I know that Golden makes an airbrush thinner/medium for their acrylics:
(second to last paragraph)
http://www.goldenpaints.com/products/medsadds/mediums/index.php
Those are designed for use with the Golden Fluid Acrylics (I highly recommend). I don’t know how well they’d work with other brands.
I think how they handle depends on your airbrush too. I’ve heard some folks on here say that they clogged their airbrush up solid right away, while some have been airbrushing forever without a problem.
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