I have some plastic parts I’d like to paint (enclosures for electronics i sell). A nice silver color would suit them. But try as I might, I can’t get acceptable results from spray paint.
I can’t get a completely even coat (there’ll always be a splotch that’s more silvery than another), and I can’t get good durability (in particular, resistance to scratching). I’ve tried a clear coat, but that doesn’t seem to help against scratches and even seems to make the silver look dirty and more splotched.
Am I doing something wrong? Is there a big secret of spray painting that I’m missing? Or is, duh, spray paint the totally wrong way to go?
But, say, I can afford to get these professionally done (using “real” technology, whatever that might be). Is this possible? Will it give satisfactory results? Who would I go to? Not a body shop, surely… Or a house painter…
For durability you need some type of self etching primer. Be careful sanding any plastic parts cause the scratches will show through. It’s been a long time since I have painted a car but if memory serves me correctly silver was hard to paint and you had to drop the gun pressure to allow for even coverage. You can’t do that with a spray bomb so you might try very light even coats sprayed at a little more distance than you are currently using.
Yeah, that does give great results. I can use this for one piece (the front panel) that are made to order. But the main body is an off-the-shelf enclosure that only comes in black (i believe) ABS.
Does this come in a metalic, or at least gray, color? What is the scratch-resistance? The Rust-O-Leum Painter’s Touch (which is the brand stocked by Home Depot) Metallic Aluminum can’t stand so much as a fingernail.
I think the problem may be the metallic color itself. Other colors are easier to paint and are tougher, but this metallic paint changes its character depending on the microscopic details of its surface. Areas of differing thickness and the slightest scratches show through.
Yup, apparently silver is hard to paint. Backing up on the distance is logical, except that the paint’s glue somehow evaporates and basically it does not deposit correctly. I would love to be able to go to someone with pro spray equipment, but I worry that they wouldn’t know what to do with a plastic part. (Eg, a body shop would only know how to paint cars. A house painter, wood and aluminum siding, etc.) I would also be willing to invest in the equipment myself, if I knew it’d give the right results, was clear on which paint/clear coat to use, and everything would be within a few hundred dollars’ budget.
Have you tried the dye they use for automotive interiors? That seems to be very durable, and sticks to plastic well, although I’m not sure you would get the finish you want. Here’s a can for sale on eBay:
But I’m sure it’s also available at a local auto parts store. I’ve used it before to freshen up a worn interior, and it worked well on the hard plastic pieces as well as the areas listed in the ad.
Have you considered something like this which is a “paintless tape”? A local plastics company makes that stuff, always reading about it in the newspaper (as press releases, not testimonials or anything!)
Most likely a local sign shop will have a paint booth Note: a company that makes real signs, not graphics and banners, although those companies could certainly point you to one in your area…that’s who they’re gonna sub their larger and custom work to. Mid-size sign fabricators are almost always generalists, and work with a variety of materials, of all sizes, shapes and specifications.
I know of at least one company in my area (Madison, WI) that would take on any job like that no problem, and you’d probably pay more for shipping than the work, in job lots.
You might try baking the pieces to see if that will make the finish cure harder. High temperatures are out because of the plastics of course, but you might try some of your previous tests that are already marred at progressively higher temperatures until they begin to deform. Then back off a bit and bake for a half hour or so.
NOTE: Make sure the pieces are completely air dry first due to volatiles in the paint.
Thanks for the tip about sign shops. They’re exactly the generalists I was looking for. I’ll try to get a hold of some.
I’ve ordered the automotive stuff, and I’ll try getting a hand on krylon. The trick with baking is clever (seeing as I don’t have much patience). I also need a good clearcoat. The Rust-O-Leum clearcoat is just the worst (ruining the color and having no durability). If I had a good clearcoat, I think that would solve 75% of my problems.
About airbrushes… I see there’s kits on ebay for $100 - $200. That’s within my price range and I could probably get the hang of using one (esp now that I have had practice with spraypaint). But what kind of paint would I use with them?
I don’t think that an airbrush is the answer, they are designed more for fine detail work and I think you will have a harder time trying to get even coverage
Get some latex rubber gloves. The natural oils in your skin can cause the paint to not adhere properly.
Clean the part you want to paint with a “ScotchBrite” pad, then, clean it again. If you think it’s clean, clean it again. The pad will remove some of the shine and will leave some very light scratches for the paint to cling to.
Get a Plastic Primer/ Adhesion promoter similar to something like this:
You should be able to get this at an automotive shop that sells paint, Something like NAPA here in Canada.
Follow the instructions on the can, prime, then prep for paint.
While at the paint selling shop, pick out the color you want, most of these places can put it in a spraycan for you. I would suggest getting it in a lacquer, It driess quicker and you can sand out any runs if need be. You can also pick up a spraycan of clear lacquer.
This should do the trick and get you on your way to a perfect paintjob. Preperation is the key to getting the paint to stick. Patience is the key to getting the paint to look good. Do not try to get the paint to cover on the first coat, it may take three coats to completely cover the part, maybe more to get the desired finish.