Painting Styrene (and getting the paint to stick)

[taholmes160]

Hey Everyone:

My adventures with the little station project continue.

Tonight I took my built and puttyed station out to the garage and set up my airbrush (which I am also really new at) and tried to paint it.  I using Valejjo paints and had to thin it a bit with water to get it to paint right, seems to paint ok, but the paint does not want to stick to the model.  Before I painted, I put on gloves, washed the model in hot soapy water, rinsed in clear water and then hit it with 91% rubbing alcohol, to make sure all the mold release and finger prints were off it.   other than my crummy technique, the paint seemed to lay down ok, but like i said, i can scratch it off with a fingernail, and it seems to not be a smooth film, but more "grainy" but from a distance, looks fine

any input, or suggestions for good airbrushing tutorials would be very appreciated

Thanks
TIM

[wazzou]

Prime it with cheap, like Walmart Gray Automotive Primer.
Several light coats are best.

[peteski]

Yeah, water-based acrylic paints do not adhere well to smooth plastic. That is because they don't have the "hot" organic solvent to slightly "bite" into the surface of plastic.   Priming with an organic-solvent-based primer (the stinky stuff) results in a rougher surface to which those water-based paints can adhere.

EDIT:  double thanks DKS!

[DKS]

to which those water-based pains can adhere to.

 

[Dave V]

I prime with a rattle can too, but depends on what I'm painting the styrene as.  If I'm going to make the styrene look like wood I go for the tans, grays for metal, and so on.  I found a good prime coat allows those craft acrylics to stick nicely.  In fact I use almost exclusively craft acrylics now for my railroad structures.

[thomasjmdavis]

I second or third or fourth the advice on priming- although I have found acrylic primers to be satisfactory on plastic (metal not so much). Humidity also makes a difference when painting with acrylics- if humidity is too low, the paint may be almost dry when it hits the surface- resulting in both a grainy coat, and poor adhesion. The other thing I have found with some acrylics (Model Master, Vallejo, Rapido, and to a lesser degree Modelflex)  is that both adhesion and surface hardness improve with time.  Although it may be dry to the touch and ready for a second coat in a half hour (an upside to acrylics), I try to let mine cure for 24 hours after the final coat, before handling.

Or decaling.  Especially that.  Decal solutions can cause clouding, or even lift the paint, if the acrylic has not cured thoroughly.

Of course, your mileage may vary.

[peteski]

You caught my typo. Thanks for your proofreading my post

[Santa Fe Guy]

I would not thin Vallejo with water. Use their paint thinners. I also would spray an undercoat first. My preference is Tamiya surface primer in a can. Goes on nice and thin, dries fast in the right conditions and will accept most acrylic paints well.
Rod.

[DKS]

You caught my typo. Thanks for your proofreading my post

to which those water-based paints can adhere to

Still missed one. Hint: too many tos.

[bman]

I also use Tamiya's Surface Primer. I'm going to guess you are using Vallejo Model Color paint since you mentioned having to thin it.  I use Model Color paint but usually with a brush on 28mm gaming figures. I've never tried to airbrush them. Have you tried the Model Air and Game Air lines from Vallejo?  They are ready to air brush straight from the little squeeze bottle. My son uses these more than I do for painting his terrain and buildings for table top miniatures games. But when I've used them I've been happy with the results. Also, Vallejo now has a line of primers that a friend in the local figures painting group gave me a bottle to try.  I tried it on an old loco shell I stripped and was impressed with how well it went through my airbrush and went down on the model.  I guess it's even better with a couple of drops of  flow aid in the paint cup. I think that's by Liquitex? I have to ask as I forget. So I'll be trying that next when my pieces parts come in. Since your using Vallejo paint I thought I'd toss that out there.

[taholmes160]

WOW- - great stuff there -- thanks tons

I goofed up and got model color rather than model air, but just purchased a bottle of model air today, so I'll try it.

Does anyone have any recommendations for thinning the model color?  ive got a couple bottles that I would hate to waste

TIM

[JanesCustomTrain]

Does anyone have any recommendations for thinning the model color?  ive got a couple bottles that I would hate to waste

TIM

This

https://www.amazon.com/Vallejo-Airbrush-Thinner-200ml-Paint/dp/B002X6DTHK

Jane

[peteski]

My recommendation is to stick wit thinner specifically made for the brand and type of paint.  People give all sorts of recommendations of what to use (even things like windshield washer fluid, etc.) but with so many different types of water-based acrylics out there (with different chemical formulas), I don't believe there is such a thing as universal thinner. Distilled water is probably closest to being universal, but even then, it might not work as well as a dedicated thinner.

This is quite different from the old-fashion organic solvent (stinky) paints where most thinners are compatible with most lacquers and enamels.