Painting in cold weather

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4regt4

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I've heard it's not good to paint in cold weather, but this winter I've painted 4 rockets outside in 45 deg temps. They turned out great (with one caveat, see below).

I realize rattle can painting is all about technique, and I basically have none that work well. I struggle greatly in the summer, with paint either 1) going on very rough, like sandpaper, or 2) with considerable orange peel, or 3) runs and sags. The sandpaper texture appears to be paint drying as it hits the surface and not blending in. The other 2 faults are probably from too much paint. But if I don't use too much paint, it goes on like sandpaper. Arghh....

So with some naked rockets laying around waiting for a decent day, I gave up and just painted anyway. I've gotten in the habit of placing the cans in a sous vide bath at 90 degF, as they seem to mix better. Then outside they go, spraying in mid 40's temps. I get a great glossy finish with just one coat. The paint seems to dry much slower, so any sandpaper like texture that may be initially apparent just melts into the surface after a while. I don't apply super thick, and just rotate the rocket for a couple of minutes before standing upright to dry. Which takes a while...... After a few hours, the fumes are usually still quite strong, so I move it to the garage overnight. Anyway, I've had no rough finish, no orange peel, no runs or sags. I've used Duplicolor Gloss Black, Gloss White, and Gloss Red, Rustoleum 2X Orange, and regular Rustoleum Yellow. They have all worked well.

The one caveat: On very humid days, like slight fog, I get some "bloom" on the gloss black. This is a foggy appearance that looks like when you fog a mirror. At least that's what we called when I used to work around an auto body shop. But no worry. After it dries for a few days, I just polish with Meguiar's 105, then with 205. Nice and shiny. Only takes a total of 5 minutes to polish out a 3" diameter nose cone, if that. I just use paper towels to polish with.

So now it looks like I fly naked in the summer, and do my finish work in the winter.

Hans.
 
I also warm the can in hot water, and have had success painting in temperatures as low as 35 degrees Fahrenheit. I keep the rocket inside the house before painting, so it's temperature is about 70 degrees Fahrenheit. I assume you are doing the same?
Yes, close. My house is kept at 60 deg, but the rockets are inside.

A quick pic of the black end of a 3" body tube: (This one was painted on a dry 42 degF day, and didn't get the "bloom")PaintFinish.jpg
 
I have no patience to wait for the next season to come! With everything warm and ready (sometimes move the cars out of the garage), I take the rocket in the garage, spray one coat, then move the rocket inside (usually to the basement) to dry. The rocket is only in the cold for ~ 3 minutes top. I can get decent coverage before too many runs! :p This is all rattle cans of course. Usually Rustoleum paint and primer. Good luck!
 
I have no patience to wait for the next season to come! With everything warm and ready (sometimes move the cars out of the garage), I take the rocket in the garage, spray one coat, then move the rocket inside (usually to the basement) to dry. The rocket is only in the cold for ~ 3 minutes top. I can get decent coverage before too many runs! :p This is all rattle cans of course. Usually Rustoleum paint and primer. Good luck!
But what I'm kind of saying is that I get much better results spraying in the cold. If I used your method, I'd still be fighting the same issues that I have in the summer.

Hans.
 
I don't typically paint below freezing even if I can find an indoor space. I've used my buddies empty garage in a pinch but I don't care to do that if I can avoid it. Like you I warm the paint for about 20 mins before spraying. I also shake it about every 5 mins then set it back in the warm water. As for the rocket, I warm the rocket with a heat gun just prior to spraying. I also like to warm it from the inside so it's not just the surface that is warm. This is the last step before I shoot so the rocket is warm to the touch when I go outside.

If I have the luxury of spraying inside, I'll take my head gun with me and warm the rocket between coats. I've found that primer can be sprayed pretty much at time but paint gets really unhappy below freezing.
 
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