What type of wash to use with acrylic paint

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Active Member
I am taking my first stab at airbrushing structures:

I used Apple Barrel acrylic paints shot through a Paasche double action airbrush. I am pleased with the initial results. I experimented with Dullcote and another craft acrylic sealer on these structures. I want to weather with washes and eventually use chalks or powders. I like the texture affect of the chalks and powders.

My question is regarding what type of wash to use. Do I mix the paint with my home made reducer recipe at a 1 to 1 ratio? This worked great for the airbrushing. Or, do I use a mixture of alcohol ? or distilled water? Again, I was planning on using the Apple Barrel paints for the wash. One trick that really worked was applying heat after each thin coat of paint (shhh.. used the wife's blow dryer on a low heat setting)
Would this also be a good idea to use when applying the washes?


PrarieKnight - I paint with acrylic paints in my airbrush as well. For a brush-on wash I start off with just a drop or two of acrylic paint mixed with windshield washer fluid. I then adjust the mixture depending on what results I want to achieve.

I use windshield washer fluid to thin the paint in the airbrush as well.

Red Oak & Western

Active Member
Best not to use just distilled water for the wash. It can dilute the paint beyond the point of the acrylic's ability to set. Depending on your reducer's formula (mine is Butoxyethanol based), I would suggest a 50-50 base of reducer and alcohol, then add the paint. But the best route is to experiment, experiment, experiment. Use scraps, rejects, etc. for test beds.


Section Hand
I'm starting to believe that using the manufacture's thinner, while not cheap, maybe the best way to thin acrylic paints. I use a mixture of water and alcohol for most weathering projects.



I use tap water. I don't have; or, use an airbrush. We all have our own methods. I wrote a multi page article here at the Model Railroad Forums on weathering rolling stock using my method. It is located here: http://www.modelrailroadforums.com/...ith-Acrylic-Paint-Washes-previous-to-assembly

I will not pay for something to thin acrylics with, when tap water works so well. I use Ceramcoat, Vallejo and Micro-Lux paints and have had absolutely no problems using tap water to thin with. Yes, it's hard to believe that we can use something so simple when we are so used to needing to spend hard earned money to buy a thinning agent! Whether or not a special thinning agent is needed for spray painting is out of my realm.
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Active Member
I appreciate the advice and suggestions. I wanted to post a few before/after pictures of my first efforts. This is after five washes with different shades of grey. I plan on using a couple different shades of brown. I used craft acrylic paints with 70%alcohol

Grain and Lumber 10.jpgLumber weathered10.jpgGrain and lumber after weathering10.jpg



Tom Stockton
Up to now, my acrylic thinner of choice has been tap water with just a teeny-tiny touch of Dawn dishwashing detergent (breaks down the surface tension so the thinned paint will flow better). But I've seen more and more folks talking about using windshield washer fluid as a thinner.


1) Do you use it just like water -- adjusting how much depending on paint thickness?

2) Would you recommend still using that tiny bit of Dawn to break down surface tension?

3) Cheap brands okay, or should I spring for "the good stuff"?

Thanks in advance!

Tom Stockton
Tom, I would experiment and go with what works for me.
I have messed up several "junk" boxcars before I have a technique that satisfies me.

Painters of miniature fantasy figures, like fairies and dragons, are a good source of information about Vallejo and Micro-Lux. They need fine pigment paints that will take washes to show more details in their figurines. Search youtube for info. They tend to use the thinner suggested by the manufacturer. The comment about destroying the bonding agent is important with these better paints.

If I used inexpensive Apple Barrel paints, I would be inclined to experiment with darn near anything.

  • Water thins.
  • Alcohol thins and reduces viscosity and dries faster.
  • Detergents increase "wetting".
  • Anti freeze is a common wetting agent in commercial thinners. In antifreeze, propylene gylcol is non-toxic, ethelyne glycol is toxic. I feel safe using either because the quantity is so small and my paints are out of reach of my dogs and any children.
  • Armor-all glass cleaner is 1% propylene glycol according to their MSDS, and has been used successfully by some model railroaders (reference here )

For black wash on rolling stock I prefer india ink thinned with 70% or 90% isopropyl alcohol.
I have successfully used colored acrylic paints for washes for rock castings, thinned quite a bit with 70% isopropyl alcohol


Active Member

I am finding that using 70% Alcohol works fine for making a wash with the cheap Apple Barrel paints. The thing is to experiment with is the amount of alcohol that you use depending on the color that you are using. I generally start with 2 ounces of paint (one entire plastic bottle of Apple Barrel) in an 8 ounce plastic cup. I then add about 6 or 7 ounces of the alcohol. The other investment that has paid off with all of the experimenting is a battery operated paint mixer. After mixing thoroughly I can see if the pigment has either mixed in well or separated to where I throw out the mixture and start over. I mainly use the matte black, pewter grey, and burnt umber for the washes. I apply this with a brush to structures and scenery.

What I need to experiment with is shooting Apple Barrel through my Paasche to weather rolling stock. I have seen some very good weathering on rolling stock by "misting" a very thin amount of paint. I am sure that I could get very good results with better paint..... but I am going to try the Apple Barrel and see what happens. I will not use the 70% alcohol for this weathering of rolling stock. I found a great reducer recipe online that worked very well with the Apple Barrel paints when I did my structures. I also have a good recipe for air brush cleaner if anyone needs it.

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