Good morning, everyone. After a false start a long time ago, I have used ModelAir paint on my last two paint jobs with astoudingly good results; I want to use this paint for the rest of my hobby career. However, I'm having an issue with it clogging my Iwata HP-CH airbrush.
I am using ModelAir paint and a Vallejo thinner I've had for some time. This thinner is not clear; it looks like diluted white glue when you squeeze it from the bottle. I've experimented with the ratio from 10 drops paint/4 drops thinner up to 50/50 paint thinnner. I put the paint directly in the airbrush and mix it with a soft brush. I get a huge paint buildup on the nozzle of the airbrush which is very hard to remove with any kind of thinner, and it is also building up internally around the needle. Again, the airbrush has been very hard to clean compared to other paints.
Can someone tell me what I'm doing wrong? Can other thinners work? I've considered trying Tamiya thinner but haven't tried it yet. As always, I greatly appreciate the feedback. I have a feeling I"m fairly close to finding the solution here, and I'll sure be happy when I do; this is the first paint I've tried that really does what you want it to do when painting armor.

Bill,
What you are experiencing is that your model air paints are drying in the brush & or building up on nozzle & needle. DO NOT use Tamiya thinner!!! This is a synthetic laquer thinner and Acrylicos Valljo paints are latex acrylics........this would make a nasty mess in your airbrush. A few things you can do.....
1. Add an acrylic retarder to your paint. This is available through Acrylicos Vallejo as well as different brands from craft & art stores,
2. Use Vallejo airbrush cleaner to clean you brush, it makes clean up between colors much less painfull. Simply cut the product 50/50 with water or use direct when you need a more thurough cleaning.
3. When you are painting, keep a damp cloth handy. Simply clean the nozzle of paint build up every so often.
4. Try to add small amounts of paint you brush when you load up to paint. If you add a lot of paint to your airbrush and paint at a slower pace.....you will experience your paint drying in the brush.
If you only have a small amount of paint in your brush and you paint quicker ( not in a rush mind you ) this will also help with this issue.
Please let me know if these tips work for you. This is about how I paint almost everyday & these tips have worked for me. I run through a Badger at about 18psi for narmal coverage.

Thanks for the tips, Iain. A couple of questions: I gather you dampen the cloth with Vallejo cleaner? I usually use a QTip to clean the nozzle but will try the cloth; that may work better. Second, what is your definition of small paint batch? My typical load has been about 25 drops of paint; perhaps I should try half of that?
Thanks again
Bill

Bill,
I am glad that these tips can give you some directions to try. I also am a huge fan of Vallejo's paint and hope that you can work through the issue so that you can get the full benefit from the model air range of colors.
As for quantity, 25 drops seems like a lot of paint but honostly I have never counted so this could be correct. I would guess that I use about 1/2 that amount. It is much easier to use a small amount , clean the brush a little, and reload. Much easier than overloading the brush & waisting a lot of paint, time, and patients in an effort to clean a gummed up airbrush!

Hi Bill like lain said Vallejo cleaner is a must! Cheers Geraint Happy air brushing

Bill,
Iain offered some excellent advice! My own experience with airbrushing both Vallejo Mdl Air and Model Color is very positive. I typically use a ratio of three parts paint, two parts distilled water, and one-part Vallejo Thinner (I believe it acts as a binder for the pigment). I shoot at about 14psi through my Iwata and always get both excellent coverage and very fine lines when I need them. However, like you, I get accumulations drying on the tip ... I think that is just an issue inherent to the acrylic paint. I tried adding retarder, but it just upset my paint viscosity to the point that airbrushing was frustrating. Therefore, I just keep a Q-tip moistened with water handy and every few minutes I will gently clean the tip .... takes about 10 seconds and I'm ready to paint again. Also, although not recommended, I shoot with the tips' protective housing removed - exposing the naked needle, but making cleaning much easier.

Kirchoff

I get the same problems as Mike described. Some water and a Q-Tip sorts it out- I also find a quick full-on blast with the airbrush sometimes does the trick aswell.

Wow, thanks so much to all of you for the tips, this helps like crazy. One last question to Iain; I did buy some retarder today; it is very vague on the ratio; it goes from 1:8 (paint) to 1:1. What ratio do you use, Iain? Also appreciate the tip on the distilled water as thinner; I'm going to try that as well. I'm sure with all this great advice I will find something that works well for me. We're certainly all in agreement with the ModelAir paint; the stuff, to me, is more of a tint than a paint, which is just great for buiding up color; also the eyedropper bottles are great for doing ratios with other colors so you can be consistent.

Hi

Don't forget that Vallejo’s own thinner does contain a retarder and adding more can make the paint refuse to dry.

When I used to use Vallejo paints I found I got the best results using Vallejo Airbrush cleaner as a thinner.

One other thing to note is that paint drying on the needle tip is quite common when using acrylics as they can dry to quickly hence the need for a retarder.

One other thing you can try if you’re not already doing this is to lower the air pressure on your compressor as this slows down the paint delivery which also slows down the paint drying time. If you are not already doing so try spraying between 12 & 15 PSI, I find the combination of using Vallejo cleaner as a thinner and spraying at below 15 PSI. I find doing this almost completely removes all problems with paint drying on the airbrush needles tip.

Hope this has been of help.

Paul

Hi Bill,

Here's my piece of advice:

I thin the colour one drop of Vallejo thinner for every three drops of paint. Mostly i use batches of twelve drops maximum. To that I add ONE drop of Liquitex flowaid. Works really nice for a long time.
Then some buildup occurs which I just carefully pull from the needle with my fingernails of indexfinger and thumb. After that I quickly douse the needle with a soft brush and Vallejo airbrush cleaner and I'm set to go again for some time.
I do this with the whole airbrush fully assembled just between coats, mind you, I just spray without the neelde protection cap.

I use an Iwata Revolution HP cri.

Hope this helps.

Thanks again to everyone for their advice. I tried some of your advice last night and sprayed with no dreaded buidup. I know I have to fine tune the mix but I'm on the right track. Thanks again to everyone for their time.