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So, the most common cause I've heard of causing spatter/spitting problems is water in the air line. I let the thing blow on my face for a bit, and indeed, some moisture, Hrm.

I hadnt had any trouble with it, and I've got one of these dealies, http://www.tcpglobal.com/airbrushdepot/html/TFR-2000.html

But I have to say, I'm not entirely sure what could be wrong with it. I havent seen any water in the trap, but I've only put maybe a half dozen hours of use into this thing since I got it, I cant imagine it's busted already.

Thoughts?

Moisture is a possibility - however, I tend to look closer at the consistency of the paint and of course tip dry (and sometimes a bent needle).

I am a bit of a paranoid nut job when it comes to moisture and my paints. A big part of that is because half the time I am painting - I am not using water based paints...so a little water will ruin them.

On my compressor I have an expansion style moisture trap like that one. I have a secondary trap right before the supply line goes into the attic and then I have a molecular sieve moisture trap at my airbrushing booth just before the manifold. I prefer the molecular sieve style traps and find that they do a better job at removing moisture, but they do need more maintenance (have to cook off the moisture every now and then or replace the beads when they become water logged).

Blowing on your face (or anywhere else) isn't necessarily indicative of moisture in the line though. When the compressed air has a chance to expand, it will cool rapidly and can cause moisture from the air to condense (you can see this happen with those big potato guns...a cloud forms at the muzzle when they fire - even when using perfectly dry gas like Nitrogen or CO2). It is the gas law.

If the paint is too thick - you can get spatter if your pressure isn't high enough. Need enough air to vaporize the paint.

The other thing is to check for tip dry. When an obstruction is in the air path - that will cause the paint to gather in the vortices and spatter. If there isn't any dry paint - look close at the needle. The tip may be bent ever so slightly. Again - creates a vortices and there you have it.

Sort of an aside - but that is a common technique for things like star fields...hold a pencil in the path of the air/paint and the splatters become stars.

Anywho, thin your paints a bit more. Crank up the air pressure a bit and it should sort itself out provided that there isn't a mechanical problem like a bent needle.

I thinned the paint out quite a bit, but I suppose I can try a bit more. In my last batch I think the paint was too thin, and it pooled a bit when I was spraying.

I'm honestly not entirely sure how to adjust the pressure on my compressor. I'm pretty new to this whole thing. :S

I was looking as closely as I could at the needle, and it seems ok. I just replaced it with a slighly bigger .8mm model a few weeks ago, and it did wonders for the usability.

That dial is the pressure gauge, and the black knurled knob on top of the assembly is probably the pressure control. Just turn the knob while running the compressor and you should see the pressure gauge respond.

Water in the air comes from the compressor running hot.
Its inevitable really, as you run the motor it gradually warms up through friction of its own moving parts. Then the warm air coming out of the compressor condenses in tanks and hoses on its way to the air tool.

The regulator you have is also a moisture trap, You cna also get in-line one that go mid hose, and ones that attach directly to the airbrush.
Personally I use all of those option at the same time.

But you could just turn off the compressor and go again later when its cooled off some.

All compressors will have a 'working time' which is how many hours a day it was intended to be used. Most hobby compressors are quite low on this. (rightfully so as we're not running a painting business spraying 8-12 hours a day for profit)

The alternative is to have an oil cooled motor, but then we need to filter oil from the airline instead, which uses all the same filters

Having a tank attached to the compressor can help improve its running time by letting it stop once in a while. But even still moisture will happen at some point. And it will make any painting run really. - its an absolute nightmare for custom car painters!

Are you getting prolonged and consistent spatter or just occasional spatter? If it's just happening intermittently it could be as simple as paint collecting in the crown tip and then getting thrown onto your model. This is one of the reasons I tend to remove the crown before spraying.

The compressor heats up due to Boyle's Law.

 Dullspork wrote:
Are you getting prolonged and consistent spatter or just occasional spatter? If it's just happening intermittently it could be as simple as paint collecting in the crown tip and then getting thrown onto your model. This is one of the reasons I tend to remove the crown before spraying.

Another good tip.

I also remove the needle guard during painting.

Although my shiny new airbrush has a differently designed guard;

this H&S Evolution CR plus (infinity had this first) has a needle guard that allows you to clean tip dry without removing the guard, so as to save on the need to remove it.
Down side is that it offers little in the way of horizontal protection, but ze Germans have quite likely determined that most needle damage comes from a verticle motion?
(H&S are the dons of airbrush design btw, theyre often overlooked, Vallejo ship H&S with their airbrushing kits too)

Much appreciate the advice all around. ^_^

The spatter I was getting was pretty consistent. I havent booted the beast back up since, but I'm priming some tau this evening with a new brand, we'll see how it goes!