Alcohol as a cleaner/thinner for acrylics

Wondering if there are any informed thoughts out there on the use of isopropanol vs ethanol with acrylics, particularly airbrush cleaning.

For those of us living in the US, Isopropanol (aka, rubbing alcohol) is what we commonly find at the drugstore, and it is pretty much unbeatable for stripping acrylic paint. Having relocated to Japan, I have discovered that drugstores here don’t carry Isopropanol, but rather either straight (~76%) ethanol for medicinal use or a blend of ethanol, methanol and isopropanol for fuel. What I am unsure of is whether the ethanol or ethanol blends would be too aggressive for use in an airbrush. Anyone have any thoughts?

:beer:

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Definitely not for Vallejo,turns it into a gummy mess.

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I typically use vallejo thinner with AV paints, but I’ve cleaned with rubbing alcohol without any problems. It’s great for thinning Tamiya because it gives you a consistent dead flat finish.

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I know that an isopropyl \ methanol \ glycol mix (windshield washer fluid) works great for thinning Tamiya paints, and cleaning airbrushes, so go ahead and give the ethanol mix a try. It’s worth a shot.

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For stripping acrylic, the alcohols you mention work well. Ethanol at 76% percent is also 24% water, and probably tap water at that. I recommend you avoid that. As for the fuel mixture, as long as those are the only components, it should be safe for the airbrush, but don’t let any of it sit in the airbrush between uses. Make sure it all gets blown out.

There is another consideration: methanol is poisonous, more so than isopropanol. If you are using these for cleaning or stripping, make sure you have adequate ventilation, i.e., a spray booth vented to the outside. A filter type booth is not adequate for those solvents.

Because I use Vallejo almost exclusively, I can’t speak to solvent compatibility with other paints other than Tamiya. Tamiya is compatible with isopropanol, but concentrated ethanol and methanol tend to cause it to gum up, though they can be used for stripping.

I’ve found it is economical to use Vallejo thinner and airbrush cleaner with Vallejo paints. One can use distilled water with a surfactant cleaner like Formula 409 to clean them, but at least with my Grex and T&C airbrushes, it takes surprisingly little of the Vallejo cleaner.

Do you have some old, empty paint bottles? You can use them to determine paint/solvent compatibility: Fill one half full with the solvent in question. Add paint drop-wise and observe its behavior. If a drop of paint instantly spreads out, mixing with the solvent, the solvent can at least be used to clean the airbrush or strip the paint. If the paint droplet stays together, try to stir it in. If it readily dissolves, the same result applies, at least marginally. If it turns into a globby mess, don’t use it with that paint for anything. For the ones that look promising, add more paint, at least a quarter of the solvent volume.In all cases except the globs, let the mixture stand at least overnight (several days is better). Then see stir it up, let it settle out again, and finally drain the excess solvent and let the paint dry, or apply the paint to a clean piece of scrap styrene. Once dry, check the adhesion. Fair adhesion or better means the solvent works well with that paint.

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Mr. Aqueous also thins and sprays just fine with isopropanol. However, Italeri acrylic paint will be thinned by it, but will start forming short strands within a few minutes that you don’t want to be spraying at your model.

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The only paints of which I’m aware that are fully compatible with alcohols are Tamiya and one of the Gunze lines.

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One time I also bought 95% alcohol to give a try diluting acrylics but never did so. I do use thinner with my paints for airbrushing and one 400ml bottle of Gunze thinner lasts at least two years, sometimes 3-4. I found it ridiculous saving some little or no money per airbrushing sessions on using alcohol and other mixtures i.s.o. the paint manufacturer’s own thinner, when I easily spend 200+ USD on the kit and aftermarket goodies. Such saving is just not right for me.

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That would be the Mr. Aqueous paint I mentioned :slight_smile: Mr. Hobby is lacquer, Mr. Aqueous, despite the name, is alcohol-based.

Revell Aqua-Color can also be thinned with isopropanol, but I’ve not tried spraying it with that — only reconstituted almost–dried-out paint in the pot (because those little square plastic pots are only slightly more airtight than a sieve).

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Guys,
Those are all great responses, and just the kind of info for which I was looking!

:beer:

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Use that high-test isopropyl alcohol for cleaning the airbrush. If any paint’s thinning ratio with their proprietary thinner is reasonable, use the proprietary thinner. Every minute spent researching solvent compatibility is lost to building! (Yeah, I do it, but it’s sort of ingrained, having once worked in that industry. :disguised_face:

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Revell, the giant of the 1950s, has fallen far.

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Revell’s contact cement much to my surprise is actually good.

Likewise, Revell’s enamel paints (when reduced with Mr.Color Leveling Thinner).

Like they say even a blind hog (Revell) occasionally stumbles over an acorn.

Long live Revell-a-gram…

:wink:

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I use alcohol to thin Tamiya paints for airbrushing. Around 1:1

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91% Isopropyl alcohol is my go-to for cleaning Tamiya and AK Interactive Acrylics. But for Vallejo, I use their thinner.

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The paint itself is quite good: it paints easily, it covers well, you can drybrush with it, it cleans up with water, it thins well for spraying with just water too – I would recommend it. The problem is the pots it comes in:


They are all plastic, with an odd, wedge-shaped top/cap/lid you have to twist off (the label explains this, but I’ve read people complain they can’t work it out), but that works well enough. The problem is that the seal between the circular part inside the cap and the circular inner bit that actually holds the paint, is not very good. At least not once the pot has been open and used for a while — even if I clean the paint from both after use, within a few years all that’s left inside is a thick blob of hardened paint.

These pots are just as bad as Games Workshop paint pots of about 15 years ago (I haven’t bought any of their paints in that long, so I don’t know if they’ve gotten better :slight_smile:_)

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:rofl: I grew up with Airfix and Revell as my only choice it wasn’t until online shopping allowed exposure to other companies. I really like using Tamiya’s extra thin and Vallejo products but I still buy Revell kits and glues.

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As for the paint, sounds like a good product until the marketing department got a hold of it. Model paints should have a very long shelf life, and packaging is a big part of that. When you consider the actual price per gallon of model paints, anything I can’t keep on the shelf, partially used, for at least ten years is not worth a penny. That’s why I like Tamiya—best packaging I’ve seen. (And as a former paint technologist, I’ve seen a lot of paint.)

I’m a bit concerned with Vallejo changing the material of their bottles. I hope it’s an improvement. The old ones performed well: I have some over ten years old, partially used and still perfectly fine.

The quality of Revel kits got so bad I’m surprised they are still in business. I grew up with their kits, and I remember they were pretty good. Even when I was in grad school the quality was still there, but some time after that it took a nose dive.

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Probably, yes. “We need to have bottles that stand out from the competition!” Or maybe it was the engineers: “Square bottles are easier to stack, and we can make the lid attach to the side as a handy palette!” but then forgot the most important function of paint containers: keeping the paint fresh.

Except they have given me a callus on the side of my left index finger, from trying to open too many caps that have been glued to the bottle by paint in the threads :frowning: Though the Mr. Aqueous bottles seem to be even worse: smaller and paint that seems to glue even better than Tamiya acrylics :slight_smile:

Of Revell USA, I’d say. Revell Germany kits were generally better than those from the American branch, which was very noticeable even when I didn’t know yet that there were two sides to the company. Seemingly at random, some kits were of pretty good quality while others were very poor. Later on, I learned why.

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Care to enlighten me?

For quite a while, I had very little time to build. But I kept acquiring kits. I found a number of Revell and Monogram kits that I had built years ago, and bought them. Recently, I opened and started working on several of them. The fit was so bad in some cases they could not be assembled. I was very disappointed. I hope I do not find the same thing with some of the “newer” ones (from the ~1980s).

As for Tamiya paint jars: I always wipe the bottle rim and inside 1/4 inch free of paint, and run a cotton swab around the inside of the cap where the seal is recessed. If you stilll have trouble, smear a light coat of food-grade silicone lubricant on the bottle theads. Won’t hurt the paint unless you get it inside the jar.

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