Acrylics clog my airbrush tip

[rschaffter]

Yeah I never really was inspired to try any enamels myself due in part to the fumes. 

I once painted the inside of a 1970 VW Bug with spray paint, so my body already has been exposed to a lifetime of fume-inhaling.

Me too (same year!), and the outside of the bug as well.  I blew my nose afterward, and it was blue... 

[tom mann]

Me too (same year!), and the outside of the bug as well.  I blew my nose afterward, and it was blue... 

Funny, I also painted mine inside and out with white rattle cans.  Amazingly, after a good wet sanding down to 1200 and some rubbing compound and wax, the finish didn't look half bad.

[AlkemScaleModels]

I use a Iwata Eclipse CS airbrush , designed for acrylics. From their website

HP-CS Airbrush — This gravity-feed airbrush features a unique 0.35 mm needle and nozzle combination for fine-detail spraying, but with high paint-flow capacity. A generous 1/3 oz size cup is designed with a new funnel shape, which makes for easy cleanup and more efficient paint flow. Automotive artists, fine artists, and students will appreciate how well the HP-CS sprays heavier acrylics and textile colors, while maintaining high-detail spray characteristics.

It usually works great, but will clog eventually when spraying acrylics.
I find that Vallejo Model Air paints thinned a about 20-40 percent with Vallejo thinner tends to forestall clogging.

I keep a spray bottle of straight ammonia for cleaning the airbrush. I use that plus Medea Airbrush cleaner and water.

One problem  I find is that some paint leaks into the air valve mechanism. So after spraying I hit that area with a shot of ammonia and work the valve. That keeps it clean for the next time.

[craigolio1]

Thanks everyone. I have a Paasche VL and I usually spray at 20-25psi. However I don't use a filter and I usually use a dropper to put the paint in the cup and thin it in there. When a bottle gets low enough I'll thin in the bottle. The True Line Trains paints I shoot without thinning which works really well. Well, except for the clogging. If I thin them I find they are just too thin. I have thinned them with about 10% water but that doesn't change anything very much. Thinning with alcohol causes them to gel.

I'm going to get some retarder and try keeping the tip wet between sprays.

I'm really looking forward to trying the True Colour paints.

Thanks, Craig

[wcfn100]

Thanks everyone. I have a Paasche VL and I usually spray at 20-25psi.

I have the same airbrush.  I assume you're using the largest needle.  Try spraying at a lower PSI . 

Jason

[craigolio1]

I have the same airbrush.  I assume you're using the largest needle.  Try spraying at a lower PSI . 

Jason

Yes. Maybe I forgot to mention that. I am using the largest needle.

I will try a lower pressure.

Thanks

[wcfn100]

Yes. Maybe I forgot to mention that. I am using the largest needle.

I will try a lower pressure.

Thanks

If lowering the pressure isn't working (or maybe seems worse), try adjusting the paint/thinner mix a couple times before giving up on it.

The Paasche VL is the only brush I've used for 10+ years.  I have had issues on occasion, but over a large sampling, I can say that the air brush isn't the "problem" but it can be if the paint and pressure aren't right.  If I'm painting for any length of time, I do expect a bit of paint dried on the tip at some point, but obviously clogging is a much bigger and unacceptable issue.

And just so other variables are covered,  I never shake my paint, only stir with an electric stirrer.  I also only use distilled water or sometime Future clear acrylic as thinners.  Not saying any of this is better than anyone else's way, it's just the way I do it in regards to any advice I might give.

One last thing to look at is whether you're opening the tip all the way when you're painting.  Sometimes it feels like you can get more control by feathering the trigger and maybe not keeping wide open, but than there's no advantage to using the largest tip.

Good luck.

Jason

[craigolio1]

Jason,

I agree with everything you said there and then when I read the last point I had an ah ha moment. I am feathering the tip to get less paint and have more control. So basically I'm using a number 3 but reducing it to a number 1. This never occurred to me. Instead of doing this I will turn down the pressure and if I have to, thin it a little, but I imagine just a pressure change will do. I think we've nailed it. What I'll do is turn the pressure down and then slowly turn it up until I get the desired application rate and then see how it goes.

And PS, I love my VL. Hasn't failed me and I used it for the first time 21 years ago.....   But not with acrylics.

Craig

[tom mann]

Unless you want a slightly textured surface, there isn't a time when you wouldn't thin acrylics.  For fade/glaze coats, you want them thinned a lot.  For other applications, thin a little.  For something like wheels and trucks that have texture in real life, use straight.

[craigolio1]

I would normally agree but the True Line Trains paint says not to thin and it goes on quite nicely. I tried thinning it about 20% once and was too thin, but then maybe I sprayed it at too high a pressure and bathed my model.

I'll revisit this and post my results.

Thanks for your input.

Craig

[garethashenden]

Yes. Maybe I forgot to mention that. I am using the largest needle.

I will try a lower pressure.

Thanks

If that doesn't work try a higher pressure. May sound strange or wrong, but I've had good luck at 40psi.

[wcfn100]

but I've had good luck at 40psi.

No you haven't.  Your paint is going on dry.

I don't like to get into right and wrong when it comes to painting because there are so many variables, but spraying acrylics at high pressure is simply not good advice.  I 100% understand why you think it's working because I've been there.  But if you're spraying at 40psi, your paint is drying in the air before it hits the model.

I've also been down this discussion road before, so I won't waste anymore time except to say I strongly recommend against this.

Jason

[amato1969]

I don't like to get into right and wrong when it comes to painting because there are so many variables, but spraying acrylics at high pressure is simply not good advice.  I 100% understand why you think it's working because I've been there.  But if you're spraying at 40psi, your paint is drying in the air before it hits the model.

+1 to what Jason writes.  Low pressure, some acrylic retarder, and spraying close to the model are key to a smooth finish.

  Frank

[Kisatchie]

I don't like to get into right and wrong when it comes to painting because there are so many variables, but spraying acrylics at high pressure is simply not good advice....  But if you're spraying at 40psi, your paint is drying in the air before it hits the model....

Hmm... no wonder I get
lousy results spraying at
800 psi...

[tom mann]

Paint spraying discussions are a lot like decaling discussions, in that a lot of ideas are presented that "work" but the results aren't always good when viewed up close.  If the painted surface looks like orange peel, the paint is partially drying on the model.  This usually is caused by high pressure and thick paint.  Does it "work"?  Sure, in that the end result moved the paint to where you want it.