I would use denatured alcohol for thinner rather than

water.  Add the alcohol until it seems about right, then spray it on a piece of scrap and see how it comes out.  If it is to thin, more like a stain, add paint.  If it is still too thick, add more alcohol.  I used some craft paint with alcohol, but it has been so long ago that I don't remember the proportions that I used.  By the way I prefer denatured alcohol as opposed to isopropyl because I have had experience with the paint shocking &  clotting with isopropyl.

Hi Richard.  I’ve used craft

Hi Richard.  I’ve used craft paints.  They have to be thinned with either an airbrush thinner you can buy or a homemade formula.  I suggest you search YouTube for both the formula for a homemade thinner and for tips on airbrushing with craft paints.  The finish is quite rough texturally.  I’d practice on plastic spoons or scrap styrene before trying it your structure.  50-50 is probably the minimum ratio.  I think I’ve probably used something closer to 65-35.  The advice seems to always thin it to the consistency of milk.  Good luck.

Dan Aguilera 

Craft Paint

I bought Airbrush medium from a art supply store (Blick) and mix that with the craft paint and touch of ethanol for thinner.  I also buy the "name brand" craft paints that have more pigment and start out thicker.

Richard

 I use tap water straight from the kitchen sink with no issue Richard.

Windex, I use windex and

Windex,

I use windex and distilled water, to thin and clean.  50/50 mix,by guess

''my'' tap water won't work, and I found alcohol will crudle the pant.

Go to U Tube look for air brushing craft paint, all kinds of info

Hi Richard, the June 2015

Hi Richard, the June 2015 issue of RMC has a very good article Using Craft Paint by Gregory M. Larocca for painting rolling stock. He adds a bit of artist quality flow enhancer and sometimes a bit of clear acrylic medium. As others have said, alcohol can cause some acrylics to curdle and too much thinning with water reduces the acrylic binder in the paint that can affect adhesion.

Actually, what I do is to

Actually, what I do is to thin the craft paint with 50% Liquitex Acrylic Airbrush Medium, and approximately 4% Liquidtex Flow-Aid (e.g. 1 mL into 25 mL paint/airbrush medium in a one-ounce Floquil bottle.  I have been using this in lieu of any "model" paint with very good results, including painting brass.

Some things I figured out after the RMC article was published were to use Gloss Medium or Matt Medium thinned the same as the craft paint as clear coats for decaling and finishing models, and dry-wall primer (!), again thinned the same as craft paint as a primer.  It sticks really well to brass, as well as giving good "tooth" on plastic.

I have come to prefer the Deco-Art Americana line of paints.  There are hundreds of colors, they are available in many places, and are high-quality.  For detail parts, figures, and structure components that I want to brush paint, I have been using the craft paints right out of the bottle.

Greg LaRocca

Home made Thinner for Walmart acrylic craft paint

Here is what I use to shoot the cheap Walmart acrylics through my airbrush with great results:

• 12oz Distilled Water
• 4oz Denatured Alcohol
• 4oz Window Cleaner
• 10 drops of Glycerin

I mix this concoction 20oz at a time and fill up a gallon jug to have on hand. I am sure there are many that are smarter than I that can figure out the measurements to make a gallon at a time instead of mixing and pouring 20 oz. at a time...but I am not that smart.

For brush painting I use 70% alcohol. I had a lumpy experience when experimenting with 91% alcohol. The 71% seems to work better for washes as well as brushing to cover surfaces entirely.

One very important piece of equipment to have is...a small battery operated paint mixer. This little item is wonderful and is especially good for the cheap paints that I use.

Pledge/Future is your acrylic friend

I recently learned that many military modelers have been airbrushing inexpensive craft acrylics thinned with Future Floor Finish, a.k.a. Pledge Floor Care with Future shine.  Mix the Pledge/Future about 50:50 with distilled water, then use that mixture to thin the craft acrylics to thin the paint to the "milky" consistency that airbrushes like.  The proportion of thinner needed to achieve this varies a bit with the paint brand, batch and age.  Pledge/Future seems to achieve some of the emulsifying, self-leveling, and finish strengthening effects of the more expensive artists' additives mentioned above. Simple, and it does work pretty well. In my experience the results are more variable and a bit fussier to deal with than airbrushing with high quality, fresh model paints.  But at a tenth to a quarter of the cost,  and ingredients you can shop for so easily, it can be worth it. 

Model Railroad Hobbyist

has a great guide to acrylic painting created by Joe Fugate. Another valuable resource from MRH.

https://model-railroad-hobbyist.com/subscribers-only/painting/acrylics

Everything you need to know. Enjoy. Glenn

Airbrushing Craft Paint

Thanks to all of you that replied. Your input has given me a really good place to start.

Richard

Cheap Alternatives

Long time ago when I painted by the 55 gallon drum daily we used a product called " Floetrol ". Today you can get it by the quart and each quart treats about 4 gallons of paint. How far a quart would go in modeling acrylic paint is anyones guess. I also use distilled water as most of the impurities are removed ( those are what causes most drying rings on your car after you wash it - simplied example of paint drying ). 

Floetrol helps with latex and acrylic paints to flow and lay down better..makes them a bit more managable out of airbrushes, reduces the incidents of drying on the tip/cap however it makes the drying time last a bit longer. The product will also reduce the gloss in full on gloss coats a bit. The product can be found at large hardware stores and almost any building supply store near you. The picture come from the " Home Depot " web site. BEWARE  - there are two versions, one for latex acrylic and one for oil based products. Usually the latex based comes in a plastic bottle and the oil based comes in a metal can. BE CAREFUL which one you might pick up.

I have used craft style acrylic paints to paint about 1200 various scale miniatures ( 15mm to 32mm scale ) and structures/terrain in the last 10 years. Yes they do have a bit more texture..but when I am adding shading or other applications to the base paint..I have a bit of " tooth " for those same acrylic mixtures to adhere to. Covering with a matte clear also has a better chance of adgereing and not chip or flake off. I use the craft type acrylic paints on items that have been primed with " self-etching " spray bomb caned primers found at Wal-Mart as well.



 

"name brand"

Dave,

What do you consider the "name brand" paints. Seems like the collection at Michael's keeps growing.

Chris

tap water varies in mineral content all over the country.

If someone has used tap water and had no problems, they are lucky enough to live where the tap water is fairly free of minerals.  In other parts of even the same county the tap water may have so much mineral content that you would get mineral deposits in the paint when it dries.

Consider Straining

One tip that nobody has mentioned yet - strain the paint after thinning.  Most of the time most of the paint will airbrush just fine without it.  And, dry tip is more common with airbrushing acrylic paint in general whether strained or not.  But occasionally you may get a clog.  Adequate thinning and good pressure usually overrides clogs with acrylic, but sometimes leads to a great big splat as the clog clears onto the model.  Micro Mark sells a nice set of strainer funnels.  I have come to rely on them and it is remarkable what will remain in the mesh after straining.

Galen

Craft paints fine for brushing but troublesome for airbrushing

I know I'm going against the grain here, but I would recommend acrylic craft paint only for regular brushing. The quality doesn't make a significant difference with the thickness of the coat you get from a brush, unless you happen to use a fairly transparent color (like a bright yellow). It isn't as well-behaved or cover as well when pushed through an airbrush.

Airbrushing works much better and easier with paint made for airbrushing. It is formulated as a smooth mixture for easy application, has a higher pigment concentration to retain its color in a thin coat, and the pigments (few or none are made with dyes) themselves are ground finer and help avoid clogging your equipment. Most can be thinned up to 1:1 with (distilled) water, when it requires thinning, but your best results will be to use an airbrush medium that doesn't diffuse the binder and usually includes other additives that smooths the flow for more uniform coverage.

My preference is for Golden airbrush acrylics (small bottles of liquid paint) that you can get in better art stores or online. Sure they seem expensive but you don't end up using much. My projects are worth the little bit extra to avoid the hassles that come with using cheap paint.

Craft paint shortcomings

Negative Nellie!

Wow Joe, you sure are against using Craft Paints aren't you?  No doubt from your vast experience using them on model railroad rolling stock, yes?.  My experiences are from using craft paint over the last seven years--I have yet to see any substantial difference between craft paint and "model railroad' paint.

Let's look at each point you raise:

1)  "Not as colorfast"  Perhaps in intense sunlight that is true, but I don't run my model railroad outdoors.  I do run it under fluorescent shop lights with daylight tubes, and no UV filtering.  My observation is that there is no difference in color or intensity between a freshly painted model and one that has been on the layout for years.  This is true of both models painted with craft paint and those painted with traditional model paints.  

Here's an experiment you can try at home that would yield hard data as to the colorfastness of paints and the effects of fluorescent light on model paint..  Take some plastic pieces (you'll need six) and paint one set with craft paint and the other with whatever acrylic you prefer.  Now place them as follows--one pair (craft paint and acrylic) as close to a fluorescent tube as possible, one pair somewhere on your layout which is an average distance from the fluorescent lights, and one pair in a light-tight container, drawer, whatever will keep them dark.  Wait one year.  Compare.  I haven't done this, so I don't know what will happen to the pair on the fluorescent light (probably there will be fading of both, although the UV is less of a problem than many people think, else we'd all be getting tans while working on our layouts), but I am certain that there will be no differences between the pair on the layout and the pair that was kept in the dark. 

2)  "Final finish is soft"  Really?  My layout is such that I use a fiddle yard to set-up and take-down trains, so my equipment is being handled all the time.  My passenger cars live in A-Line boxes, so they have the additional stress of rubbing against the cardboard row separators.  I have not seen any wearing of paint from my equipment that has been finished with craft paint.

3)  "Try to avoid mixing colors"  Okay, I am baiting and switching here, since I don't have a way of measuring the concentration of pigment in a bottle of craft paint, but this statement about mixing colors misses the whole point (and beauty) of using the craft paints--you don't need to mix them to get a specific color, because there are so many different colors available that there is sure to be one as close to the color you want as you would get by mixing.

4)  "The stuff is cheap inexpensive for a reason!"  FIFY.  Has it ever occurred to you that craft paint might sell for far less than model paint because the market is so much bigger?  I mean, come on man, we've lost Floquil, Polly-Scale, Model Master, Pactra, and whoever else in the last several years because everyone wants RTR and doesn't want to have to build and paint their own equipment.  There is no market for model railroad paint.  If  there were, these brands would still be available.  But, I can walk into Michael's, JoAnn Fabrics, my local hobby shop, even my local hardware store, and they have craft paints.  How many Michael's are there in the US?  How many crafters are there verses model railroaders?  Lots more, I'll wager.  Remember, volume = discount.

Joe, I am publicly challenging you to go out, buy some craft paint, use it per my article in Craftsman, run whatever you paint on your layout the way you use your other equipment, and then tell us what you think.  I take my model railroading very seriously, and I wouldn't be using craft paint if I thought it were substantially inferior to Polly-Scale.

Respectfully,

Greg LaRocca

@MrBandO

Greg, first of all, keep in mind text-only posts that are the least bit negative tend to come across as far more negative than intended. I'm actually not as negative as it might seem, so please relax! Also, it's okay to agree to disagree and still be friends (wink). I don't mind, and I hope you don't either.

First, I do use craft paints on my layout, but I will never use craft paints on my rolling stock or locomotives as the base coat. I figure if I pay $250 for a nice loco or $35 for a nice piece of rolling stock, I'm not about to wimp out and use a $1 bottle of paint on it. I will get a quality paint ($2-$3 per bottle, still won't break the bank).

Where I do use craft paints:

1. I use craft paints for weathering, including on rolling stock. I don't care if the colors fade, get muddy when mixed, or dry soft. I prefer not to use craft paints for loco weathering, however.

2. I use craft paints to paint scenery. I don't care if the terrain or rock colors might fade over time. Eh, big deal.

3. I use craft paints to paint details like barrels, fire hydrants, sidewalks, roads and road stripes, and so on. Again, possible fading later doesn't concern me.

4. On many structures, I have no problem using craft paints to paint them. Again, if the structure fades, so what.

5. I have used craft paints to weather my track ties. Again, I am not particularly concerned if the colors fade over time.

One reason I'm not too worried about fading on these things is because a good coat of dust will fade them far quicker than any pigment fade might happen. I am not going to go around my layout every 6 months meticulously cleaning the dust off every inch of ballast, off every rock, or off every structure surface. I just won't!

Keep in mind I'm talking about using craft paints straight. In all the use cases I list above, I use the craft paints straight, or thinned with one of my thinner formulas in the MRH Acrylic Guide.

Upgrading the paint base like you do with a quality artists acrylic medium acknowledges that these paints as they come fall short. Using a quality acrylic medium (not cheap) upgrades the craft paint into the realm of what I would call a student grade (low level artist's grade) acrylic. The pigment quality is lower on student grade acrylics (less pricey) versus top level artist grade acrylics (more pricey). See this YT video for a comparison: 

So you're actually doing just what these cheap paints need with your upgrade formula. But you're adding to the cost of the paint when you do that. I get that the total cost is still less than quality model paints, so in a pinch, that's certainly a budget painting option that's far better than using the craft paints straight.

However, if I care about the thing I'm painting getting the best quality finish possible (locos, rolling stock, key structures), I won't use craft paints, not even your upgraded craft paints, for that. I list my reasons in my previous post. On that, we probably just need to agree to disagree.

P.S. This Youtube video I reference above does some quick comparisons of cheaper acrylics to more expensive artist acrylics ... and suggests some tests we could do with model paints vs craft paints ... like the coverage test. I may do those tests one of these days and document the results. 

I buy undecorated figures to "people" my railroad.

Prieser undecorated figures are a fraction to the price of their hand painted figures.  Since most of my model railroad equipment is used on a modular club layout, most of the people are used as engine crews or passengers in passenger trains.  I want "dead flat" paint for clothing and skin tones.  Craft paints are flat, and designed for brush painting.  

It doesn't make any

It doesn't make any difference to me if someone wants to use craft paints in their airbrush. It might work in some circumstances.

However, be aware that the pigment in craft paint is about the size of a boulder compared to the fine ground pigments in decent quality paints.  Adding all of the artist's medium on the shelf of the art supply store and it won't make that pigment any smaller.

This may make no difference for your application. But you might want to try it first.

gs