i use Tamiya paints a lot too, and i have to agree w/ Merlin -
i gotta thin 'em!
anywhere from 3:1 to 1:1 (paint:thinner) depending on the color.
i am running an Aztek and 20 psi.
(yes, i am one of the 7 people who are not complaining about the Aztek!)
i use Tamiya thinner from the 250 ml bottle.
i got them to stock it at my LHS.
the bottle costs only abt twice what the 50ml jar (20A ?) costs, but is 5 times as big.
i am too lazy or timid to make my own thinner.
i KNOW Tamiya's thinner will work and it is not prohibitively expensive.
ed.