"Serge F. Vidal" wrote > 1) Surface preparation > - To which grit should I sand the surfaces? Is 600 grit, dry sanding OK?
I'm no expert, but I guess one amateur opinion is better than absolutely nothing. If you're going to apply the paint directly to the old paint, 400 is probably best. Dry or wet is OK, but wet sanding will make the paper last longer, although it's more messy. If the paint is really ancient and you have no idea what it is, you should probably seal it first with sealer (or test it first) to make sure the paint is compatible with what you're going to put on it (although it may take years to screw up). > - There are a few areas of the skin that are slightly cracked. For example, > I have thin cracks around the elevator hinges. Should I resurface these? If > yes, is Polyester body filler OK? I think if you paint over them or use body filler over them they'll just come back. Patching with fiberglass is the right way to do it, but that may be more trouble than you're up for. Your choice there. > 2) Choosing the paint > I am given a choice between polyurethane/polyester and polyurethane / > acrylic. Which one is best? I didn't even realize that there were two kinds of polyurethane until now, but I can tell you that I painted mine with the cheap stuff, and it's polyester based. The expensive DuPont that I bought to match my wife's Audi is acrylic. I figure since my plane is going to spend the vast majority of it's time in a hangar, and since the UV protection is really in the clearcoat anyway, that'll work just fine for me. Ask at your paint store, but for me the answer was that the good stuff was $130 a quart, and the cheap stuff (which looks just great) was $30 a quart. It took a gallon of paint (which is 1.5 gallons of sprayable stuff after adding the activator/reducer) to paint my Scirocco with three coats (which is what it took to cover the old paint and primer patches here and there). Obviously, the best place to get paint advice is where you buy the stuff, but here's what I learned from them. The cheap stuff doesn't cover quite as well, so if you need 2 coats of DuPont, you might need three coats of Nason. And the matching to OEM colors is better with DuPont than with Nason, but one gallon of Nason will match another one perfectly. They told me that most pros use the expensive stuff for repairs (where matching is critical) and Nason for a total repaint. In my automotive paint class the rules were sand with 180 before priming, and then sand the primer with 400 before painting, and then touch up the color with 600 between coats, and 1200 if you have a problem before clearcoat. Like I said though, I ain't no expert... Mark Langford, Huntsville, Alabama N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford
