Basics. Airbrushing.

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Basics. Airbrushing.

Post by TER-OR »

Please use this thread to discuss basic airbrushing issues and techniques.
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Post by Less Than Super Ostrich »

I have a Badger Anthem 155 and I use about 20 PSI. I believe the equipment is in good working order, but I can't seem to get the fine lines needed to do a proper post shading technique.

I use Tamiya acrylics with just a small bit of Tamiya thinner (probably in the ratio of 1:8 Thinner:Paint). Do I need to thin down the paint more?
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Post by TER-OR »

You're probably running at too high pressure and too thick paint, Brian. Experiment with a thinner mixture and dial your pressure back some- it will take some time.

The 155 is a good brush for pretty fine lines. It's essentially similar to my Omni 3000, and there's few things I can't do with that.
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Post by Anavel65 »

Hi, I also have a Badger Anthem 155 and recently I've been having a problem of water bubbling around the tip and spraying out when I paint. My air compressor has a moisture trap that is working properly on it. The water is bubbling on the outside just behind the tip of the nozzle and then spraying out of it. I'm confused as to why this started. When I clean it out between paintings I always let it dry for at least a couple of days.
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Post by MGMorden »

The little water bubbles build up in my T&C Vega 2000 as well (I also have a moisture trap installed inline on my hose). I always just point it to a piece of paper and press the button once before starting to paint an area. A little paint will usually dislodge from the inside of the brush and splatter on the paper, and then I can move onto the model itself and it'll be good for a while. I then just point it the the paper every now and then and press for air (but not paint) and let any water come out that way. Occasionally I'll still get a water spot, but it's rare and I've learned to live with it. There's no way I'm gonna strip a paint job over one spot :).

Incidentally, I've learned the trick to a nice paint job when airbrushing is keeping the pressure low. 10-15 psi is good with properly thinned paint (heck Testor's Acryl is good out of the jar at that pressure). The paint goes a LONG way at this pressure and you can build up several nice LIGHT coats for a good smooth finish. I also always use a color cup rather than jars. It's quicker to load up and you can add less paint to it and get it to spray. After finishing I take a syringe w/ water, spray it into the cup, and then suck the water back up and spray it back in w/ the syringe until it comes clean (you can angle the needle to jet water across remaining paint and work it off). After the cup looks clean, I'll spray 1 color cup full of alcholol through it at 15psi, and another at 40 psi. It's usually clean after that.
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Airbrushing Transparent Green, a problem!

Post by DarKev »

Hello Folks!

I'm trying to create a Metallic Green effect for a Star Trek Model I am building and I running into a bit of an issue. I applied a coat of non-buffing aluminum to the model and let it dry and then airbrushed it with Tamaya Transparent Green. Well the Green collected in this "splotches" and for the life of me I can't figure out why. Note, I did the same thing with a Bandai chrome-stripped MG Shiki Mobile Suit model (but used transparent yellow) and it worked fine.

Anyone got any suggestions!!!

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Post by Kylwell »

Almost sounds like the green wasn't mixed thoroughly.

It could be as simple as the transperant green is a darker pigment than the yellow and therefore the flaws show up more visibly.
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Airbrushing Gouache

Post by zaphod »

Airbrushing Gouache:

I want to start using gouache here and there on my models, because of the lightfast/colorfast pigments, and am not sure how much to thin them.

These paints have about the same consistency as oils or watercolors and come in little tubes. Has anyone thinned such or similar paints for airbrushing? Any thoughts?

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Post by Kylwell »

You'll want to use a retarder for airbrushing guache(?) as it usually dries too quick if you thin it with just water.

What type if Gouache are you using?
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Post by zaphod »

I'm using Windsor & Newton, which is a misture of pigments, gum arabic, and a little water.
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Airbrushing Gouache

Post by zaphod »

I've found something which may shed some light on this topic:

"CACY’S CORNER
with Michael Cacy

Thoughts About Painting Gouache Through an Airbrush

I recently fielded a question in Airbrush Action magazine from someone who was having problems airbrushing with gouache. While the question seemed simple enough, I was a little surprised at how much information it took to respond. Lengthy as my reply became, as one avenue opened up yet another, some potentially useful points were raised which might--one of these days--be of use to you.

Gouache (pronounced "gwash") is an opaque watercolor medium that will paint beautifully through an airbrush, but there are a few unique qualities to this paint that you should bear in mind. Always insist on the finest quality materials available. I normally use Winsor & Newton Designer Gouache, but have used other brands, as well. This medium is one of the most opaque paints that we can apply with the airbrush, and it will cover an existing area even quicker than opaque acrylic media. The difference here is that when dry, gouache remains water soluble, while acrylics become permanent or, in theory, at least, impervious to moisture.

Don't confuse gouache with tempera. While both are opaque water-base paints, the pigments in tempera are milled (or ground) more coarsely. If one were to spray tempera through an airbrush, it would be almost impossible to prevent the atomized pigment from air drying (turning to powder) before reaching the surface of the painting. The result: powdered, poorly adhered pigment lying on the surface of the art just begging to be damaged. My point in mentioning tempera is that, even though the pigment in gouache is ground finer (and is mixed with a small amount of gum arabic as a binder), the same adhesion problem can arise when using gouache if you're not careful.

Practice makes perfect, and I've learned the same way as everyone else--trial and error. If the surface of the gouache you've painted looks like suede or sandpaper, that surface is, indeed, very fragile. If this symptom sounds familiar, we need to discuss how to keep the pigment from air drying before it arrives onto the painting. Properly painted, the surface should resemble the smooth finish of a chalkboard."


"Painted gouache has poor adhesion and/or looks too fragile?

The problem may be the result of:

1. Viscosity too dense for smooth atomization. Since this paint is as thick as paste when it comes out of the tube, it is crucial to dilute gouache with water to the appropriate viscosity and mix thoroughly before you begin painting. Mixing is best done in a separate container, not in the paint cup on your airbrush. I use small Solo brand plastic cups or, if I want to store or save unused paint, plastic 35mm film cans work great because they can be sealed with a cap (and they're free from your local photo finisher). Do not mix in paper cups, as tiny paper fibers may contaminate your paint and wind up lodged in the nozzle of your airbrush. For situations where broad areas are to be painted, the viscosity should be no thicker than milk. For details, such as highlights, gouache is more easily controlled if it is slightly thicker, like heavy cream. Do NOT try to airbrush with a heavy, "soupy" mixture--or paint that has not been stirred sufficiently enough to be consistent. If you have gotten into the habit of painting with a mixture thicker than I've just described, you may need to slow down a little, making more passes with the airbrush to cover to opacity. But the payoff is a more perfect and better-adhered layer of paint. If you find that you still need to increase the adhesion, try adding a small amount of acrylic such as Com-Art Opaque to the diluted gouache. A few drops of a bottled acrylic formulated especially for airbrushing will greatly enhance the bond of paint to the working surface without changing the overall look of the gouache.
2. Working too far back from the surface to be painted. Ideally, you should strive to paint somewhere in between "wet" and "dry". The perils of painting too wet should be obvious if you've done much airbrushing, and I have already touched on what may occur if the pigment is allowed to air dry before arriving on the painting. Allowing too great a distance between the airbrush and the surface being painted usually results in powdery, air-dried pigment and poor adhesion.
3. Not enough air pressure to push heavy pigment. Gouache or opaque acrylics are media that I consider "heavy pigments." Try adjusting your air pressure at the regulator with this in mind because there is a direct relationship between air pressure and the viscosity of your paint. It will depend upon what type of airbrush you are using. (The standard Iwata models such as an HP-C, HP-B, HP-SB, or Eclipse are ideal.) But if you've had great success with transparent acrylics, inks, and dyes at 25psi, try stepping up to 30 pounds of pressure to push gouache through your airbrush. Adjust to an even higher pressure setting to airbrush very broad areas.
Once you have got A, B, and C in balance, you can be confident that you're painting gouache like a pro."

This was from:
http://www.airbrushtalk.com/abtv2n2.htm

Other thought: One definitely needs to seal gouache to protect it, given the delicate surface that results. Also, gouache dries to a very matte finish.

Guess I answered my own question. I hope my fellow modelers will give gouache a try.
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Post by TER-OR »

Paints and thinners I've found:

Tamiya and Gunze Sangyo: 99% Isopropyl alcohol. Just enough thinner to get the viscosity right - maybe 10-15%

Testors Acryl: Water, again just a bit if necessary.

PolyScale and Aeromaster: Polyscale's own thinner or a little water.


Most paints, at least acrylics, are meant for airbrushing and don't usually neeed much thinning.
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Post by Jonas Calhoun »

TER-OR wrote:Tamiya and Gunze Sangyo: 99% Isopropyl alcohol. Just enough thinner to get the viscosity right - maybe 10-15%
I've had trouble using straight IPA with these two lines of paints. They seem to dry out a bit too quick. Adding a little Liquitex Slo-Dri does help (a drop or two per airbrush paint cup). There is something in their brand of thinners though--it has retarding properties. However they both smell like IPA.

Otherwise, I think you are spot on with your recommendations. Maybe just a little surfactant (I use Liquitex Flow-Aid) with your water, but it isn't strictly necessary.

Dan
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Post by implant »

I'll post my question in the right place this time !
Just got a brand new airbrush - I'm looking for some advice on the ratio of thinners to paint when using acrylics and enamels. Also any advice on the best type of thinner for each type of paint - don't want to ruin months of work with the first coat !

Too much thinner and the paint won't cover, too little and I have visions of an enamel-encrusted airbrush after one session. I'm looking for a beginners's guide - because I'm very much still on square one when it comes to finishing/painting. :?
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Post by Kylwell »

implant wrote:I'll post my question in the right place this time !
Just got a brand new airbrush - I'm looking for some advice on the ratio of thinners to paint when using acrylics and enamels. Also any advice on the best type of thinner for each type of paint - don't want to ruin months of work with the first coat !

Too much thinner and the paint won't cover, too little and I have visions of an enamel-encrusted airbrush after one session. I'm looking for a beginners's guide - because I'm very much still on square one when it comes to finishing/painting. :?
Personally I stopped trying to make my own thinners and just buy what'er brand thinner the paint manufacturer recomends (usually their own). I use EZ Air cleaner to clean my brush, works great with just about any kind of acrylic (they also make one for enamels).

As far as thinning goes, I think it depends on paint, airbrush, and painting style. I tend to run my paints pruty thin, about 1 part thinner to 2 parts paint. White I tend to thin less and black I tend to thin more. With metalics you have to be careful about over thinning them, becuase if you do the fine metal flakes that make up the metalic part won't suspend and you loose a lot of that metalic look.
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Post by Mr. Badwrench »

I'll test spray on a napkin or paper towel. If the paint soaks in right away, it's too thin. If it gobs on, it is too thick. I want it to color the paper towel without soaking right it.

Also, Testors buffable metallizers require no thinner whatsoever. And they are the easist to clean up after. I almost never use acrylics in my airbrush, so you probably know more about them than I do.

You can run Future through the airbrush straight, but from what I've learned, it helps to thin it a little. I use Windex or amonia to thin Future. I'm still experimenting on ratio. You can tint Future with acrylics.
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Sputtering Airbrush

Post by halo556 »

I am using a single action T&C Omni for some basic coverage and it keeps sputtering. I have checked the seal in the tip assembly and valve and cleaned the bejesus out of it but nothing has worked. Any suggestions? Could this possibly be due to the internal seal in the body of the airbrush? Any help is appreciated. Thank you.
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Post by Mr. Badwrench »

Your paint may be too thick, what are you spraying?
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Post by TER-OR »

I use an Omni 3000.

It goes through tips quickly.
Odds are you need a new tip. Buy a few at a time, so you always have one ready. You will see if it's worn out when you compare it to the new one.

THe needle eventually makes the tip orifice too big.
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Post by halo556 »

I am spraying MM acrylic paint thinned to about 50/50 mix.
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Folks, what do you use to clean your airbrush???

Post by DarKev »

Hello Folks

I was wondering what you folks use to clean your airbrushes after using Acrylic Paint. I'm getting tired of paying $5.00 for bottled brush cleaner. Anyone have a more cost effective solution??

Thanks

DarKev
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Post by Jonas Calhoun »

I use a solution of Simple Green, Distilled water, and Windex. I think it's mixed 10:20:5. I found it on the Finescale.com forum. It's my flush mixture, but for the cleaning at the end of the session, I use Testor's acrylic cleaner, reduced 50% with distilled water. I haven't found anything that cuts the old paint like that cleaner.

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Re: Folks, what do you use to clean your airbrush???

Post by Kylwell »

DarKev wrote:Hello Folks

I was wondering what you folks use to clean your airbrushes after using Acrylic Paint. I'm getting tired of paying $5.00 for bottled brush cleaner. Anyone have a more cost effective solution??

Thanks

DarKev
I use EZ AIR airbrush cleaner. Yes, it's $5 for 8 oz, but the stuf is so concentrated that a single bottle will last me a year or so.

And it's "enviromentally safe".
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Post by Less Than Super Ostrich »

MGMorden wrote: 10-15 psi is good with properly thinned paint (heck Testor's Acryl is good out of the jar at that pressure). The paint goes a LONG way at this pressure and you can build up several nice LIGHT coats for a good smooth finish.
Y'all agree with this? I had been going at 25 psi... is that way too much? By the way, the usual for me is a Badger 155 Anthem and Tamiya Acrylics to Tamiya thinner ratio of 60:40.
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Post by Mr. Badwrench »

Don't know about the acrylic / thinner ratio, but yeah, 10 - 15 psi sounds about right. I used to spray on about 25 - 30 psi too, until I found out how much better it handles at lower pressures. Still learning.
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Post by justcrash »

MGMorden wrote:10-15 psi is good with properly thinned paint (heck Testor's Acryl is good out of the jar at that pressure).
Is this true? Has anyone tried this? What about Tamiya acrylics?
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Post by TER-OR »

Pretty much. I don't have a pressure guage, but I airbrush at a pretty low airflow. Acryl in a fresh jar is pretty well thinned. Often I need to thin the Gunze and Tamiya a bit, it seems once opened, they evaporate a little.

Don't spray thick coats of Acryl, though, it will crackle. Multiple thinner coats, even in the same session seem to do much better.
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Post by xamel1975 »

I need help! My airbrush nozzle tip is chipped. :( Now when I pull back the needle to paint, bubbles starts to build up inside the cup.

Is it possible if I just file away the tip, which could result larger diameter of the tip or should I get a new tip? Any ideas?

BTW, I use a cheapo Sparmax double action handpiece. Considering getting a new handpiece right now.
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Post by TER-OR »

Get a new tip. Buy a couple while you're doing so. The tip will wear down over time, and you may not notice until you try to do precision work. A worn tip may be OK for area coverage, but not fine control.

A cracked tip - is garbage. You wil have no control.
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Post by justcrash »

TER-OR wrote:Get a new tip. Buy a couple while you're doing so. The tip will wear down over time, and you may not notice until you try to do precision work. A worn tip may be OK for area coverage, but not fine control.

A cracked tip - is garbage. You wil have no control.
hey Ter, how can you tell when your tip is worn?
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