What to thin Model Masters Acrylics with

Well, MM acrylic thinner works. I have made a home brew thinner using half distilled water and half 70% Iso, and a few drops of liquitex retarder. It seems to make it go down more translucent and makes the paint a bit more durable. 

I use isopropyl alcohol 91%.  In the airbrush I add drops until the paint reaches a viscosity akin to water while stirring with a toothpick.  Once all done I clean with acetone nail polish remover and it works like a champ removing any need for elbow grease. 

I use MM's brand universal acrylic thinner. I got tired of trying to figure out my own, 'cheaper' alternatives. A $7.50 bottle (really only around $4.50 after a Hobby Lobby coupon) has lasted me a couple years and probably at least ten models. This is one area where I'll actually buy the brand name stuff, which is not usually the case for me.

Chris

+ 1 with dirtpitt77. That's what I use with much success.

I also use the MM brand universal acrylic thinner.  It doesnt take a lot of it to thin it down and it seems to last a long time.

A tip I learned from CallSignOwl is to thin with Future. I've used that method a few time in both brush and spray applications, and found it works well. I've yet to try the MM thinner.

Mike