Painting powder coated shutter hinges

Long story short: Got black powder-coated steel exterior shutter hinges. Originally, the project called for them to be painted a different color, so I sanded and primed them with Zinsser 1-2-3 spray. Later, color scheme changed (don't ask why) and project called for them to be black again. I noticed that the 1-2-3 didn't adhere fully to some parts. I am in the process of sanding it and use a razor blade to get rid of the not-so-fully adhered primer. In some very minor parts, the powder coat also scratched away when using the blade, but by and large almost all the powder coat is still there (much more dull due to sanding). I am now sanding with 120 grit -- no part is being left un-roughened up.

What paint should I use? I was thinking of using the Krylon Fusion for Plastic (satin black), "no sanding or primer needed" kind of productm which can be used in plastic, metal, even glass, and letting it cure. Or perhaps the Rustoleum Universal line. And then a spray can of the lacquer you find in a hardware store.

My logic is that, even if the pant gets scratched, the powder coat will be underneath, and being both of them black the scratch won't be noticeable. I am not using a separate primer to avoid too many coats, which is relevant in the pivot area to avoid scratching.

Any ideas? I am not planning to open and close these shutters frequently -- perhaps almost never - so friction shoulnd't be a problem. I am fairly limited to the Fusion or the Universal.

A solution would be to buy a new set of factory-powder-coated hinges, but I don't want to spend $100+ just so that I have greater scratch resistance on something I will hardly open/close.

 

One more thing: after doing some research, it looks like one can conclude the following
1) powder coating is a type of plastic
2) krylon fusion is specifically made to bond to plastic
3) It follows that krylon fusion would bond to powder coating

Any flaws in this logic?

 

I don't know a lot about powder coating but I've never heard it called a plastic
The few times that I've painted over a powder coat, I've sanded it well, wiped it with a liquid deglosser and then used an oil base paint [oil primer if the top coat is latex]

Most any solvent based paint/primer should adhere ok to a properly prepped powder coated item. The biggest concern would be how the new paint would hold up to the elements with fading being the main concern. I'd be leery of using lacquer over the paint - the 2 might not be compatible.

 

Could be wrong but my thoughts are the same as Mark - powder coating is a means of applying paint, it is not plastic. Do you actually have a plastic coating of some kind?

 

Thanks for your replies. No, I don't have a plastic coating. I was just reiterating what I had read elsewhere. But now that I think about it, you are right -- powder coating is just a way to coat a pigment, not a plastic. Back to square one.

I think I will do the following
1) Sand whatever 1-2-3 primer I can easily sand away (if it's properly adhered, I won't force it out). I'll continue using a razor blade, but will not overdo it, to avoid unnecessarily peeling off properly adhered powder coat.
2) Sand smooth with 120 grit
3) Liquid deglosser
4) Oil based primer (spray) - ideally grey primer (in case the top black coat peels off down the road, at least the contrast won't be as sharp than if using white primer).
5) Oil based paint (spray), either satin black or gloss black. (Is gloss better than satin so that hinges better withstand friction when opening/closing?)

I will likely use Rustoleum products. Any feedback would be appreciated. Thanks

 

I've never heard of the sheen of paint affecting how well it withstands friction in opening and closing a hinge. I would pick the sheen based on how you want them to look but I do think something toward the higher end of the spectrum would be good, flat does not sound like a good choice.

 

Thanks again.

Regarding primers: would a self-etching primer be ideal? Or the aerosol equivalent of one of those bonding primers like XIM? No matter what, I understand it should be a solvent-based primer, right?

Thanks

 

I don't think there would be a need for an etching type primer. Most if not all aerosol primers/paints are solvent based.

The paint sheen doesn't have anything to do with movement friction, that depends more on the thickness of the coatings.

 

Thanks again for the reply. I went ahead and sanded and deglossed the hinges. To keep all coats black, i decided to use Rustoleum Universal "primer and paint in one / all surfaces" aerosol solvent based. (i decided not to use a separate primer which would have had to be white or grey). I understood (hopefully not mistakenly) that because it's solvent based and because it wasnt raw metal that i didn't need a separate primer. (too late anyway to reverse that).

Final question: i have applied about 4 very thin coats. For the purpose of avoding peeling due to friction of the hinges, is thicker better than thinner? If thicker is better, should i wait the recommended amount of time for paint to cure and then apply a few additional coats? And, should i put some 3 in 1 lubricating oil when installing the hinges to minimize friction and thus peeling?

Thanks

 

From their website:
"
1. What can I paint with Universal™?
Almost anything! You can paint wood, metal, plastic, masonry, concrete, fiberglass, aluminum, glass, plaster, laminate, vinyl – nearly any interior or exterior surface. The advanced formula offers maximum adhesion for demanding substrates and ultimate flexibility for extreme application. Universal eliminates the need for different products for separate projects.

2. Does Universal offer rust protection?
Universal™ offers superior corrosion resistance and rust preventive protection consistent with Rust-Oleum’s popular Stops Rust® paints. "


"5. Do I need a primer when using Universal?
For most painted surfaces, a primer is not required. However, a primer may be needed if the surface is highly porous (e.g., wood) and has not been previously painted."

I am therefore assuming that this product, and they way i applied it, was OK...

 

The paint and the way you applied it should be fine. I wouldn't oil them at this time because the oil might soften the fresh paint. I'd be inclined not to oil them or maybe wait until you expect to open and shut the shutters.

 

Thanks marksr.

To conclude: which one is better when friction is expected -- thinner or thicker total coating? I have a dim recollection that the thicker the coating, the more problems with peeling -- but perhaps that's true in a different context. On the other hand, the thinner the coating, the more likely friction will peel it off exposing the raw base, no?

After applying a total of about 5 thin coats, I can a) leave it as is or b) wait one or two more days, per label instruction, and apply a few more very thin coats. The logic (and I might be completely wrong) is that, if friction leads to peeling, it will be the second set of later coats that might peel away, leaving the first 5 or so coats in place.

Thanks

 

It's the acumaltion of coats or mil thickness that causes the friction. The total is more relevant than each individual coat. With multiple thin coats it's possible that only the top coat would get abraded away but if it's bonded well to the underlying coat........