Best method to get a smooth paint job?

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Rktman

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Suggestions on the best way to smooth out the "orange peel" you're left with after painting with a rattle can spray paint?


Before you say "better technique", let me say that I always keep the recommended distance from the model while spraying, use an even stroke starting both before and ending after the model, never try to overload it by trying to lay on all the paint in one pass, tried warming the can in hot water first to atomize the paint better, and clean the nozzle both during and after with thinner. Same result.


I've tried several different brands and sizes but they all seem to emit globby droplets instead of a really fine mist. So is it impossible to end up with a mirror smooth finish using an aerosol paint can? And how do you deal with removing the rough "orange peel" finish that you're left with? (I've tried using super fine grit sandpaper, baking soda, car polishing compound and even toothpaste to smooth it out but they all dull the finish).
 

Zeus-cat

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watch the temperature and humidity when you are spraying. You might be out of the recommended ranges. Otherwise, your technique is better than mine.
 

GDJ

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watch the temperature and humidity when you are spraying. You might be out of the recommended ranges. Otherwise, your technique is better than mine.
Agreed.

Also keep in mind that spray can paint isn't what I would consider "top notch" paint. There might be inconsistencies in the batches, issues with primer/paint compatibility, and so on and so on.
The manufacturers put alot of thinner in the paint for fast drying, but sometimes that's not the best route.

The only paint I've ever used that almost never gave me orange peel was Rustoleum Epoxy Appliance paint. Tough as hell, but it takes forever for it to dry (sometimes I had to wait a week until I had to handle it) and the colour selection is pretty limited (black, white, grey, sometimes red if your stars and moon is in alignment) but it works well. As for primer, Rustoleum self etching primer works very well with plastics.

I do wish you the best of luck in finding a method/paint that works well for you. Don't forget to shake the living hell out of the cans. ;)
 

tomsteve

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light mist coat first, then medium/wet coats. if, when i get OP( on a rocket), i make a decision- am i ok with it? if yes, leave it alone. if no, sand with 800 grit and add another coat or paint. or if i didnt break through the paint, add a few coats of clear.
if ya want to sand and buff, we're going to have to know more- what grit did you use to sand with( super fine could be anywhere from 400 to 4000 grit),what compound used, and what method for buffing.
toothpaste is for brushing teeth and baking soda for keeping the fridge smelling good. :)

atomization is a good thing, but i can get OP even if im using my devilbiss copper tekna if im not laying down enough product.
 

Screaminhelo

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My best finishes seem to happen when I get the wet coat right in the verge of running and have to turn the rocket for a bit to prevent. When it is practical, I like to spray a base coat of the finish color (complete coverage but not too thick), sand that with 300-400 grit to even things out, and then do the finish coat.

I have managed some very smooth color coats using the above approach, but as others have posted, sometimes the final coat orange peels any way.
 

ThirstyBarbarian

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If the paint is coming out in blobs, the nozzle is probably bad.

My technique for most rattle can paints is to do what I call two "tack coats" and a "wet coat". Spray a very thin coat on the rocket, not enough for good color coverage, just enough to make a tacky surface. Wait a short time, like 10 or 15 minutes. Spray another thin tack coat on. Wait 10 - 15 minutes. Then spray the wet coat. For the wet coat, move the can a little slower than you do for the tack coats. You want to get a thicker coat, just enough for the paint to "self level" to a smooth surface, but not thick enough to run. It takes practice, but if you watch very carefully, you will see the paint begin to level out to a glossy surface. I think that having the tack coats help this process of self-leveling. Also any overspray that lands on the rocket, but isn't thick enough to self level is going to be rougher than the parts with a good wet coat. So try to finish the entire rocket's wet coat quickly, so it can all be wet at once. Even then, the last part painted will probably be the best, so try to finish on the rocket's "good side".

For a really nice glossy surface, let the color coat FULLY dry and cure --- give it a few days or a week. Then clear coat it. You can use the same tack coat/wet coat technique for clears.
 

rstaff3

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That's me. I have tried off an on to get the perfect finish. Then some other project idea pops up and I give up. Or I get bored. Or I screw it up.
 

snrkl

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I watched these last night - I certainly thought it was interesting... myths, mistakes and misconceptions in spray painting..

[video=youtube;7he7VBJaJ_E]https://www.youtube.com/watch?v=7he7VBJaJ_E[/video]

and

[video=youtube;upbuhfbXlSU]https://www.youtube.com/watch?v=upbuhfbXlSU[/video]
 

Rktman

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light mist coat first, then medium/wet coats. if, when i get OP( on a rocket), i make a decision- am i ok with it? if yes, leave it alone. if no, sand with 800 grit and add another coat or paint. or if i didnt break through the paint, add a few coats of clear.
if ya want to sand and buff, we're going to have to know more- what grit did you use to sand with( super fine could be anywhere from 400 to 4000 grit),what compound used, and what method for buffing.
toothpaste is for brushing teeth and baking soda for keeping the fridge smelling good. :)

atomization is a good thing, but i can get OP even if im using my devilbiss copper tekna if im not laying down enough product.
I was using a worn out 400 grit paper, but I'm guessing from what you said it should be a whole lot finer. I used Turtle Wax brand polishing compound but it didn't get the "orange peel" removed--probably not abrasive enough.
 

Rktman

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Originally Posted by Nathan

No, here's how . . .

https://www.rocketryforum.com/showthr...ummer+vacation


Wow, just wow Nathan. Far more patience and time than I care to spend on my rockets. They get beat up after a few launches, so I go for the 10 foot paint job. If it looks good at 10 feet, its good enough for me.
Now that is an impressive finish! Show car quality, but worth it for a larger HPR model. Admittedly I'd be nervous about flying something that beautiful...
 

Rktman

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Thanks everyone for all those important pointers. Didn't realize humidity and temperature made that much difference, nor did I realize sandpaper came in such super fine grits as 1500 and 2000 for wet sanding. My other take away is that enamel has to cure for at least a couple of days before being wet sanded to remove "orange peel" and other imperfections. Guess the other major ingredient here is patience.
 

modeltrains

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My other take away is that enamel has to cure for at least a couple of days before ...
Yep; have seen cans of basic, no-fancy-frills, spray enamels where directions say to allow a week.
A variation on the allow a week theme is to do so before recoating, as on this can of flat white Walmart label enamel.



But you probably won't have the best success with sanding in less than 4 hours.
 

Flyfalcons

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Honestly, my best finishes have come from hours of wet sanding, progressively getting to 2,000 grit, and clear coated. Sometimes my paint work comes close enough that I don't feel that wet sanding is worth the effort, and some colors seem to lay down easier than others.
 

Nytrunner

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Lots of good advice further up the page.
Don't think I'll ever move to 2000 grits and polishing compound like the Nathans of the world though.

I don't go for the mirror finishes (my rockets get seen when I'm carrying them from car -> pad, and once they're on the pad), so I will allow myself a little fudge with the temp humidity.

Humidity and cold can be a killer.

If its a little too cold, but the humidity is good, I'll spray and run it inside.
If its a little too humid but the temperature is good, I'll spray.
 

Rktman

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Honestly, my best finishes have come from hours of wet sanding, progressively getting to 2,000 grit, and clear coated. Sometimes my paint work comes close enough that I don't feel that wet sanding is worth the effort, and some colors seem to lay down easier than others.
Guess I'm looking for a compromise between impressive and "I'm never flying this piece of perfection it's too magnificent". I will give wet sanding with ultra fine grit (1500 - 2000) a try though to smooth out the irritating "orange peel" and the roughness from the inevitable pieces of pollen and dust that always find their way onto the paint surface.
 

Rktman

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I'm really beginning to see what a big difference humidity and temperature makes. Now I consult the weather forecast for the best time of day to attempt painting. That and several passes with a Swiffer Dust Cloth to ensure as much dust, grit, and pollen are removed before the paint ever touches the surface.
 

Micromeister

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Wow guy's:
Mirror glass smooth finishing isn't all the difficult if you remember that Finishing takes up to 4 times as long as building your rockets.

First: Prep work is all important: I've stopped using seam & wood fillers perferring to use only the Cheapest rattle can grey auto primer I can get my hands on. Currently that is "Fresh & Easy" from Walmart (.98/12oz can - in 3 case orders). 3 Coat, let dry overnight then sand with 220 -240 DRY sandpaper. If those first 3 coats leave some grain or seam lines showing, repeat with 1-3 coats and sand with 320-360 DRY sandpaper. In is not necessary or wanted to sand our primer any finer than 360 grit. We Want some micro peaks and valley's to give the color coats a little "tooth" to grip onto. We want our finished Primer to be free of blemishes, dust, dirt,hair or there impurities but NOT so slick that the color coats have nothing to clinge too.

As Others have mentioned, Rattle can paints are not the worlds best paint/thinner/vehicle formulas. All these Rattle Cans are intended for consumer use. As such there are some tradeoffs that had to be made. One of these is the paint consistancy. Professional painters use their experience to thin a give paint to the proper "drip rate" to get the material to flow out to a smooth coat. Unfortunately all pigments do not thin the same and Rattle Can paints are made to use the same amount of solvent thinners and spraying vehicle. So all colors do not spray the same.
All that to say it isn't always the humidity or your technique that cause some Orange Peel outcomes. It happens to the best of us using Rattle Can Products.
What to do? Wet sanding the final coating is one option. but you DO NOT need to exceed 600grit when Wet sanding on our model rockets. On a Classic Car top coat/clear coat finish you would use the finer 1000, 1200, 1500 and 2000 grit wet paper but on Model rockets it is NEVER necessary!
After Wet sanding out any dust, lint or other debris collected during the painting process with up to 600grit wet sand paper the next step to a babies butt smooth glass like finish is a 3m product "Finessit-II" polishing medium. This is NOT a rubbing compound. it is a finishing medium with ultra fine removal properties. Use as directed on the lable. Finessit-II does remove a very small amount of paint so if your model has multi colors with only a single coat be very careful as you may remove that single coat in the buffing process. On Trains, Planes, Trucks & Cars we use an electric buffer. On our Model Rockets this application and buffing process is done with very soft cotton rags by hand.
As I mentioned before this Finessit-II process does take some time. but Finessit-II will remove the worst Orange Peel you can produce Leaving a Mirror smooth finish, so time well spent it is worth it. If you have created "Paint Dams" at your multi-color seperation lines Finessit-II will remove them to the point you will not be able to feel the joint. I've done 6 and 7 color camo. paint jobs the Feel as smooth as a single color coat.
A couple examples below: All produced in my basement spray booth, using only Rattle Can paints. a little wet sanding and Finessit-II before decals and Pledge with Future protective coating.

If you would like more detailed prep, paint and finishing tips; a visit to www.narhams.org could be of help. in the left hand menu look for the Library section, when you click on Library look for Tech Tips. Tech Tip-002 through 005 will take you from Raw Wood and paper to babies butt smooth finish with lots of options and products discussed.

003d-sm_Goblin Rebuild Complete_02-10-08.jpg


147a1-sm_SS-N-2  Styx_11.346_01-12-94.jpg


176a-sm_Omega 2-stage w Cineroc_10-22-95.jpg


326a_Micro Yellow Jacket_11-17-06.jpg


672a_Orion (Kc-8) Decaled & Complete_02-10-08.jpg


170-sm_F104-G-StarFighter-32nd PMC_09-07-95.jpg


661a_Shuttle Intrepid 2pic Complete_05-20-07.jpg


664a_Triskelion (Fliskit)_05-07-07.jpg
 
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Screaminhelo

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+1 for what Mm said.

Unless I'm painting a Pinewood derby car, I don't go above 400 grit on color coats and I usually don't clear coat. If I want a shiny finish without clear, I'll sand my base color coat with 360-400 until smooth and even and re-spray if I sand through the color coat and repeat as needed (a second round is usually sufficient unless I really goofed on the surface prep). If you get the surface prep right, you won't have to re-spray and can go straight to the finish coat.

If I am going for a good gloss finish, I warm the can in hot water just before I spray.
I fill a pot with water so that it comes 2/3 to 3/4 of the way up the can and bring the water to just below a boil (without the can). The can now goes in until the top is very warm to the touch and the can is a little hot but not uncomfortable to hold, then I go spray. Doing this seems to help quite a bit with variations in weather. I have sprayed in the cold (get the rocket inside immediately after spraying) and wicked southeastern summer humidity. It is not foolproof but it works for me.

If it is a multi color job it is a bit of a different story.
I clear over everything with Rusto UV resistant clear. If is not destined for a fine finish, it gets left at that. If it is destined for a good finish job I now lightly wet sand with 800 grit to help even out the paint a bit and repeat the process of clear coat and sanding until I have the shine that I am looking for. This is followed with the automotive wax of your choice. Honestly, I have never used the full clear treatment on a rocket but I have had some Derby cars that had a gorgeous "wet" finish. The drawback with this whole process is that the finish tends to be kind of brittle in my experience.

If I were to boil all of this down to one thing that is worth repeating routinely it would be to warm the paint.
 

Rktman

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Wow guy's:
Mirror glass smooth finishing isn't all the difficult if you remember that Finishing takes up to 4 times as long as building your rockets.

First: Prep work is all important: I've stopped using seam & wood fillers perferring to use only the Cheapest rattle can grey auto primer I can get my hands on. Currently that is "Fresh & Easy" from Walmart (.98/12oz can - in 3 case orders). 3 Coat, let dry overnight then sand with 220 -240 DRY sandpaper. If those first 3 coats leave some grain or seam lines showing, repeat with 1-3 coats and sand with 320-360 DRY sandpaper. In is not necessary or wanted to sand our primer any finer than 360 grit. We Want some micro peaks and valley's to give the color coats a little "tooth" to grip onto. We want our finished Primer to be free of blemishes, dust, dirt,hair or there impurities but NOT so slick that the color coats have nothing to clinge too.

As Others have mentioned, Rattle can paints are not the worlds best paint/thinner/vehicle formulas. All these Rattle Cans are intended for consumer use. As such there are some tradeoffs that had to be made. One of these is the paint consistancy. Professional painters use their experience to thin a give paint to the proper "drip rate" to get the material to flow out to a smooth coat. Unfortunately all pigments do not thin the same and Rattle Can paints are made to use the same amount of solvent thinners and spraying vehicle. So all colors do not spray the same.
All that to say it isn't always the humidity or your technique that cause some Orange Peel outcomes. It happens to the best of us using Rattle Can Products.
What to do? Wet sanding the final coating is one option. but you DO NOT need to exceed 600grit when Wet sanding on our model rockets. On a Classic Car top coat/clear coat finish you would use the finer 1000, 1200, 1500 and 2000 grit wet paper but on Model rockets it is NEVER necessary!
After Wet sanding out any dust, lint or other debris collected during the painting process with up to 600grit wet sand paper the next step to a babies butt smooth glass like finish is a 3m product "Finessit-II" polishing medium. This is NOT a rubbing compound. it is a finishing medium with ultra fine removal properties. Use as directed on the lable. Finessit-II does remove a very small amount of paint so if your model has multi colors with only a single coat be very careful as you may remove that single coat in the buffing process. On Trains, Planes, Trucks & Cars we use an electric buffer. On our Model Rockets this application and buffing process is done with very soft cotton rags by hand.
As I mentioned before this Finessit-II process does take some time. but Finessit-II will remove the worst Orange Peel you can produce Leaving a Mirror smooth finish, so time well spent it is worth it. If you have created "Paint Dams" at your multi-color seperation lines Finessit-II will remove them to the point you will not be able to feel the joint. I've done 6 and 7 color camo. paint jobs the Feel as smooth as a single color coat.
A couple examples below: All produced in my basement spray booth, using only Rattle Can paints. a little wet sanding and Finessit-II before decals and Pledge with Future protective coating.

If you would like more detailed prep, paint and finishing tips; a visit to www.narhams.org could be of help. in the left hand menu look for the Library section, when you click on Library look for Tech Tips. Tech Tip-002 through 005 will take you from Raw Wood and paper to babies butt smooth finish with lots of options and products discussed.
Can primer really be used to fill in grain lines and body tube seams? First I've heard, but that would be a real time saver.
 

Rktman

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+1 for what Mm said.

Unless I'm painting a Pinewood derby car, I don't go above 400 grit on color coats and I usually don't clear coat. If I want a shiny finish without clear, I'll sand my base color coat with 360-400 until smooth and even and re-spray if I sand through the color coat and repeat as needed (a second round is usually sufficient unless I really goofed on the surface prep). If you get the surface prep right, you won't have to re-spray and can go straight to the finish coat.

If I am going for a good gloss finish, I warm the can in hot water just before I spray.
I fill a pot with water so that it comes 2/3 to 3/4 of the way up the can and bring the water to just below a boil (without the can). The can now goes in until the top is very warm to the touch and the can is a little hot but not uncomfortable to hold, then I go spray. Doing this seems to help quite a bit with variations in weather. I have sprayed in the cold (get the rocket inside immediately after spraying) and wicked southeastern summer humidity. It is not foolproof but it works for me.

If it is a multi color job it is a bit of a different story.
I clear over everything with Rusto UV resistant clear. If is not destined for a fine finish, it gets left at that. If it is destined for a good finish job I now lightly wet sand with 800 grit to help even out the paint a bit and repeat the process of clear coat and sanding until I have the shine that I am looking for. This is followed with the automotive wax of your choice. Honestly, I have never used the full clear treatment on a rocket but I have had some Derby cars that had a gorgeous "wet" finish. The drawback with this whole process is that the finish tends to be kind of brittle in my experience.

If I were to boil all of this down to one thing that is worth repeating routinely it would be to warm the paint.
I just tried wet sanding with 1500 grit and it dulled the paint finish, taking off whatever gloss there was. Wouldn't using a rougher grade like 400 or 800 yield even worse results? Or do you mean you spray a final color or clear coat after this final sanding?
 

neil_w

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I just tried wet sanding with 1500 grit and it dulled the paint finish, taking off whatever gloss there was. Wouldn't using a rougher grade like 400 or 800 yield even worse results? Or do you mean you spray a final color or clear coat after this final sanding?
Yes, you must polish and/or clear coat after sanding. Sanding alone will not yield glossy finish.

Alternatively, you could apply a final coat of paint after sanding. I've found that gives predictably good results, but I am curious to try finesse-it and see how it behaves.
 

ThirstyBarbarian

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Can primer really be used to fill in grain lines and body tube seams? First I've heard, but that would be a real time saver.
It can if it is a filler primer, not just a primer for paint adhesion. I've used the Rustoleum Filler Primer with good result, but it does take a few coats and a lot of sanding. Now I typically use a wood filler first for big, deep spirals. Sand that to a semi-decent finish, then use the filler primer.
 

neil_w

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It can be done with this: Micromesh Polishing Kit
Followed by this: Novus Plastic Polish

In the end, sanding with 400 grit followed by a good top coat can get a pretty slick finish with much less work.
That's been my most successful approach, although I usually finish with 800 grit, because I'm afraid of hacking off too much paint with the 400. But a first few light coats of paint, followed by one session of wet sanding, followed by a final heavy wet coat has produced really good results for me 100% of the time so far. Whereas, trying to get a good paint job in one shot has been successful only about 25% of the time.

Thinking more about Micro's advice, my only problem with that would be that when I sand, I usually sand all the way through paint in a few spots, usually edges. So I almost always need another coat of paint on top, and then at that point it's usually good enough that I don't really need to bother with further sanding and/or polishing. Mind you, I'm not going for a showroom mirror finish.
 

Nathan

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I just tried wet sanding with 1500 grit and it dulled the paint finish, taking off whatever gloss there was. Wouldn't using a rougher grade like 400 or 800 yield even worse results? Or do you mean you spray a final color or clear coat after this final sanding?
Yes wet sanding removes orange peel texture but leaves a non-glossy finish. You have to polish after wet sanding to make it glossy. But wet sanding should be done with 1500 - 2000 grit sandpaper, not 400 grit. Don't take my word for it, go read about wet sanding on any autobody forum. It would be a lot of work to thoroughly polish out 400 grit scratch marks.
 
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