My place is on the mountains around Rio de Janeiro

Its hot like hell (the hottest summer yet) and relative humidity is quite low (varies between 30 and 40%)

I'm using 1 part paint mixed with 3 parts iso-propyl alcohol. Pressure between 10 and 15 psi.

The result is a surface looking like a grainy sandpaper

I understand that the paint is almost dry before reaching the model surfaces.

I don't use the Tamiya X-20a because it is very hard to find here, and importing regulations makes it more difficult to purchase from other countries.

What kind of retardant or solvent can I use to improve my airbrush painting?

Any help will be appreciated.

Cheers,

Flores

That seems pretty high to me.I use about 60-40 paint to thinner or Iso

Hi Flores,

Move the airbrush closer, drop the pressure a little bit and find the distance ratio that works for you so the paint hits wet, then dries. Iso Alcohol dries so fast it makes the paint less flexible in this regards, so you need to fine tune your distance and pressure ratio. Maybe adjust your thinner ratio during your tests as well. Test spray, re-test, and re-test again until you can replicate the correct results. Then practice some more, and then spray your model.

Classic issue with airbrushing acrylics in general, not just Tamiya. You are spraying too far away and too high pressure and this makes the paint dry before it hits the surface.

However, there is a possible fix if your model is already painted and has this texture. It happened to me when I was using the CM technique because of the angle of airbrush and trying create the subtle gradations. Spray straight Lacquer thinner neat onto the pebbly paint surface. Spray enough so it is rather wet, not dripping wet, but glossy wet, it will look like a gloss coat. Let it dry, the lacquer thinner will dissolve those pebbles and level the surface back out. The paint will look a bit shinier than before, but it removes the majority of the error and lets you continue working on it.

I've found long in the past,that Tamiya paints don't thin very well without Tamiya thinner.
Don't know they did it ,but as soon as I started using it I had no problems with an airbrush.

Tom

I'm in Egypt where it's very hot also... after having a lot of problems with my AB, I finally got it to work right. I'm getting great results spraying Tamiya paints thinned down 40/60 with alcohol mixed with some Windex and a couple of drops of paint retarder. It seems to work well for me

Hisham

You could try adding a few drops of water as a retarder.

Alternatively, you could move from straight isopropyl alcohol (IPA) as a reducer to a lacquer thinner or a mix of lacquer thinner and IPA.

(Note: Lacquer thinner - sometimes called cellulose thinner - NOT mineral spirits or white spirits.)

The lacquer thinner will likely dry somewhat slower than the alcohol, but it will work well with the Tamiya paints.

I use a mixture of about 3:2 lacquer thinner and Tamiya X-20A (which is, as you know, mostly just IPA), and the use that to thin my Tamiya paints. In my painting humidity and temperature, this has good spraying and drying properties.

HTH,

I had the same problem. I started using lacquer thinner, mixed 1:1. I reduced my psi to ~25 and hold the airbrush about 2.5"(6cm) from the model, using slow passes. The main problem I believe you have is using alcohol. If you can't get Tamiya thinner, try generic lacquer thinner.

I thin my Tamiya paints with good old car windscreen wash. Works great for me and alot cheaper than thinners.

Pete

To all of you people above (Tojo72, rinaldi119, parrot (tom), Hisham, SdAufKla (Mike Roof), retiredyank (matt nethery), noddy927 (Peter Sutherland-Findler);

I'm greatful to the help you gave me based on your experience, that I'm sure will turn my acrylic's airbrushing into a pleasant part of this hobby.

Cheers,
Flores