust begins to leach through the finish (even when the finish itself is noted as one that ‘Resists Rust’), and someone begins scratching their head wondering to themselves, “Didn’t I just paint that?”
For in these types of situations the rust rises up from beneath, similar to when rotting wood begins to show its face, these types of things occur from the inside out and when it does happen, it is no surprise to anyone that may learn how the process went about in getting it painted, even if it was done by a well-meaning dockhand on a fabulous November day that in and of itself was splendid for painting.
