Painting in Cold Weather

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lcorinth

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User dpower mentioned that he sometimes paints rockets in cold weather on one of my threads. I'm really tempted to try this, because I've got three rockets to paint. I'd like to finish at least one of them by next week's launch.

But I wanted to get some feedback from other users as well. Anybody else tried this? How did it go? I'm thinking of using his technique, warming the can, running everything outside for a coat, and bringing it back in to dry (currently using enamel paint, which he said can be trickier than lacquer).

I have designed an indoor painting booth, but have yet to build it, or find a place to set it up (though I've got a lead on that).

Thoughts?
 
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Lacquer is no problem in the cold, in fact it works better in the cold due to reduced risk of blush/milking. I've done it many times and still do for clear coats. I use acrylic airbrush paints inside for color coats now so outside weather isn't an issue.

When I used to paint with enamels, I didn't have major issues with "cool" (40s-50s) except that the drying time expands from a day or two to a couple weeks before you move to next step.

Marc
 
Lacquer is no problem in the cold, in fact it works better in the cold due to reduced risk of blush/milking. I've done it many times and still do for clear coats. I use acrylic airbrush paints inside for color coats now so outside weather isn't an issue.

When I used to paint with enamels, I didn't have major issues with "cool" (40s-50s) except that the drying time expands from a day or two to a couple weeks before you move to next step.

Marc

Actually, I'm curious about airbrushing. Do you need to prime it first? Is there a special primer for airbrushing, or do you use the standard sandable primer you'd use if you were painting with rattle cans? I'd like to paint indoors, and an airbrush sounds like a good option, but I know very little about it.
 
Actually, I'm curious about airbrushing. Do you need to prime it first? Is there a special primer for airbrushing, or do you use the standard sandable primer you'd use if you were painting with rattle cans? I'd like to paint indoors, and an airbrush sounds like a good option, but I know very little about it.

Keep in mind I'm only LPR and low-end MPR, so relatively small birds compared to what some people do. I don't have anything bigger than BT80.

I prep my rockets the same as if I was going to be using lacquer or enamel. I usually use Rustoleum filler primer, sand that down, then instead of using a white rattle can primer (or in some cases a dark rattlecan primer), I switch to the airbrush.

I prime with Createx Auto Air Sealer White (or Sealer Dark for dark colors) on top of the sanded rusto filler primer. Most of the time I use a mini spraygun (<$15 at Harbor Freight) to apply the sealer primer.

Then I use either the mini spraygun or a smaller airbrush to put on the color coat. Often, I'll use the spraygun to put on a coat of opaque white (Auto Air or Wicked Colors, typically), then apply the color on top of that. It goes quickly, and can be done in my basement, though I recommend a respirator to prevent getting the paint in the lungs. Just because it is mostly aqueous with only a little volatile solvent, doesn't mean it's not bad for the lungs.

But the stuff doesn't stink, the wife doesn't complain, it dries quickly (light coats!!), and I can clear coat it with lacquer, enamel, Future, or high-gloss varnish.

I recommend acrylics highly!
 
Well, guys, I did it, and it seems to have worked great! The white undercoat is drying now, and everything looks pretty good.

Here's what I did:

I got my little painting table all set up outside, then mounted the rocket to my painting jig, ready to go just by the back door.

I boiled some water and poured it into a tall 2 liter pitcher, then added hot tap water to that (I wanted hotter water than I get from the tap, but not boiling hot). I put the can in the water for about five minutes.

Once the paint was warm, I grabbed the can and shook for one minute - it was pretty warm! Almost, but not quite, uncomfortable to hold.

Then I ran everything outside, did a light first coat, and brought everything back in. I wanted to be extra careful with light coats, so it took one more coat than it normally takes me (I usually get everything in about 3 coats, this one took 4). But we're looking smooth and clear. Pics to follow when the topcoat and decals are done.

(Oh, this is a Quest Quad Runner - a 4-motor cluster rocket. Biggest one I've built yet, I think, or pretty near it.)
 
I did some painting in 40 Degree weather today. I did it at around noon, then let it stay outside til' about 3:00pm.
I went out and put a plastic bag around it before bringing it in so that my House does not begin to smell of it as it continues "Off-gassing".
Hung it up in my laundry room where it is around 65 degrees, still in the bag. Maybe f it is nice outside tomorrow, I'll take it back out and take the bag off to let it breathe, then see if it still stinks before deciding whether or not to bag it before bringing it back in.
The Rusto High Build Primer goes on nice and thick in the cold, and I like that.
I did warm the Can in hot water first, and shook it thoroughly.
I hate the Smell of Paint, and even though I paint outdoors, I where my 3M Respirator and a Face Shield to keep mist from finding the lenses of my glasses or accumulating on my Face. Nitrile Gloves too, as I don't want Chemicals on my Hands. Safety First!

M104Primer 003.jpg

M104Primer 004.jpg
 
I've been painting in cold weather for years. I use the warm the can method,along with "spray+dash"(spray a coat and dash back inside).
I don't mind the smell of paint, so I let it dry in the corner of the kitchen.
I have had good luck doing this using Rusto paints and primers, beware it's EASY to get runs,so many light coats are a must.
 
Yes, lol, I am a "Spray and Dasher" also. Nothing to big, and usually only primer coats. Rustoleum is my current paint of choice, and yes I have noticed light coats are the best. I feel lucky to have a large furnace room for quick drying. Last month my "Assistant in Charge of Low Power Operations" drew up 5 plans for our winter build pile. Guess who has a builders kit under the tree, and other parts to make it happen? One happens to be a 8 motor cluster (7x18mm + 1-24mm). I have even wrapped some B6-4 multi-packs and get to call them gifts! Lets hope we have some warmer weather every so often this winter!
 
Well, guys, I did it, and it seems to have worked great! The white undercoat is drying now, and everything looks pretty good.

Here's what I did:

I got my little painting table all set up outside, then mounted the rocket to my painting jig, ready to go just by the back door.

I boiled some water and poured it into a tall 2 liter pitcher, then added hot tap water to that (I wanted hotter water than I get from the tap, but not boiling hot). I put the can in the water for about five minutes.

Once the paint was warm, I grabbed the can and shook for one minute - it was pretty warm! Almost, but not quite, uncomfortable to hold.

Then I ran everything outside, did a light first coat, and brought everything back in. I wanted to be extra careful with light coats, so it took one more coat than it normally takes me (I usually get everything in about 3 coats, this one took 4). But we're looking smooth and clear. Pics to follow when the topcoat and decals are done.

(Oh, this is a Quest Quad Runner - a 4-motor cluster rocket. Biggest one I've built yet, I think, or pretty near it.)

I would caution against getting the can TOO hot! Warm is good, but if the can gets too hot, it can over-pressurize it. I've heated a can before and then while shaking it, there was odd pop noise, and the concave bottom of the can popped outward as if there was a small explosion inside the can! It bent out so far that the can would not stand upright after that! If the bottom had blown out and got paint all over the patio, I would have had to move out and find a new home very far away, never to return to my former life. So make it warm, but not too hot, and don't shake too hard.
 
I've never had the need to heat up the can at all. It will take awhile outside before the can starts to get too cold. The biggest problem I've had is when it's really cold and the atomized paint wants to freeze in the air prior to hitting the surface of the rocket. I try to find a place outside where I can be shielded from the wind. Sometimes that's the front porch. Keeping the cold air from blowing the paint mist away really helps.
 
I always warm the can with a soak in just above room temperature water.

The technical explanation I have heard is that this increase in temperature helps atomize the spray droplets for a finer coating.

I don't know if this theory holds water or not.
View attachment 249563
 
I wonder if putting a "Can Coozy" on a Spray Can would keep it warm longer or be of any benefit whatsoever.
Perhaps a Can Coozy with a Hand Warmer Packet tucked inside, but with some tissue between the two so it does'nt get too hot?
 
I hate the Smell of Paint, and even though I paint outdoors, I where my 3M Respirator and a Face Shield to keep mist from finding the lenses of my glasses or accumulating on my Face. Nitrile Gloves too, as I don't want Chemicals on my Hands. Safety First!

Gee, what kind of respirator do you use? I hate the smell of paint, too!
 
Gee, what kind of respirator do you use? I hate the smell of paint, too!

This 3M I got at Ace Hardware. This is actually the second one I've owned, as the straps wore out on the first one(Lasted about 10 years). The Cartridges are replaceable.

My 3M Respirator 002.jpg
 
Thanks! Looks like I'll be going to my local Ace ... as soon as all the holiday shopping madness is over.

Merry Christmas, to everyone, btw!
 
Basicly all thats needed is to have the model to be painted surface and the Spray Paint can at or above 65°f for best results. Soaking the can in Hot Tap water for up to 4 minutes is perfectly fine. If your model is in a cool garage warming the model indoors or using a Hand Hair Drier to bring the surface temp up works well.
As old dude mentioned Soaking the Rattle can in Hot tap water increases the internal pressure while warming the paint contents giving a finer atomization which allow the spray to reach the model before drying.
Once the model is painted Marc G's "Spray and Dash" method is the perfect solution to outdoor cold weather rattle can or Airbrush painting.

Warming the airbrush bottle containing the paint is done the same as for Rattle cans but you can leave the bottle in the hot tap water for as long as you like however a minimum of 3 minutes seems to work best for me when the Outdoor temperature is 40°f and below.

Have to say though; Putting a ducted spray booth in the basements vented to the outside sure takes all the fight and smell out of Winter cold weather painting;) I've had two in my Model Shop dungeon for more the 30 years, the better 2/3rds and kids never complained a bit:)
Actually the only time we (whole family) ever smelled anything I've rattle can painted in the basements during the winter was a large Z-Gauge Train cabinet in Old formula Krylon Gloss Black...Now that stuff Stinks LOL!
 
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It gets a bit chilly here in Minnesota, so we do the spray and dash too. But I have never heated up a can, I just keep it at room temperature. Take it outside, spray, and bring it back in.
 
Yesterday, with outside temp a cool 15F (and no humidity to speak of :grin: ) I clear-coated my EPM-101 plus an extra nose cone I needed to make red (color coat accomplished previously, inside, using airbrush acrylics). Using Valspar clear lacquer: The rockets were warm (room temp) and the spray paint was warmed in hot water. I got that rarity of rarities: a single coat clear lacquer finish. Under normal conditions I mist on several coats getting progressively heavier. But when it is super cold out, you can spray a single medium coat and the paint just flows together. No runs or drips (holding the rocket horizontal during spraying), and the "overspray" as I went from section to section just blended beautifully with what had been sprayed previously. No need for a second coat.

Marc
 
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