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Senior Space Cadet

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Whenever I spray paint my rocket, I end up with sections that feel rough, like sandpaper. Putting on a really thick coat seems to help, but then I end up with runs.
To fix it, I go over the rocket with super fine steel wool. It's then smooth, but no longer glossy. Putting on a clear coat won't help because it would end up feeling like sandpaper and I'd be right back where I was.
What am I doing wrong and how do I prevent paint that feels like sandpaper?
 

timbucktoo

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What’s the air temp when you’re painting? Too hot and paint can dry before it hits the surface leaving behind a gritty finish.
 

Senior Space Cadet

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What’s the air temp when you’re painting? Too hot and paint can dry before it hits the surface leaving behind a gritty finish.
That's one thing I've been considering. I've done some spray painting early, before it gets hot, but I've done some in late morning and early afternoon, when it's pretty warm. I'll try and restrict my painting to early morning and see if that helps. Late September and we are still getting temperatures in the high eighties. Even hit ninety a couple days ago. Very low humidity too.
 

ATJOE1972

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Whenever I spray paint my rocket, I end up with sections that feel rough, like sandpaper. Putting on a really thick coat seems to help, but then I end up with runs.
To fix it, I go over the rocket with super fine steel wool. It's then smooth, but no longer glossy. Putting on a clear coat won't help because it would end up feeling like sandpaper and I'd be right back where I was.
What am I doing wrong and how do I prevent paint that feels like sandpaper?
Sounds like you might have a distance issue. Too far away from the rocket will cause a gritty finish. Too close will cause it to run. Temperature shouldn’t be an issue, I spray paint stuff from freezing temperatures to the nineties. However the mornings seem to work best with lower temperatures and wind. I would try practice painting on a cardboard box and get a feel for the paint and the finish you’re getting.
 

Nytrunner

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That's one thing I've been considering. I've done some spray painting early, before it gets hot, but I've done some in late morning and early afternoon, when it's pretty warm. I'll try and restrict my painting to early morning and see if that helps. Late September and we are still getting temperatures in the high eighties. Even hit ninety a couple days ago. Very low humidity too.
Read the back of the can. If it lists temperature or humidity rainges to stsy within, obey them. ATJOE's advice about maintaining consistent distance is good also. IE, dont try and hold a rocket on a stick to paint. Set it or hang it somewhere and keep your can distance constant
 

samb

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I agree with ATJOE1972’s distance diagnosis. Too far away gets you dry spray where the paint partially dries before hitting the surface. Even lifting the nozzle at the end of a pass can result in dry spray. Too close and you get sags and runs.
The only solution I know is practice on scraps to get the right speed and distance. It’s really kind of a feel thing. FWIW I’m about 6-8 inches away from the piece I’m painting. I wouldn’t try to fix a dry spray coat with more paint. I’d wait and sand the gritty surface smooth.
 

Nathan

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ATJOE is probably right. Getting the perfect paint job with a spray can requires keeping the can at the right distance and keeping it moving at the right speed. I get the best results by spraying as heavy a coat as possible without causing runs or sags. First coats can be lighter but final coat needs to be heavier.

You can also get the rough coat problem you described if the paint needs to be thinned but that's not an option with a spray can.

Attached is a picture of my Loc Onyx that was painted with Duplicolor Perfect Match Lacquer from a spray can.
 

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dr wogz

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All mentioned my initial thoughts..

I will add that distance & speed are key. I can see people spraying their object, but rotating their body at their hips, therefore spraining an arc: Too far-just right-too close-just right-too far.. Star the spray before the object, and end the spray after the object, as you move thru the motion

Also: long, smooth, even strokes. I see people "colour" with a can.. Colouring like you do with markers or pencil crayons to fill an area. half-hazardly shaking your hand as you paint to try & cover as much area as possible in one stroke. No! Long smooth even strokes. Rotate the object for the next pass, Repeat..
 

OverTheTop

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Someone posted a video recently of a guy using rattle cans on car panels. Results were amazing. I can't seem to locate it.
 

SCooke123

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Yea I think mainly distance from your rocket and the speed you are moving the spraycan are your culprits! Practice helps a lot - the more you spray the better you will get.
If you do get a sandpaper type finish, sandpaper is your friend - just smooth out the finish and apply the next coat.

Also don't get discouraged! Even seasoned painters get a screw-up every now and then!
 

Senior Space Cadet

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ATJOE is probably right. Getting the perfect paint job with a spray can requires keeping the can at the right distance and keeping it moving at the right speed. I get the best results by spraying as heavy a coat as possible without causing runs or sags. First coats can be lighter but final coat needs to be heavier.

You can also get the rough coat problem you described if the paint needs to be thinned but that's not an option with a spray can.

Attached is a picture of my Loc Onyx that was painted with Duplicolor Perfect Match Lacquer from a spray can.
Holy crap! Mine definitely don't look like that. My truck's paint doesn't even look that good.
 

Senior Space Cadet

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Read the back of the can. If it lists temperature or humidity rainges to stsy within, obey them. ATJOE's advice about maintaining consistent distance is good also. IE, dont try and hold a rocket on a stick to paint. Set it or hang it somewhere and keep your can distance constant
You mean I'm not the only one that paints their rocket by putting it on a stick and holding it with one hand while spraying with the other?
OK, I'll come up with a better rig.
 

jrap330

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ATJOE is probably right. Getting the perfect paint job with a spray can requires keeping the can at the right distance and keeping it moving at the right speed. I get the best results by spraying as heavy a coat as possible without causing runs or sags. First coats can be lighter but final coat needs to be heavier.

You can also get the rough coat problem you described if the paint needs to be thinned but that's not an option with a spray can.

Attached is a picture of my Loc Onyx that was painted with Duplicolor Perfect Match Lacquer from a spray can.
That red paint Job has to be an air sprayer.......if not...Wow.
 

dr wogz

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I've done a few on a stick, stick in one hand, can in the other. But I do pay attention to speed & distance.. It does take practice! And, some paints are easier to work with than others..

I typically will clamp said stick (or broom handle for HPR!) to the end of my pic-nik table, and then spray that. Spray-rotate-spray-rotate-spray-rotate-spray-rotate...

oh, and about every 5th or 7th pass, I'll give the can a bit of a shake & spray (away from the object) & wipe the nozzle.

oh, and do keep the can vertical. some try to paint by eventually turning the can completely upside down to get "into" an area.. (It starts out vertical: nozzle on top, and eventually they are painting with e can at a 45° angle. Rotate the object, not the can!

Another note is the nozzle itself. The spray pattern can be changed on some cans, from a vertical spray "oval" pattern to a horizontal pattern (Krylon cans if I recall). Knowing this can make a @#$%^& can of paint become the god-sent can of paint!! And, some will sell different nozzles for either fine line work or massive paint dumps for large area fill (high end 'grafiti' paints)..
 

nelie61

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Everyone has forgotten to mention a very important thing about rattle cans.... Shake the living daylights out of them before starting. Most instructions say 1 min. but a good couple mins. don't hurt. Also Lacquers turn out and spray a lot nicer than Enamels but are more expensive.
 

Nathan

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Everyone has forgotten to mention a very important thing about rattle cans.... Shake the living daylights out of them before starting. Most instructions say 1 min. but a good couple mins. don't hurt. Also Lacquers turn out and spray a lot nicer than Enamels but are more expensive.
I never use enamel anymore. You can get just as good a paint job with enamel but lacquer is fully dry as soon as the solvents evaporate while enamel has to cure which takes a while. Enamel can take a couple of weeks to fully cure. Lacquer is harder to find; most rattlecan spray paint is enamel. For rattlecan lacquer I recommend Duplicolor which is available at most auto supply stores.
 

Nathan

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That red paint Job has to be an air sprayer.......if not...Wow.
That was all rattlecan lacquer. But it had several coats of clear lacquer and was wet sanded and polished.
 

Zman1961

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In my experieince the Duplicolor/automotive rattle cans (lacquer) provide a much higher quality finish than the rattle can enamels like Rustoleum and Krylon, but are of course more expensive. Think "several thin coats" instead of one thick coat. The clearcoat with the automotive paint also helps get that nice gloss. After the lacquer dries for a few days I also find that polishing/buffing (light pressure) with a clean, dry, piece of polarfleece material helps too.
 

Jim Hinton

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One thing that has really helped my work is to properly support the work piece. If you are trying to paint with the work in one hand and the sprayer/can in the other, it will be difficult to set and maintain a proper distance for spraying. You definitely want to use a stick or wand to hold the rocket. My best ones have been made by epoxying a dowel rod into an expended SU motor casing. 1/2" dowel, a couple of feet long works great. I have an old kitty litter jug that I have filled with sand. You can insert your dowel into the sand, it will support up to most L2 rockets. Overspray all over the jug doesn't cause heartburn. With the rocket safely supported for hands free work, it's a whole lot easier to control the paint application.

Jim
 

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The lacquer tip sounds like a winner. I'll look for the Montana brand. There are a couple craft stores around here that might carry it, otherwise I'll order it.
Thanks guys. I think this puts me on the right track. If my next rocket looks bad, I have no excuse.
 

Banzai88

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The lacquer tip sounds like a winner. I'll look for the Montana brand. There are a couple craft stores around here that might carry it, otherwise I'll order it.
Thanks guys. I think this puts me on the right track. If my next rocket looks bad, I have no excuse.
Typically it's higher end art stores for Montana. Dick Blick or Jerry's Artorama. Either way, you're going to like it! Just a quick tip, though, it sprays like nothing else you've ever used. Most of us get a little closer and spray a little thicker than you're probably used to when using it. For certain spray a test piece a time or two to get the feel for it. You can also spend $7 and get the pack of different spray heads for the cans, too! If you get a finish that's too rough it cuts nicely with wet 1000 grit and polishes up nicely.....or just top coat it with Max 2K clear (which is a 2 part mix-in-the-rattle can automotive type clear that's AMAZING. Check out the youtube videos on it).
 

PayLoad

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Don't over-think it - shake can for twice the recommended time & watch the distance from what you are spraying. Rough finish means you are too far away, simple as that.
 

Philip Tiberius D.

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In my experieince the Duplicolor/automotive rattle cans (lacquer) provide a much higher quality finish than the rattle can enamels like Rustoleum and Krylon, but are of course more expensive. Think "several thin coats" instead of one thick coat. The clearcoat with the automotive paint also helps get that nice gloss. After the lacquer dries for a few days I also find that polishing/buffing (light pressure) with a clean, dry, piece of polarfleece material helps too.
Tamiya and Testors both make killer Lacquer paint which I have used and put down some great finishes for me (but $$). DupliColor is another great Lacquer I’ve had luck with.
 

Banzai88

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The flip side of lacquer that no one has mentioned yet is that it's significantly less durable than enamels by itself. That's why I top coat with 2K, which has that durability and can be repeatedly polished like a car, if necessary.
 
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