Airbrushing: Acrylic vs Enamel?

Model Railroader General Discussion (Model Railroader)
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I’m sure this topic has been rehashed to death, but to be honest a few searches didn’t yield the kind of information I’m looking for.

I’m going to be buying my first airbrush soon, and I would like to know what folks recommend regarding the type of paints I should start with. My understanding is acrylics are easier to clean up, safer, and dry faster allowing quicker layering of colors. On the other hand I’ve heard enamels give better results, are easier to airbrush, and give a tougher finish. Additionally enamels can generally be sprayed without primer while you usually need to prime first with acrylics.

Does it make a difference if I’m asking for weathering or painting? I plan to use the airbrush primarily for weathering, but I also have a few unpainted die cast, brass, and resin models I would like to paint. When weathering how long will I need to wait before changing colors or applying another layer with enamels? What about wait time between coats on a complete paint job?

If I go with enamels I will almost certainly use Scalecoat as I live less than an hour’s drive from their physical store. If I choose acrylics I’m less certain, though I have heard very good things about Testors. Please share your recommendations and personal preferences.

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VGN800,

What works best for you depends on your airbrushing skill set. Like you, I recently started using an airbrush.

I use rattle can spray paint for most of my models. The airbrush in my case is used to weather my models. Acrylics in my humble opinion are great for this purpose.

Enamels on the other hand…

Still not comfortable trying to paint a locomotive yet. Experimentation will yeild better results through time. Got so old Tyco cars that will be test subjects.

Dunno, why I waited this long to get on the airbrush train .

Patrick

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[#welcome] to the Model Railroader forums. Your first few posts will be delayed by the moderators, but that will end soon enough. Please be patient and stick around and join the crowd.

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I only use solvent based paints in my airbrushes. I like the glossy finishes I can get, they are easy to clean up, I can get the mix just right, and I am happy with the results.

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I also learned with solvent based paints.

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People who learned with water soluable paints also can get the results they expect and are happy with. I do not like the results I get with water soluable paints.

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Either way, it will take practice, but it is not too hard to learn.

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Have fun!

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-Kevin

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The down side to solvent based paints are the hazardous vapors. Basically a paint booth is necessary to vent the harmful vapors assuming you can vent enough away to remove the risk of breathing them. I am 40 Hr OSHA hazardous waste operations and emergency response trained have a respect for the harmful nature of the constituents in the solvents, such as toluene, xylenes and other petroleum based compounds.

A paint booth can remove a lot of those vapors but all? A proprerly fitted full faced respirator with the correct cartridges is probably the best way to ensure you won’t be breathing the harmful vapors.

Here is a link to the MSDS for Toluene for example:

http://www.sciencelab.com/msds.php?msdsId=9927301

Prehaps a good compromise would be a good vented paint booth and a half face respirator with a cartridge that is suitable specifically for the paint solvents.

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What RioGrande5761 says it dead on. I spent years doing a lot of airbrushing with the old Floquil back in the 60’s and 70’s. No ventilation, no paint booth, not anything except my lungs sucking the vapors in.

Now, years later, I have intense allergies to all paint type solvents. I have no choice but to use acrylics even with a paint booth. Probably other damage also that I don’t know about, simply blaming it on old age.

Do yourself a big favor and don’t use solvent based paints without the best protection you can. That includes a good paint booth vented outside.

Learn from dummies like me.

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Used both successfully (more or less) and i think I preffer solvent based more. Can’t explain why, somehow I just get better results with it, your experience may be different.

Good points on safety. If I might add that booth and mask is good idea even for acrylics - the aerosol is not good for you even without vapors. Plus booth can be helpful for organizing your desk and it doesn’t have to take a lot of space . Below is my very compact desktop one.

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The issues are pointed out above. I had only used my airbrush for one project before this year but advanced to “intermediate” skier (airbrusher) this year. Some related comments…

I am emphasizing acrylics for a couple of reasons. One is minimizing exposure to hydrocarbon solvents, including on cleanup. Another is that my inexpensive (but adequate), externally vented paint booth may not be strictly compliant regarding flammability concerns because of the motor design. Whether the relatively small flow of airbrush solvent type paint mixture and/or cleaning solvents would reach flammable mixture levels given the booth airflow is perhaps doubtful, but perhaps more likely with rattle can output. But I don’t have to worry.

IMG_9120 (2) by Paul Ahrens, on Flickr

A big initial issue for me as I tried some projects this year was cleanup. Experienced folks, with both types, have learned & optimized what works for them w/o excessive time and effort but for me it was quite a learning experience on the acrylics, primarily using Testors Model Master and/or Badger Modelflex I had acquired. I had a heck of a time cleaning the airbrush tip guard and even the paint cup, even though acrylic.

I also had trouble getting a nice gloss clear coat (before decals).

I researched lots of prior threads here and a fair number of YouTube videos and that got me over the hump. I was determined to find an acrylics process that worked out for me as my base approach. I focused on Testors Model Master and found success. Some examples:

  • On paint dilution, one video showed how different thinners can make a significant difference in the results. So, best to start out with the Manufacturer’s thinner, e
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[#welcome] to the Model Railroader Forums, VGN800!

I started painting, back in the mid-'50s, using a brush and Floquil paints, and have used most brands of model paint since then, both with brush and airbrush.

In my opinion, the hands-down best-of-the-lot was Floquil’s PollyScale - not predecessor Polly-S and not the more recent versions of PollyScale, and definitely not the final ready-to-airbrush version (useless for brush work).

It came in a wide range of colours, was fast drying, and as durable as any lacquers or enamels. It was very disappointing when Testors opted to discontinue it, in favour of their ModelMasters line - not a bad paint, but definitely inferior to Pollyscale in ease of application, versatility, durability, and shelf-life.

I still have a fairly good supply of Pollyscale in most of the colours I use, and a lot of other brands specific to certain end uses or particular projects, but have also acquired a fair amount of Scalecoat as the eventual replacement for Pollyscale.

I’m not too enamoured of its slower drying times, though, as it often means that painting sessions that formerly allowed me to do up to four dozen freight cars in a session with PollyScale, and then place the dry-to-the touch cars into their respective boxes, in order to carry them (in a larger box) from the paint shop in my detached garage the hundred feet-or-so back to the house, are no longer possible. There’s no way to move that many items at one time if the paint is still wet…and may not allow easy handling for several days.

When I paint steam locomotives, I use four or five different colours (mostly various versions of “black”) and in most cases, apply them consecutively, using only hand-held cardstock masks at colour separations. With fast-drying PollyScale, this was, except for changing bottles on the airbrush, a non-stop operation. With slower-drying paints like Scalecoat, the same process takes days t

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Can you even get paints with these solvents in them anymore? I thought the EPA crackdown on these is why Floquil is no longer available.

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I use both Acrylic and Solvent based paint in my airbrush and both work very good. I normally use Solvent based paint (Tru-Color) when painting locomotives and passenger cars for durability and Acrylic (Crafters Acrylic) for freight rolling stock and structures. Weathering my freight cars takes care of any flaking caused by handling.

I thin the Solvent paint (TCP) with Acetone and the manufacturers recommended thinner for Acrylics. I’ve never had problems using either in my airbrushes, single or dual action. Prompt cleaning keeps the airbrushes working good.

Using ether type of paint I can switch colors on the fly without any problems. If I’m doing a lot of painting using several colors in one batch I have a five port manifold so that I can use multiple airbrushes and not have to swap paint bottles. My primary single action airbrush is the cheapo from Harbor Freight. I have five of the HF single action cheapos and they work as good as the higher priced models.
I normally use Testors Dullcote in the rattle can for sealing.

I add a little of 70% Alcohol in the Acrylic mix if I need super fast drying time when I’m switching colors.

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I use exclusively acrylic’s.

I still use a booth, and wear a mask, even with acrylic’s, as I have asthma.

I tried using rattle cans outside, but even that was not going to work out well enough.

Some tips with acrylic’s, they make a acrylic airbrush medium. What this is, is thin acrylic medium, that can be used in place of thinner. I mix this 50/50 with distilled water (bonus tip - never thin with drinking water or tap water!) to use as thinner instead of buying each brands own thinner.

Second bonus tip - Doing this allows you to custom mix with craft acrylics as well.

Clean up - I quickly spray a full cup through of drinking (tap) water, then will either, A: tear down and clean with a old toothbrush and a bucket with soapy water in it, or, if simply changing colors, B: spray some soapy water through, then continue using tap water until it sprays clear.

I also will, upon reassembly, use a product called “needle juice” on a lint free cloth to wipe down the enire airbrush body, cap, cup, needle, and trigger, before reassembling it.

Never had any issues with “stuck on” dried paint this way.

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Thank you to everyone for the detailed advice! Based on the fact that I will be painting indoors (albeit venting out a window) I think I will stick with acrylics to start with. I will probably use Testors Modelmaster paints as my jumping off point and see how it goes from there.

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Who or what is they?

Valejo seems to dry out in the airbrush faster than Model Master. I bought some retarder and it makes a small difference.

As soon as I finish shooting a color, flush the airbrush by shooting a mixture of water and alcohol. I will put a paper towel over the nose of the airbrush and backflush, then change the flush in the jar.

When it sprays clear, I am done cleaning. Every few months I may take the airbrush apart and clean it with laquer thinner. I am not really sure why laquer thinner cleans acrylic paint but accept it.

In my area, I can’t see any difference between tap water and distilled water.

I tried a HF airbrush when my Badger was in the shop for a lifetime warranty issue and I didn’t like it.

I prefer acrylics, because I don’t want the solvent exposure. I’ve had far too much exposure in my life and while I don’t have asthma, any number of pungent smells will start coughing fits.

I believe that today’s better than average train store, has a worse selection of paints than 30 years ago. As I go to various train stores, I buy what I need, something that is Tru scale, sometimes Scalecoat, Model Master or Valejo. I have never tired Tamiya

Use a respirator and a box or spray outside.

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Yes. Scalecoat, Testors, Model Master, Humbrol, Alclade (I probably spelled it wrong), and many more.

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I don’t think the EPA came after Floquil and left Rustoleum alone… that makes no sense.

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I think it is far more likely the Floquil line was outdated and not selling well.

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-Kevin

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Regardless of the type of paint I use in my airbrush, I always clean it with lacquer thinner only, and likewise for brushes (natural bristle).

Wayne

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Sorry, I know there are solvent based paints still available, I was referring specifically to toluene and xylene. Do any of these paints use either of these two solvents? Floquil contained both of them.

I know this is not correct. There was a major uproar when Floquil was removed from the market. People are still hoarding it today.

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Here’s one:

Here’s another:

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Scalecoat 1 and Humbrol enamel both use xylene. Alclad is a cellulose/laquer based paint were both is possible.

Another magazine published a guide with acrylic equivalents to Polly Scale paints and how to handle them some time ago: https://www.testors.com/~/media/DigitalEncyclopedia/Documents/Testors/ebook/MRH-Acrylic-painting-guide-post-Floquil-Portrait.ashx

It has been updated. You can find it on the magazine’s website.
Regards, Volker

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I have the MSDS info on Scalecoat, and Scalecoat I and Scalecoat II both use Naphtha and Xylene as their solvents, albeit in differing proportions.

I would recommend that if you’re spraying solvent-based paints, wear a two-stage respirator and spray either in a spray booth vented to the outdoors or spray outdoors (and wear the respirator).

EPA regulations notwithstanding, the amount of harmful chemicals released by airbrushing modellers is miniscule, but if you’re one of those airbrushers, do yourself a favour and wear a two stage respirator - that miniscule amount going directly into your lungs can prove dangerous with repeated exposure.

Wayne

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Having developed asthma I won’t use solvent based paints anymore. Albeit the paints weren’t the cause.
Regards, Volker