airbrush spitting

While painting a camo pattern with red brown Tamiya Acrylics when i would just barely pull back to let a tiny amount of paint flow i would get blobs spitting onto my model. I thinned the paint 50/50 with alcohol and the spitting stopped when I pulled back further. I have no regulator (its on the way) so I dont know what pressure im spreaying at. Its a Badger Cyclone II compressor. Im guessing its somewhere around 30 psi but i could be way off.
What can i do to prevent this. I was using a #1 needle and tip? Thanks

Unless the tank is painted on the inside, you should install a moisture trap _between_ the compressor and the tank, or water wil condense inside the tank and corrode it.
And a corroded tank with 90 PSI inside is definitely not something you want to have hanging around...

I think you are missing the point here. If you have a full size compressor already - use it ! Just get a pressure regulator to reduce 300psi to whatever you will be airbrushing with (5-30psi) and put the moisture trap on the low pressure side. I have all my stuff hooked up using the quick connect couplings. So it is all modular. I can shuffle my regulator and moisture trap as I see fit.

And I'm sure they make moisture traps for 300 psi too.

But as long as you have a steady high pressure available - you are golden !
And I'm sure your 300 psi compressor has a storage tank - so you are all set.

Where can you purchase c02 bottles? Do they require a special fitting to attach the regulator?

I had problems with Tamiya acrylics, getting a rough, sort of gritty finish.
(This is a milder form of spitting.) Steve Zaloga suggested in one of his seminars that I thin with clear Windex, and add "more" thinner rather than
"less". I was skeptical and did not try this for about a year, but finally broke down and did it. Pastafazool - it worked! You'll have to play with a ratio that seems right (maybe 1 part Windex to 4 parts paint to start), but dang it, it works.

Another good reason to use CO2 instead of air........... No moisture trap required and no compressor to run.

I hope this helps.

The best airbrush air supply I ever had was a hand pumped insecticide tank in my room in the <email> Sta, Guam in 1969. I was using a Thayer &amp; Chandler Airbrush ( very much like a Badger 200).

That said, get a stand alone tank (I got mine at a Sears &amp; Roebucks)
rated at 125 psi. Feed it with your compressor via a hose. Set the regulator on the compressor at 90 psi (keeps the tank from going
BOOM). Put a second regulator and moisture trap on the tank out to your airbrush and set it to the pressure you want to spray the paint (usually 10 to 35 psi). Sorry about the English units but Americans are not smart enough for the metric system. All we know is how to is blow **** up.

This does away with air pulsations and pressure drops (unless your painting a full sized VOLVO.

You get a smooth, constant pressure, dry air supply. Then practice on some really cheap models till you get the feel for the brush you are using. Cheap **** Box Cars are a really good 3-D cheap way to avoid wrecking an expensive or over priced kit.

2"x2"x10" (50.8mm x 50.8 mm x 254.00mm, I majored in Physics )
blocks of wood, primed with a good automotive primer are even cheaper.

You want a constant pressure, dry air going through your air brush for the duration of the paint job. This is the key to getting the paint on the model without it looking like the paint was sneezed out of the air brush. Make sure your brush is clean, clean, clean. Don't spay during high humidity (rain or nearly rain).

I hope some of this helps.

How do I fill a tank to 90 psi when my current airbrush compressor only pumps at around 30? I have a full size compressor for tools etc. but I'm not aware of any moisture traps that will fit on the full size 300 psi air hoses. Do they exist?

Thanks for your help everyone! I ended up getting a small 5 gal tank to fill up with my large compressor in my garage. Its much eaiser to use inside (which is where i plan on using it) Im gonna throw a regulator on it and I should be good to go. Thanks again.

Most of the "spitting" in my experience is from the water that condenses from your air source as the air goes from the high pressure tank through your air brush into the atmosphere, pulling the paint along with it. As the air moves from a high pressure source to a low pressure area, it cools and causes the humidity in your air source to condense and blow all over your model. When I started using an air brush many years ago, I used the "canned air" that came with my air brush. The spitting was really bad but I was able to minimize the problem by putting the can into a bucket of water (maitaining its temperature) as I sprayed. I have never used a compressor for air brushing but am very happy using compressed CO2 with a regulator.
The CO2 can be refilled anywhere they service fire extinguishers or pressure tanks for beer taps. The regulator is a little expensive, but the control and modeling results are surely worth it.