At the end of my tether with my airbrush

[sideshowbob]

Hi All,

been having problems with my airbrush recently and im really fed up with it. I bought it (premiair G35) about a month ago along with a bambi compressor because it was near to silent and had a 24 litre tank. Ever since everything has been great. The tamiya paints i use have been going on like a dream with a perfect finish every time. Until last week.

Ive started getting an unsatisfactory finish when i spray. Its most obvious with gloss colours and some of the semi gloss colours like the semi gloss black. Its almost as if the paint isnt atomizing properly. When i spray gloss the paint looks quite rough like the particles have suddenly got larger. With semi gloss its the same but some particles look shiny and some look matt. Its meant that my current build is at a standstill. Ive repainted the bodywork for the F1 car im working on about 10-12 times and cant get it even slightly acceptable. Its a shame because ive just managed to get hold of my dream kit, a Tamiya 1/12 Porsche 935 in martini colours, but there is no way i can undertake it with things as they are.

I havent changed my paint mix (and all the paints are quite new tamiya acrylics), the air pressure is the same (15-20 psi, although i have tried different pressures), i have tried to clean the airbrush thoroughly with IPA. Ive looked at the needle through a loupe and it seems to be ok. Im really at a loss.

 

[AlanG]

Clean the brush again and check your seals. Also what conditions are you spraying in? You do have a water trap fitted to your hose line?

 

[Ian M]

When you say you have cleaned it thoroughly do you mean you striped it down? I have done a good clean before thinking things where clean. Then I striped it down. Using a between the teeth tooth brush, you know looks like a mini bottle brush, I gave the part the nozzle screws into a scrub with the brush and some airbrush cleaner. Trust me I was amazed at how much crud came out. The actual nozzle was placed in the top of a paint tin, humbrol ones are good. then placed ontop on the radiator to gently warm it. A poke around with a fine paint brush inside turned the white brush black with gunk. Reassembled and blasted through with cleaner and it was as good as new.

As Allyne says a moisture trap is a must. If you dont have one get one.

The way you describe it I could also suspect the temperature might have a hand in it. Sandpaper effect is most often due to the paint drying before it hits the surface. Are you spraying further away than you used to? Have you turned up the heating (well it is winter)?

Cleaning an airbrush with IPA sounds like a waste of beer to me. :laughing:

Ian M

 

[sideshowbob]

Clean the brush again and check your seals. Also what conditions are you spraying in? You do have a water trap fitted to your hose line?

My compressor has a water trap fitted at the regulator. Ive also just ordered one of those mini water traps that fit to the airbrush handle. How do i check my seals?

When you say you have cleaned it thoroughly do you mean you striped it down? I have done a good clean before thinking things where clean. Then I striped it down. Using a between the teeth tooth brush, you know looks like a mini bottle brush, I gave the part the nozzle screws into a scrub with the brush and some airbrush cleaner. Trust me I was amazed at how much crud came out. The actual nozzle was placed in the top of a paint tin, humbrol ones are good. then placed ontop on the radiator to gently warm it. A poke around with a fine paint brush inside turned the white brush black with gunk. Reassembled and blasted through with cleaner and it was as good as new.As Allyne says a moisture trap is a must. If you dont have one get one.

The way you describe it I could also suspect the temperature might have a hand in it. Sandpaper effect is most often due to the paint drying before it hits the surface. Are you spraying further away than you used to? Have you turned up the heating (well it is winter)?

Cleaning an airbrush with IPA sounds like a waste of beer to me. :Laughing:

Ian M

Temperature hasnt changed in the room. I dont like it hot so i never let it get above about 18C. I did strip the brush down when i cleaned it. I removed the needle and wiped it clean with IPA. I then removed everything else including the nozzle and soaked it in createx airbrush cleaner for a few hours. I didnt give it a scrub out with a brush because i didnt have anything appropriate, but i have ordered some brushes, picks, and a nozzle reamer from everythingairbrush.com so will try these when they arrive. I have also ordered a new needle and nozzle so if all else fails i can try them.

I havent changed the distance im spraying from, although i did think that perhaps the paint could be drying before it reached the model. But didnt know why. Is there anything else that can cause this? If the cleaning and the spare parts dont help im at a real loss and will probably have to buy a new airbrush (although cant really afford it at the moment) Thank you everyone for all the ideas thus far.

 

[AlanG]

What are you thinning the Tamiya paints with? I only use Tamiya thinners for their paint as i know it has a retarder in it.

 

[sideshowbob]

Im using the Tamiya thinners. The funny thing is is that these are all things i havent changed. The type of thinner, the mix ratio, the pressure, the distance from the model, the temperature in the room. So something else must have changed, i just cant work out what. Thanks for the idea tho, it all helps.

Ive just drained the tank on the compressor to release any excess moisture as well as checking the water trap which was empty.

 

[AlanG]

If you haven't changed anything and the environment in which you paint is the same then it all points to your airbrush in my opinion

 

[treyzx10r]

Tim,I'm with Ian unless you really really clean the internals with a good fine brush you're probably not getting it clean. Glad to hear you ordered all the cleaning gear hope you get it sorted.

 

[treyzx10r]

I think this thread may help you out its a good tutoral

http://www.scale-models.co.uk/tutorials/11310-thorough-airbrush-clean-how-video.html

 

[sprayman]

The smallest fibre or dried paint in an airbrush can bring your production to a stand still,try a full strip down as mentioned and try and use a a few drops of cellulose thinner to aid your cleaning, IPA is fine but when paint is dry it has litttle effect in cleaning the internal parts of an airbrush.

Now Im a Tamiya paint fan, and gloss paints semi or full need more thinner than usual, try a 60:40 thinner to paint ratio, and lower the pressure to about 15-20 psi, and try many light passes to build up the colour, I found this a good way to build up any gloss coat. Gloss paints tend to be slightley thicker than mat paints, due to the gloss medium.

 

[sideshowbob]

First of all, Thank you to everyone for the overwhelmingly helpful response!

The cleaning tools arrived today and i immediately set to work. Using the nozzle reamer i managed to get a very small amount of hardened paint out of the nozzle. Fired up the airbrush and things certainly seemed to improve. My gloss technique still leaves alot to be desired but things are certainly better. I have a very special (to me) build coming up and im mentally trying to prepare myself. Being able to airbrush again is a major part of that. So once again you have all been great, Thank you.