Why is my airbrush spluttering/fading?

[Captain Mark]

Hi guys,

I've recently starting practising shooting Tamiya TS-20 (Metallic Green) from my airbrush, in anticipation of getting my Fujimi Mini kit.

I've found, however, that my airbrush is spluttering the paint out, sort of. The paint sprays for a moment, then slowly tappers off and it's just air. A few seconds later a spot of green may come back, only to stop again, and so on. I've used both Tamiya laqcuer thinner and high grade automotive thinner, but had the same effect. Straight thinners doesn't splutter as the thinned paint does (I normally thin the paint around 1:1 to 1:2, paint:thinner).

I tried spraying Tamiya acrylic gold, same problem but less pronounced. I've also pulled my airbrush (Iwata Revolution CR gravity feed) apart as much as I can and cleaned it thoroughly, but there's some areas I can't get into to clean very well - could this be the problem?

Any input would be great here, as I'm not sure what else to try. Has anyone experienced the same, or have any advice on how to stop this problem?

Cheers all.

M

[speener]

Make sure you check all the seals and that you put your airbriush back together properly. Also, after you clean the air brush you should rinse it out with water (distilled) put some in the cup and spray it through to eliminate the residual small drops of cleaner left in the airbrush. And make sure your thinner matches the type of paint you are using. ie, acrylic thinner (Tamiya X A20, i think) for acrylic tamiya paint.

[stevenoble]

I sometimes have this problem and usually it's some dried paint in the tip that causes it.I bought a cleaning reamer which you put into the tip and this gently removes the dried paint.Sometimes I thin the paint more as well 1 part paint to 3 parts thinner on some occasions (about the consistency of milk) I've also started to filter the paint before it goes into the airbrush to remove any particles.

[Captain Mark]

Thanks guys, I'll give it all a try.

[bhop73]

Both paints you mentioned are metallic.. so i'm going to guess that it's a problem with the metallic flakes. I've noticed that metallics needed to be thinned a little more than solid colors when i've used them.

[MPWR]

The first thing I would check would be pressure. I spray laquers thinned 1:1-1:2 like you describe trough a gravity feed Badger at the lowest pressures I can- right around 15psi. But lower than that and it will splatter and do other nasty things. Too much pressure can also make it do unpleasant things.

It could be a cleaning problem, and I would definately check that too. But the symptoms you describe sound to me like a pressure issue.

[Vric]

Look like metal flake are the problem. It's strange cos my HP-CP have an even smaller nozzle and I can spray metallic paint. Ok every 2 or 3 minutes I have to pull the trigger a bit more on a piece of paper (to unblock the nozzle), but it work..

I use Isopropyl as thinner.

[badi]

Metallic ink have small pieces of metal inside.

I do not use metallic paints from tamiya, after some time stored it intends to separate in two fases. Metallic powder in the bottom of recipient and solvent above it.

You have to mix it very carefully and somtimes even if you do that, the paint is lost. Once it is separeted it is difficult to solve it again. Probably big pieces of cured paint is getting inside your airbrush.

I prepare my own metallic inks with very thin material. You can find it at some places which sells school materials, like books, pencils and etc. It has very thin aluminum powder, or gold powder etc. I mixture with some acrylic coat and with apropiate solvent.

that is the way I do.