does acrylic over enamel

[robertbruce]

does acrylic over enamel work? or will it just fall of?...

i have a 4x4 bus, it gets scratched and I am looking at my options for painting...

it already has 4 coats of paint on it including thinned-out solarguard brushed on some panels. Painting it half-properly would involve setting up a compressor driven paint shop in the driveway, rigging some sort of dust screen/canopy/tent to the bus and dropsheeting the floor to protect the lovely pavers - did i mention i live on the first floor, have no downstairs storage and have set-up and pack-up after each work session...

would shaker-cans make better solution for my current circumstances?

Im thinking an early morning start and guerrilla attack it one side at a time with a random orbital sander and a dozen shaker-cans...im hoping enamel works over enamel

[69SCJ]

If it is oil base enamel I think you need to use the same thing or you will have problems. Do a liitle digging online to make sure I'm not not giving bad advice.
Tyler

[robertbruce]

i did some searching, bit of a nightmare really... i might be able to seal it enough to last a little while with some tricky undercoat...

there isnt a quick way, the equations of the options seem to add up to the same, as usual...

[White Knight]

Acrylic lacquer over anything tends to lift the finish under it, unless the paint is really old and aged, urethane or really tough like epoxy's. Lift means, wrinkling or crazing, or reacting to the topcoat that has been applied.

The thing to remember with all finishes is if they are hardened with catalyst you can usually apply anything over them. Enamel over enamel is fine, IF it is really old, aged and cured hard.

After applying POR 15, an etch primer should be applied to all bare metal. Then followed with a high build primer ( if you have flaws that need filling), or primer surfacer, preferably one that is catalized. BTW: POR 15 offers great tech support as I called them and they were great.

Acrylic lacquer was a great product in it's day, but got too hard, and tended to crack/craze when old and aged, and would crack over time when applied to heavy.

[72BahamaBlue]

I like to let the sanded panel air out for a day or two. I sanded original paint, sprayed some Rustoleum enamel primer right after sanding, paint lifted.
Waiting a day or after sanding helped.

[Norton]

does acrylic over enamel work? or will it just fall of?...

i have a 4x4 bus, it gets scratched and I am looking at my options for painting...

it already has 4 coats of paint on it including thinned-out solarguard brushed on some panels. Painting it half-properly would involve setting up a compressor driven paint shop in the driveway, rigging some sort of dust screen/canopy/tent to the bus and dropsheeting the floor to protect the lovely pavers - did i mention i live on the first floor, have no downstairs storage and have set-up and pack-up after each work session...

would shaker-cans make better solution for my current circumstances?

Im thinking an early morning start and guerrilla attack it one side at a time with a random orbital sander and a dozen shaker-cans...im hoping enamel works over enamel

I don't know how good of a finish you are hoping for, but if your has already been painted 4 times and one of those was a brush job, you're going to need to sand all of that off. (I don't know what solarguard is, but it sounds like something you put on the roof of mobile homes.) Acrylic is just a type of resin, if memory serves me. There is Acrylic Lacquer, Acrylic Enamel, Acrylic Urethane... You can put just about anything over a catalyzed product. Lacquer utilizes a very strong solvent (thinner) which will penetrate and lift a non-catalyzed finish. Lacquer was a great paint in its day, and still is really. It just takes a lot more work and is not nearly as durable as today's coatings. Still, nothing achieves the depth and luster that can be had with a properly applied and cared for lacquer job.

If I were you this is what I would do in your situation and location: Get you a good DA (dual action) or random orbital sander. You're going to need to sand off as much of those four coats as possible and definitely all of that solarguard, unless you just don't car what your bus looks like. Any bare metal is going to need to be treated with a zinc-chromate or comparable sealer-primer. Because you have so many coats of paint and unless you sand the entire vehicle down to the last (or should I say first) coat of paint, you are going to have a somewhat wavy surface when you are done, even if all your sheet metal is straight. Depending on how fine of a finish you want, you may want to apply a filling primer at this point. Otherwise, I'd shoot a coat of non-sanding sealer, let it dry and paint. I used to cheat a lot by using non-sanding sealer. There used to be a product called Jet-Seal that was a non-sanding sealer, you could apply it over bare metal, it would fill 180-220 DA marks, and you could shoot virtually any topcoat over it except lacquer. I say any topcoat but I actually always used acrylic enamel with a hardener (catalyst). It was a real timesaver and I always got good results.

I've been away from PBE for over 20 years now. It was always a quickly changing industry so I have know idea what is out there now. I do know that they are making some amazing spray can products and the spray valves have become pretty sophisticated so that you can actually get a decent spray pattern. You'll never get anything approaching a professional finish with rattle cans, but with care and patience, you could be pretty pleased with the results if you want to go that route. Of course, you can't get any kind of catalyzed finish from a spray can.