Airbrush Paint bubbling.....

[Dax]

My airbrush (Iwata Eclipse HP-BCS) is bubbling the paint jar paint, a back flow into the jar. Normally, I've found this to be a blockage to the nozzle or the head cap not being tightened enough, but I've just replaced the needle cap, nozzle cap and head cap (I cleaned them all just to be sure) and its still doing it. It's also only during it with for the first 1/4, maybe half, or so of the the paint flow throw pullback.

I cleaned the body as thoroughly as I could (multiple times) retorqued all the caps (again, multiple times) and it is still ding it. :)

Ideas?

[Don Wheeler]

This can happen if there is an air leak into the paint path where the nozzle seats against the body of the airbrush. Make sure these surfaces are clean and smooth. If they are, try a little bees wax here. Have a look at the third picture down and this page.

Don

[toadwbg]

I had this problem recently, solution was to tighten the front assembly to the body better sealing here. Note their is an o-ring at this joint and it can become damaged over time and spills of paint drying it out. You need to replace it eventually.

[denstore]

It could be a broken nozzle as well. Sometimes the crack is so small that it can't be seen, but it is noticed from air coming through the cup.

[MikeC]

I recently had this mysterious bubbling on my HP-CS with a brand new nozzle and needle, having replaced the old one. Eventually a (very) close examination of the nozzle revealed it was the tiniest fraction too long. So I replaced it (I always carry a stock of two or three spare needles and nozzles - never know when you'll need one in a hurry) and everything was fine again except that I have paid good money for a duff nozzle. C'est la vie!