First things firts, what paint are you spraying and most important, what thinner are you using.
what spray gun are you using and how much airpressure?
these things all affect the results when you are spraying so they are important. but in the interest of giving you a direction to look you may try some of these things,,
You could try narrowing the fan control on your spray gun this will put out more material in a smaller area thus keeping it wetter on the surface allowing it to flow out better. try reducing your paint a bit more, maybe another ten percent or so. Try a slower thinner. depending on what pressure you are using, try a lower pressure. You mention you had the same problem with the chipmunk and I assume it was not quite as hot when you painted it. This leads me to feel that perhaps your technique or material is not quite right.
Bottom line, when you get orange peel what is happening is that the material is not getting to the surface with enough solvent remaining to allow it to flow, or there is not enough material getting to the surface to begin with. as long as you are through all the color and spraying clear, you could sand the clear with 600 on a soft block, then reaply more clear with slower reducer, less air, gun closer to the surface, move the gun slower or add more solvent to the clear before you spray.
standard disclaimer, ALWAYS use the thinner designed by the paint manufacture for the paint you are spraying. I know lots of people say you CAN do this or that, and they are right, sometimes it will work, but the one time it doesnt you will hate them, the paint, the plane, and yourself..!!!