What ratio is best for Testors Primer & paint thinner for airbrushing?

Depending on how thin the primer is I would start at 2:1 (2 parts paint to 1 part thinner) as that is my normal ratio for most colors.

Is that thinner compatible with that primer? It sounds odd to still be tacky even after 48 hours.

 

I concur with Mike. You didn't use enamel primer and acylic thinner or vice-versa? - You would know straight away if you used the incorrect thinner as the two would refuse to mix and would separate in sticky lumps.

I used Testors Airbrush Thinner (1789).  I think you are right though. I should be using a higher ratio.

 I 'm kicking myself now because I looked on the back of the bottle's directions and although it does say "For enamel paint only"; however, it instructs that for flat colors, the suggested ratio is 3 parts paint to 1 part thinner.  

 For me to use 1:1, I have way too much thinner in my mix and no wonder why it's not drying.  I'm lucky I practiced on scrap plastic and not my real model.  

 

mrclean08 wrote:

I'm lucky I practiced on scrap plastic and not my real model.

That's always the wisest way to do it!