airbrush "spitting"

[tmathew]

I keep having this problem with my Aztek A470, which always seems to "spit" out splotches of paint and then spray smoothly for a while, then do it again. I have thinned the paint to about milk-like consistency, and am spraying at about 14-18 psi with moistures trap and regulator. Is this a problem with the airbrush itself ?(compressor is brand new, and this happened with my old compressor as well)

[doraemon]

it seems that your airbrush is either blocked or wrong, this happens sometimes when you use it for a long time, the paint gets dry on the way out inside the airbrush if you use it too much in a row, but... if you get this from the beggining.... dunno

[raab]

i think that when you are cleaning it you arnt doing a good enough job. some times the paint can block the passage and trowing out some bigger peices of paint. either this or you dont have much psi goin to the airbrush.

[minniebanister]

Make sure the airbrush is absolutely, utterly, undeniably clean! I use acrylic paint and found that I can't even let the airbrush sit for 20 minutes without it spitting out globs of paint when I start again. Now, after spraying a coat, I run water/cleaner through the brush for 30 seconds before putting it down to wait 20 minutes to do the next coat. Then at the end of the painting session, I dismantle the brush and clean it thoroughly. (I have a Paasche VL double-action and I love it).

[lotus_man]

My A470s occasionally do this if the paint is too thick or the head isn't clean enough.

The other resaon (and only my 470s do this) is that paint can build up on the end of the tip in a blob, and then shoot off. Tends to be if I've got to much paint coimng out with not enough air. If this is the problem you could try adjusting the roller to flow less paint, or keep a rag on hand to stop the build up. I find laquers are worst for this, I think because they flas very fast...

[Guiddy]

I'd say the paint is still too thick! Go too watery and then work your way back from there!

[shieldwulf]

The needle may bent and has to be replaced even though it still appears straight to the eye. Roll it on a flat piece of glass to check.

[fredo]

I think this can also happen if the paint contains solid particles. Is your paint new from a new bottle ?
Maybe try to filter it.

[mike@af]

Strain the paint then Thin the paint a little thinner than milk

If that doesnt work then spray a bottle of thinner through it.

If neither of those work, turn your pressure up. Also, use the same thinner paint. I airbrush anywhere between 18PSI-38PSI.

That should do it.