Airbrushing Advice Needed

[psyberwyche]

Hi guys,

I really need a bit of advice, as I've just had a small airbrush and compressor for Christmas, and can't seem to get it working properly.

The airbrush is this one: http://direct.hobbycraft.co.uk/products-Spraycraft-SP30KC-User-Friendly-Airbrush-Compressor-Kit_344464.htm

The problem is I'm getting a horrible 'dotty' effect on my models, like the paint is shrinking away from the surface. I think maybe the problem is with the consistency of the paint, but I can't seem to find an accurate guideline anywhere (no instructions in the airbrush box about paint mixing).

I started with about 50/50 paint to water. At the moment I'm using about 2 parts Citadel paint to 1 part water. Should it be thicker or thinner? Also, should I use some kind of medium instead of water? I remember reading somewhere that car screenwash works wonders, but not sure whether to try it!

Any advice will be most appreciated!

Regards,

M

[zizi666]

You could always try Golden Airbrush medium to thin your citadel paints : http://www.goldenpaints.com/technicaldata/abmedium.php
However, if I was you, I'd try to get my hands on airbrush paints like the valejo model air range or Golden (for basic colours, beware the transparency of some colours!)

[styx]

I am just getting into airbrushing also, a friend said to use glass cleaner to thin the paints down...he also says if you can get a small strainer, strain the GW paint to get the clumps out that form in their paint, he said it causes that spotting effect you are talking about, it is due to heavy particles in the paint and clogs up the air flow and sputters...

He said he is giving up GW paints in favor of P3 and other paints he can thin down that are not as prone to having clumps (heavy particles).

[Zafarelli]

Sounds like the paint is watered down too much. Go for real airbrush paints as Zizi suggested. I'd recommend the Schmincke brand. Not cheap, but the best I've tried so far. No need to thin these, either.

As for straining, you can use a fine pantyhose. I've seen a professional model maker do this, and it worked fine. I have always braced myself for a fireball from the spray room, though, as he used to smoke while spraying a mixture of 95% thinner and 5% silk-screen printing paint

[psyberwyche]

Thanks guys.

I'm a bit stuck with Citadel paint for this particular project, as I'm base-coating models to add to an existing army. Once they're done, I'll certainly investigate specialist paints. TBH, I've used GW paints in the past (supervised by an old pal who knew what he was doing!), and they worked fine. Going solo for the first time though, and I can't replicate the results!

Sounds like there's too much water, and I should probably try a medium instead of water. I'll order some Golden - will something like Windex do in the short term?

Thanks,

M

[jthomlin]

The paint should be the consistency of milk, pour some down the side of a glass or clear plastic container and you will see that as the milk flows to the bottom it leaves a thin consistent film on the side, you need to mix your paint to the point where it does the same.

As to what to use to thin the paint, Valllejo have an acrylic thinner specially designed for air brushing that should work with GW paint, it has flow improver to help the spray pattern and retarder to help make sure the paint is still wet when it hits the target. You could make your own using water and or acrylic medium, flow improver and  retarder, but I have no idea in what proportions. Window cleaner acts as a flow improver by breaking the surface tension so that my work as well, I have also heard of folks using Isopropyl Alcohol but never tried it.

If you do use water, make sure it is distilled rather than out of the tap.

Cheers!
Joe Thomlinson

[Billchuck]

I thin with isopropyl alcohol, works great.  Test it with the paint before you put it through the airbrush. I've had some paints react weirdly to it, get gummy and stringy rather than mixing properly.  You don't want that to happen inside the airbrush.

Can you take a picture of your problem so we can see?  There's a few different things that could be going on and "dotty" describes many of them 

[psyberwyche]

Thanks guys - I'll try to post a photo of my test piece after work tonight :-)

[Grimmnar]

Use a good airbrush and compressor. Dont get suckered in on package deals. Not usually a good deal.
Use AB paints. There are many. AB paints should already be good from the bottle.
If you have to use non AB paints you are looking for the consistency of skim milk.
Straining is also something to look at. Non AB paints have larger clumps of pigment in them.
Using glass cleaner is not always a good thing. The ammonia in the cleaner isnt good for you to breath. And the glass cleaner without the ammonia is not as good.
AB thinner is best to use with AB paints. Example is Vallejo AB Medium is good for Vallejo AB paints.
Badger is releasing a new set of AB paints. In fact that have an awesome deal on the price.
Remember there is no one AB for all jobs. There are many AB's and types of AB's for a reason. I have seen awesome results from and expert and a $20 AB and i have seen people who cant do a damn thing with a $200 AB. Takes time and practice. No one person knows it all right off the back. Takes time, practice and research. And the will not to get frustrated early and quit.
Thoughts? :-)

Grimm

[Billchuck]

It's possible you're trying to feed it too much paint.  I get that with Creatix's white airbrush paint.  Next time, try not pulling the trigger all the way back.  Push it in and draw it back just enough to get paint to spray out.  Practice on a piece of paper or cardboard, something that contrasts well with the paint.

[Brandlin]

You do not need a special medium to thin. I use citadel and foundry thinned with water regularly.

To stop spotting

- don't over thin - milk consistency
- turn your pressure down a little
- ease your finger on the trigger before you reach the work piece... Don't just ram your brush open.

[Blackwolf]

I think nearly everyone has trouble when first using an airbrush,it took me ages(I have an Paasche double action) and I'm still learning Follow the sage advice of the others and practice; eventually you will like me be saying 'I love my airbrush' I use the thing for all sorts,priming,painting,varnishing; it is an wonderful tool,and can be great fun ,the pleasing effects always amaze me,what more can I say? I love my airbrush 

[Mitch K]

I started with a really rough Humbrol spray gun, and graduated eventually to an Iwata I used when I was a tank / aircraft modeller. My Iwata bought the farm a little while back and I'm left with a couple of cheapy copies I use now, one for spraying varnish and another I use for paintwork.

If its spotting, as has been said, check viscosity. I like Liquitex airbrush medium as my viscosity controller, along with a touch of flow improver.

The other thing to check is pressure. If you have too much air pressure it tends to cause the stream to break up. I have a filter/dryer/pressure gauge on the side of my spray box that allows me to fiddle with the pressure as I go along.

The final thing is are you too far from the workpiece?

Stick with it. Airbrushes are wonderful tools and bring a dimension to your work nothing else can.