Exterior Renovation (Need help with paint, trim, prep options/products)

We redid the inside of our 1974 Terry Travel Trailer 21' last year and we have very much enjoyed both the process of redoing it and the finished product.  We love a good project and the whole family did it together so it holds fun memories.  Now that the inside is almost completely done (we only have one goucho cushion to recover and 2 sticks of trim to install), we would like to work more on the outside.  We addressed the roof seams with Eterna-Bond 4" tape over seams before we started the inside and made sure there were no active leaks before we got too far on the inside.

I am going to have a lot of questions about redoing the exterior, but first I want to start with the paint job thought process.

*It is aluminum siding and the original paint is either worn off to shiny aluminum or there is barely paint showing and it will come off in a powder film on your fingers, what is the best thing to use on this to clean it and prep it for paint?

*Do we strip it and wet sand?  What will work best on ribbed siding for sanding since it is NOT a flat surface by any means?

*Should I use a special primer for aluminum?  If so what is recommended as a good value with good results.

*About the windows....do I take them all out before painting or should I apply some fresh paintable caulk around them and mask them off to paint?  The putty tape seems a little crumbly under the frames, but I am not looking forward to having to take them all out and reinstall them, but I will if it is the best thing for the overall project.  When I put them back in should I select slightly thicker screws and a bit longer (as long as they don't go through the wall) to hold them more securely since the screw holes will already have been used?

*Where there is flat seam tape on corners etc the previous owners used what appears to be clear silicone caulk on either side of the trim piece (see pic)!  WHY?!!!!!  UGH!  I HATE having to remove silicone, is there a product that actually WORKS to remove it easier?  My husband suggested just putting paintable caulk over the top of it so paint will stick.  I don't know if paintable caulk will stick to the silicone or not.

*I am wanting a white or off white base color and a medium metallic blue in the middle large stripe and a thinner silver or grey strip under that.  The whole inside is a patriotic theme with greyish white walls, deep blue cabinets, and a few red accents so I want to keep with that overall idea, but I don't think I want any red on the outside. 

I have a gravity fed paint sprayer and air compressor for the main color, but I have to be honest I am leaning a little towards rattle can for the accent stripe sections so I can get fancier paint colors and metallic colors without having to buy an expensive quart of automotive paint for each color etc.....is the rattle can a terrible idea?  I have never used a sprayer before (aside from a texture gun for sheetrock and that set up is nothing like painting!)  I want this paint job to freshen up the appearance, it is still a 1974 trailer with some minor dings and imperfections and I can't change that.  I don't want this to cost a fortune, but I am considering buying all new trim for seams for a nice finished look (or I can wire wheel brush the original trim and see how it comes out and install new vinyl trim to cover the deck screws I plan to use to reattach it).  I plan to repaint the visible frame, hitch area, propane tanks, bumper, and step either grey, or black.

What type of paint will work well for the main color?  Can I use exterior house paint that is thinned out?  If so, what type (oil, acrylic, etc)?  Should I use paint like they use for heavy equipment (enamel paint)?  Automotive Paint (this intimidates me because of the additives you have to do to make it work right).  I want the best value, I want the paint to stay on and look nice for quite a while, I want to be able to wash it with a soft cloth or gentle brush, and it needs to be able to handle some road conditions as well.

Bondo and sand the dents smooth. Clean the entire TT with detergent and ScotchBrite pads, let it dry, wipe it off with Acetone, mineral spirits or alcohol, mask off what you don't want painted, then spray it with primer and paint. The scotchbrite pads should rough up the surface enough for the primer to stick, then the paint will stick to the primer. Use your gravity feed for both primer and paint, do the stripes with it too. Rattle can is only good for less than six inches of width.

Our rig is a project, and I am trying to do everything "on the cheap" but not "cheaply done."

I am by far no expert, so this is just what I've learned from my own research. If you are looking for best paint choice, it's automotive, as that's what it's made for. However, automotive paint is super pricey!!! I wouldn't use any paint that is latex based. They won't hold up to the road conditions and weather, etc.  Me, personally I plan on using an oil based paint when I get to that point.  For the accent colors, go to your local big box store and talk to the paint dept. You'd be amazed at what they can come up with. 

The silicone....UGH. Unfortunately, yes, the silicone has to come off. Nothing sticks to it. It's a lot of scraping, pulling and work. It's up to you to re-butyl all the windows or not. I did 2 in our rig, and decided I'm just going to clean up the rest and then caulk around them really well. lol

Prepping the trailer for paint is going to take the longest, and be the biggest pain. I recommend getting this set here;
https://www.harborfreight.com/wire-wheelcup-brush-set-6-pc-60475.html

I wouldn't take out windows..you are going to have to cover holes anyways, right? You're better off using paper/tape. If you want to fix imperfections, Bondo is your friend. Just remember it needs a solid metal surface to stick to.

Make sure whatever you decide to do you use a good primer. That will help your paint stick, and you won't see all your hard work flake away.

Good luck, and keep us posted!! I love what you've done to the inside.  ;D

My opinion is that I would use a flatter sheen paint. You have alot of small dents and dings that unless are filled and sanded perfect will jump out at you with a glossier sheen paint. Keeping your final finish on the lower gloss side would be best to not show imperfections. Similar to a house paint.

Hi,
1. Agree on the silicone - NOTHING sticks to it, including silicone.
2. Certainly do use primer.
3. I've seen some good work done with rattle cans, but I question whether you will save anything.
4. Surface preparation is everything, don't skimp here.

Good luck,

Ernie

Thank you so much for all the suggestions!  I have been walking around the trailer a lot making mental notes on how to deal with every issue I come across.  Silicone will be my main battle!  My dad has a paint bay in his shop that he just finished recently and he offered to help me paint it.  I just have weeks of prep to do first, I don't want to prep and remove the silicone until I am SURE we can afford to paint it and finish it in good time.  I don't want to start it and leave it vulnerable to leakage if I can't finish it. 

So is there a recommended PAINTABLE caulk I can thinly apply around windows and various things like venting on the side of the trailer?  Once I get that silicone off it will need something to transition and reseal it.  When we did our house repainting we feel like the CASES of caulk we used made a huge difference in how it turned out, we are very happy with it.  For dents, damage in the siding I will use bondo and sand, and I will look at my options for a low sheen paint.  So far all I am seeing is oil-based Rustoleum or implement paint as options.  I hear Sher-Cryl is also very good.  It all comes down to a balance between price and quality/durability.  I won't be able to fix every little thing but I do feel like a fresh coat of paint will brighten it up and extend the life.

Another thing I can been considering is that fiberglass rock guard (awning thing) on the front window.  It is pretty weathered and fiberglass fibers are exposed and I don't know how well paint will stick.  There are no cracks or damage to it thankfully.  I thought today that maybe I should look at the underside maybe I can just flip them and there might be a smoother unweathered surface I can paint to match.  Any suggestions on a place to get a fun or even custom decal for the center smooth panel of it?  I thought about getting replacement orginal Terry Travel Trailer decals but I think we'd rather have some fun with it.  On the back we'd like her name on it (we named the trailer Myrtle and refer to her by name often) and maybe "Happy Trails" or "Have a good day!" or something fun.  Any ideas?

As stated above every single dent will show 10x better once it is painted. Fix them and sand them well with the rest of the unit. Think about a single stage paint once ready to paint. Make sure the paint and primer is a chemical marriage meaning same brand is a good idea.

Rattle canning the stripes is a good idea. Do them first, let them cure then mask them when you do the main color. Much easier to make stripes when overspray doesn't matter then mask the small area the stripes take up.