Question About Paint

Now that we're in 2024, has anyone had any innovations or revelations in the field of painting aluminum campers?

Hi John.

This post is of particular interest to me as I'm planning to paint my trailer once the weather allows later this spring. The painting scares me a bit as I have never sprayed anything larger than garden furniture. I spoke to my local body shop guy and asked how best to prime the bare aluminum and he recommended using an etching primer. I was planning to go that route until reading this post but I am a bit unsure about using epoxy. I was wondering if you or anyone else has any thoughts regarding etching primer vs epoxy primer. The etching primer comes in spray bombs as well and I was also wondering if there is any reason why I shouldn't use the spray bombs for that first coat only.

I am planning on buying a budget spray gun once I figure out what type of paint I'll be using and I saved all of my old damaged siding panels so I have something to practice on before I paint the trailer.

Thanks,

Peter

Peter and Jim,
Thank you for your comments and questions. I will try to answer both together because they are over lapping.

ETCHING PRIMER VS. EPOXY PRIMER
This information was given to me several years ago from an independent paint dealer that supplies the paint to Chip Foose and Disneyland as some of his accounts. Etching primer has been the "go to product" for aluminum primer since before World War 2. Why would we change from anything that has worked for so long? The reason is that the new formulation topcoat paints have changed, and many new topcoats are no longer compatible with the "old school" etching primers. Using a two-part epoxy primer is the new accepted way to prime your steel/aluminum/fiberglass/bondo work. I used epoxy primer under the base coat/clear coat paint job on my 1932 High Boy Roadster twelve years ago, I painted my 1970 Bronco two years ago with an epoxy primer and it sits outside every day. With proper sanding and cleaning preparation I have never had any adhesion or lifting issues, or bleed through. Epoxy Primer works and is the new accepted way to do the job. It is recommended by paint professionals with the highest commercial/industrial paint certifications.

SPRAY BOMBS VS. REAL SPRAY GUNS
It comes down to cost and control. The most expensive way to paint anything is with a spray can. You are paying for propellent, NOT paint material. The only thing good that can be said about a spray can is "convenient". With a real spray gun, you can control anything you want. You can control how fast the paints sets up and dries by the temperature reducer you select for the weather on the day you're painting. You can control air pressure and spray fan pattern. Why is this important you ask. I recently sprayed the inside of a Spartan bathroom. Basically, it's a three-foot square box that you have to stand inside and spray paint. The ceiling has some bead rolls. By using a small spray gun, you can adjust the spray down to a narrow pattern and paint all of the corners and bead rolls first to get good coverage. Wait a few minutes to let the solvents flash off, then adjust the spray back to a normal pattern and put a coat on the walls and ceiling. If you're not happy with how it all blended together, just increase a little extra reducer and spray over the still soft paint and it will all melt together. You do not have the ability to do any of these adjustments with a Spary Bomb.

You need to have a good air system to spray paint. The same air system is needed by any air tools you are using. This is a very large topic we could discuss another time if you are interested.

PRIMER SURFACERS VS. HIGH BUILD PRIMERS
These are different products made for different uses. Let's not mix apples and oranges in our discussion. When we are talking about Etching Primers, or Epoxy Primers we are talking about Surfacers. If you did some body filler work and have some heavy sanding scratches that need to be filled and block sanded, then you need a High Build Primer. Etching or Epoxy Primers are not going to fill anything, they will only seal the surface, which is why they are called Surfacers.

HOW SOON CAN A PRIMER BE TOPCOATED?
That's a good question. It is dependent on the products you are using. It is most important that you select one system and stay with that system from bare metal to final topcoat. Do not mix products, do not mix brands. The solvents used in "old school" primers had to evaporate "through the paint surface as it dried". Depending on the ambient temperature, this could take weeks. If it was forced dried with heat lamps it could/would wrinkle up. In general, it was a PITA and had many chances to cause problems. Today's Epoxy Primers are "chemically cured". Add Part "A" to Part "B" and spray it on a well-prepared surface and it will stick and stay stuck. They dry in hours, not weeks. The most important step is the one we usually only look at after we screw up. Read the MDS Sheet that was supplied with your paint products. The manufacturer took a great deal of time to figure out everything wrong you could possibly do, and they are nice enough to share it with us on the instruction sheets. Even if you "just come close" to their instructions you will have a good result.

Good luck with your projects.

John Palmer

I agree with the advice given above with one obvious caveat…it all depends on how much you can afford.

I did one thread on a $200 paint job using a Harbor Freight gun and oil based paint with an aluminum primer and for the money I think it came out well. I heard from the new owners and 6 years later the paint job still looked good with no problems.

I did a second thread using a PPG (see above) paint and primer with a quality gun. It looked like a nice factory paint job. In my opinion, beautiful. But it sure didn’t cost $200.

You get what you pay for in life.

So the question is, how much can you afford? A cheap paint job that might last 10 years or a quality paint job that might last decades. Both you can be proud of at any campground.

Yeah, I'm with you on prep. When i'm talking to subs on the job I always tell em that this is going to be someone's house for twenty years or their whole life, spend just a little more time and do it right.

I read a quote in my youth that stuck with me for life and shaped how i worked, it went something like this..."When we build, let us build with the thought that we build forever, so that our children will say, 'look, see what our father's built'"