Airbrush Issues

[HarasinCreed]

I bought an airbrush a little while ago and at first the paint job was fantastic and completely smooth. Now after about the 7th use i find that the paint doesnt apply a smooth coat but more of a splattered one. Note it is not spitting the paint out every once in a while it just is not giving a smooth and consistant flow. Also the paint sometimes does not come out at all and i have to pull the needle back and forth and it works alright for a while then?

 

So any help would be much appreciated.

Ed

[Gurth]

Sounds to me like your problems could well be caused by paint that is not thin enough, and an airbrush that is not clean enough.

[winterdyne]

Yup. Strip it, clean it. You likely have paint build up on the needle and in the nozzle. You should really do a full strip and clean at the end of each session anyway.

[Tanhausen]

Actually, I have a similar problem: bubbles in the paint up.

 

Obviously it means something is clogged... so I've stripped it, kept in isopropylic alcohol for days (done this several times) and run it through an ultrasonic cleaner.

 

And it still does the same from time to time.

 

Using Tamiya thinner (X-20a?) usually works, just run it straight into the AB and blow it all out.

 

And keep the paints thin!!!!

 

All my problems started when I tested some new AB paints (Jaquard or something like that)... without noticing they are intended for .5 AB and mine is .25 :(

 

When AB works properly its soooo nice... but when it starts messing up, its SO frustrating!

 

Edit:

 

Posted at the same time as winterdyne... what do you use to clean the AB?

[winterdyne]

I blast through windscreen wash during a session, wiping out with a tissue (not loo roll). Occasionally clean the needle with some cellulose thinner on a tissue. At the end of the session, shoot through cellulose, bubble it (hold the needle back, cover the nozzle, press the trigger), the air agitates the thinner in the body and helps clean. Then shoot through some more. Strip down, soak nozzle and caps in thinner, clean with q-tips, and sharpened cocktail stick for nozzle (be gentle!). Clean body and cup throroughly, reassemble, shoot through some more windscreen wash, then water, then dry it out by just shooting air.

[Tanhausen]

Language issues...

 

- windscreen was = window cleaner?

- tissue = kitchen paper or some kind of cloth?

- is cellulose thinner the same as Tamiya acrylic thinner?

- q-tip = cotton buds for ears?

 

Probably thats where I make my mistake... when I change colours, I simply pour the new paint and wait until it comes out of the new colour.

 

Thanks!

[winterdyne]

windscreen wash = car windshield fluid (blue stuff, high alcohol content plus surfactants)

tissue = paper napkins - kitchen roll and toilet paper are usually too fibrous. You don't want to leave paper fibres behind.

cellulose thinner is NOT tamiya thinner - Tamiya thinner is basically Isopropyl alcohol. The cellulose thinners I use contains Methyl Ethyl Ketone and Methyl Isobutyl Ketone. Used in car lacquers. Very nasty stuff, quite toxic but an excellent cleaner. Ensure adequate ventilation and don't breathe it. Or get it on your skin a lot. Coincidentally, it melts plastic like you wouldn't believe and makes a reasonable poly cement substitute in a pinch.

Q-tip = cotton bud for ears.

 

ALWAYS flush through when changing colour.

[Tanhausen]

Ketone as in the solvent for paints? I'll try some universal solvent the next time, thanks for the tip.

 

Also... I usually just blow the remains in a normal plastic cup... is a "vacuum" pot a better way out? I don't really know how they work, but one of the "good painter" guys in my local area uses it...and I'd say you fall in the category of "good painter" for BnC :D

[CainTheHunter]

Ketone isn't the same good ole' acetone? Cause "ensure adequate ventilation, don't breathe it or get it on your skin a lot, melts plastic" sounds very much like it. It dissolves any acryllic paint in seconds and can be used for stripping metal minis - could this be the same?

[winterdyne]

No it's not acetone, acetone is friendly in comparison. @Tanhausen - yeah, probably. 'Universal Solvent' sounds about right. You'll probably find the bottle marked '100% pure solvent' or something similar. Seriously though guys, it is nasty stuff - over exposure can lead to a headache that takes days to shift, dizziness, weakness the whole works. A full respirator is used in car body shops handling this stuff for a reason.

 

I used to use this stuff for stripping metal minis, but the toxicity has left me preferring simple green for both metal and plastic - now it's only use is in clearing the airbrush, and that for the most part at the end of a session.

 

Oh - avoid VMC browns. They're awful to try and spray. ;-)

[Tanhausen]

I try and use only VAC only... but sometimes have to use VMC. Flat tan works out nicely.

 

I paint DW so... I need a brown base coat!

[CainTheHunter]

No it's not acetone, acetone is friendly in comparison. @Tanhausen - yeah, probably. 'Universal Solvent' sounds about right. You'll probably find the bottle marked '100% pure solvent' or something similar. Seriously though guys, it is nasty stuff - over exposure can lead to a headache that takes days to shift, dizziness, weakness the whole works. A full respirator is used in car body shops handling this stuff for a reason.

 

If aceton is friendly in comparison, then ketone must be tough stuff :)

But it is funny - the difficulties and challenges people tend to venture into just to make their small plastic toy soldiers look good!

[ShinyRhino]

I get similar issues, and it's incredibly frustrating.

I find one of my major problems to be the spitting, and also paint popping out of the vent hole in the cap for the paint cup. My paints tend to gum up around the needle, and then blast off from time to time onto my model, leaving a lump. It makes me cry :P

[winterdyne]

That problem is helped by using slower-drying mediums (water as opposed to alcohol) and a flow improver, as well as lower pressure - what's happening is the paint is drying on the tip of the needle and in the nozzle, which blocks it - that's why it spurts up through the cup cap. You can also try different types of paint - I love Tamiya paints for airbrushing (using the appropriate thinner, though some folks like Isopropyl Alcohol).

[ShinyRhino]

That problem is helped by using slower-drying mediums (water as opposed to alcohol) and a flow improver, as well as lower pressure - what's happening is the paint is drying on the tip of the needle and in the nozzle, which blocks it - that's why it spurts up through the cup cap. You can also try different types of paint - I love Tamiya paints for airbrushing (using the appropriate thinner, though some folks like Isopropyl Alcohol).

 

Ah, that would make sense, as I use a 50/50 mix of window washer and water when thinning my paints for the airbrush. I'm using Reaper Master Series paints, maybe I'll try some of the drying retarder I have lying around that was recommended by Anne Foerster ages ago.

[HarasinCreed]

Next question. how do u recommend getting paint out of a GW bottle into the airbrush and how do you mix the paint with water without taking half of it back out on your brush?

[Gurth]

You can unscrew the cap of GW paint bottles so you can pour the paint into the airbrush cup. Then add in water (or other thinner) and stir well with a flat stick — not a round one.

[Tanhausen]

Curious... why flat?

[winterdyne]

a round stick just pushes through the thicker lump of paint / pigment in the water. a flat one breaks it up and stirs better.

I add water to the cup first (just a bit) then use an old long-bristle brush to add paint and more water to that as I go along.

[madscuzzy]

One thing to note is also the pressure that you are using. Acrylics and larger molecule stuff like water do require a slightly higher PSI than the thinner based paints. Low pressure tend to allow paint to dry on the tip somewhat faster.

 

Vallejo offers an airbrush thinner that thus far works wonders for me. I used to use ISO as a thinner for my paints but have since switched over to the easier/faster-to-use Vallejo thinner.

 

Airbrushing is similar to painting in a sense that you should 'wash' your brush every few sprays. Covering the head with your finger to trigger bubbly-blowback is useful to declog the nozzle every few mins as it loosens the fine paint in the tip and keeps it from collecting too much.

[HarasinCreed]

Thanks for all the help guys this has really helped!

[Thylacine]

Next question. how do u recommend getting paint out of a GW bottle into the airbrush and how do you mix the paint with water without taking half of it back out on your brush?

 

I use a syringe I find them easier to use that a pipette as they are well marked so measuring the paint to water mix is easy.

 

http://www.growforce.co.uk/products/1061/1...ic-syringe.html

 

For mixing the paint I use a small dough hook shaped piece of paperclip fitted to a roto-tool run at low speed.

 

http://www.thegourmetdepotco.com/store_par...ch=dough%20hook

 

You need to keep your hook in line as if it is off balance it will throw the paint rather than mixing it. I have used the hook mixer for a couple of years now mostly to refresh older paint when using a brush. If you decide to use GW paint in your airbrush you need it to be fresh as it clumps quickly.

 

I run my compressor at 35-40 psi for GW paint, BTW this is my compressor;

 

http://www.supercheapauto.com.au/online-st...=223418#details

 

 

If I was to buy again I would have gone for a larger one when it is on special with tools! I just don't have the space or money to spend on a dedicated hobby compressor.