Acrylic Paint

[Showme]

  What is best to thin acrylic paint with? I have been experimenting with the Hobby Lobby cheap acrylics on plastic buildings and they have been turning out good, but some colors seem to not lay down right when thinned with water. I have heard of using Windex but haven't tried it yet. Opinions?

Bob

[Philip H]

Cheap auto washer fluid seems to work better then windex - though @peteski will tell you that since the main ingredient in washer fluid is alcohol you should just use that. You probably also need to ensure proper mixing of your paint, and even straining it through cheese cloth or paper coffee filters to remove chunks.

[peteski]

Cheap auto washer fluid seems to work better then windex - though @peteski will tell you that since the main ingredient in washer fluid is alcohol you should just use that. You probably also need to ensure proper mixing of your paint, and even straining it through cheese cloth or paper coffee filters to remove chunks.

Yes, it is (IIRC) methyl alcohol.  But there are many different formulation of water-based acrylic paints. Some will actually curdle when mixed with alcohol.  In some instances plain (distilled) water is the best solvent. Other paints are compatible with ammonia-based thinners.

[bman]

When using acrylics, I always use distilled water to thin paints from various mfg's.  I've noticed I've had to adjust pressure sometimes with the same paint mfg but different colors.  I've never sat down and thought it out.  Could it be something with pigments used?  I've used dollar store window cleaner to clean up before, but never to thin paint.  Not to hijack this thread, what's the benefit of using alcohol?

[Santa Fe Guy]

Well after years of air brushing with various brands of paint I have finally come to the realization to use the manufactures recommended product. I have used alcohol and it curdled my good bottle of paint. If I am using Tamiya I use their thinners, Vallejo then use theirs too and so on.
Rod.

[peteski]

Not to hijack this thread, what's the benefit of using alcohol?

Not really sure. Maybe it breaks up the surface tension of the paint?  But like I said, it can actually ruin certain brands of paint.

I know that certain water-based acrylics (like Tamiya) use isopropyl alcohol in their thinner (and as the solvent in the paint).  So it makes sense to use that type of alcohol for that specific paint.

[loyalton]

Depends on how you're painting. Airbrushing certainly needs something to reduce surface tension. 


To add to peteski's post, 70% isopropyl (or even less i.e., diluted) (not 90%) works with Tamiya. It works with Liquitex tube paint (art store). It worked with old Polly Scale. Those who used the Polly scale thinner with Polly Scale found it often worked badly.

[peteski]

Then there was the old Polly-S paint (before Polly Scale). Polly S was happiest with plain water as thinner.

[wcfn100]

Then there was the old Polly-S paint (before Polly Scale). Polly S was happiest with plain distilled water as thinner.

ftfy.

Jason

[nickelplate759]

Interestingly, I found that the Poly S thinner would curdle Poly Scale paint!

George

[peteski]

Interestingly, I found that the Poly S thinner would curdle Poly Scale paint!

George

Polly-S and Polly Scale had totally different formulation.

[jmarley76]

I usually stick with tap water for tubes of acrylic such as Liquitex, Golden, or any of those ilk. For acrylic models paints, I use the Tamayia thinner or isopropyl alcohol (70% or 90%). Distilled water has had the impurities filtered out, but I have never found this to have an impact on the paint, IMO.

[Showme]

  Thanks for the replies. I will give the distilled water a try. Alcohol did just what some of you were saying, curdling the paint. I was using regular tap water, and never thought about what was in it that might be causing some of my problems.

Bob

[peteski]

  Thanks for the replies. I will give the distilled water a try. Alcohol did just what some of you were saying, curdling the paint. I was using regular tap water, and never thought about what was in it that might be causing some of my problems.

Bob

I don't think that distilled water will make a difference if tap water wasn't doing the job.  There aren't that many impurities in the tap water. But distilled water is sheap enough that it is worth a try.  You coudl also try some ammonia-based liquid (like Windex) to see if it works.  Art supply stores also sell a liquid which improves flow of water-based acrylic paints (I don't recall the name right now) - you might try that.

Personally I still use the old-fashion smelly paints for majority of my hobby painting. I mostly use the water-based paints for things like weathering and some hand-brushed detail painting.

[muktown128]

The alcohol will reduce the surface tension of the paint.  This should allow it to flow out and avoid thick areas better around corners and edges (detail areas like molded ladders, mesh screens, etc.).  Lower surface tension should also help the paint wet out over dirty and contaminated surfaces.  However, good cleaning and surface prep should take care of those issues.

Scott