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I've not really much experience airbrushing but i can never seem to get a really nice smooth finish on my models. It always has an almost dusty texture to it. I thought i was going something very wrong so today after giving something a base coat and getting fed up i decided to go back to using paper to test.

I have a premair g35 at the minute and no matter what i do, how thin i go, what pressure i can never seem to get a nice smooth finish out of my brush. See pics. This happens with both citadel and tamiya paints with an acrylic thinner. Havent tried with the enamels yet. These pics are from a few test pieces of a4 and i made sure the brush was thoroughly disassembled and cleaned every refill.

Notice the "spattering" around the edges of the paint.





And the effect it leaves on a model.


Im just trying to pinpoint the issue. Is this moisture in the air line?, moister in the air, dust? I'm happy to replace or add equipment but really want to find out what the issue is first

Likely the opposite.

Moisture in the line will make the brush spit, and you'll end up with a spotty finish as the water hits the model and paint can't adhere to the droplets.

The dusty finish is likely the paint drying in mid air, suggesting that either the air flow is too high, or you're holding the brush too far away (one can lead to the other, high pressure means holding the brush further away otherwise you get spider webbing.)

The spattering can be a number of reasons too, but the most likely is either the paint is still too thick, despite using thinners (which again may feed back into your other problems as you'd need to set the PSI high to get the paint out) or it may be a damaged needle or some dried paint is sitting somewhere prominent. You don't seem to have gone below 15 PSI in your test, and I'd consider 20 to be on he high side.

I'd go for thinning your paint more, turning your PSI down and a good clean and then see where you are.

Another idea might be invest in some proper airbrush paint, not necessarily to replace everything you use, but to get an idea of how paint looks when it's ready to go through a brush, and then you can use that as a baseline to thin your other, non airbrush, paints.

 Azreal13 wrote:
Another idea might be invest in some proper airbrush paint, not necessarily to replace everything you use, but to get an idea of how paint looks when it's ready to go through a brush, and then you can use that as a baseline to thin your other, non airbrush, paints.

I'm reading a lot about Airbrushing as I'm looking to potentially invest in one soon.

Does proper airbrush paint mean that it's been thinned already, or is it somehow a different kind of paint than acrylic? I'm a super newb with this so sorry of that is a silly question.

Mdlbuildr wrote:

 Azreal13 wrote:
Another idea might be invest in some proper airbrush paint, not necessarily to replace everything you use, but to get an idea of how paint looks when it's ready to go through a brush, and then you can use that as a baseline to thin your other, non airbrush, paints.

I'm reading a lot about Airbrushing as I'm looking to potentially invest in one soon.

Does proper airbrush paint mean that it's been thinned already, or is it somehow a different kind of paint than acrylic? I'm a super newb with this so sorry of that is a silly question.

It's basically just thinned for you, which took a huge amount of headache out of the equation when I started learning how to use my airbrush (I'm still quite new at it myself). I recommend Vallejo's Air line of airbrush paints. They work very well and match up nicely to most of the standard GW colors.

Which isn't to say that they're flawless, they thicken with age, metallics can sometimes be a little fussy etc etc. But a brand new, non metallic, formulated for airbrush, paint is a very good way to learn what the paint needs to look like, and goes some way to eliminating variables when solving issues.

I will try again tomorrow and go over the top with thinner.

On one of my sheets i did draw a line, add thinner, draw a line, add thinner etc to see if it made a difference but it started getting pretty damn thin

What Az has said is pretty much right, to add to that.

What are you using for a thinner? Are you using the same thinner for both Tamiya and Citadel paints? Tamiya paints are great for airbrushing, they're one of my go-to brands, but they are heavily alcohol based so like to have a different thinner and don't mix particularly well with water based acrylics (like Citadel, Vallejo, P3, etc).

You can try thinning more and maybe get closer to the surface, which will in turn mean you probably want to turn down the pressure.

But on top of that you can also add more drying retarder and/or flow improver to stop the paint drying in the air or on the needle.

When you thin your own paints, the mixture of thinner to paint to needle size to airbrush pressure (PSI) is a delicate one. If you overthin your paint and apply too much pressure for your needle size, you'll get some ugly splatters. If you underthin your paint and don't apply enough pressure, it will probably all jam up and nothing will come out. Also, check your crown: when you thin your own paint, it's possible that you have an unusually high amount of paint drying at the tip and accumulating there. If there's too much paint gunked up there, it will interrupt the cone of paint coming out of the airbrush, and disperse it in a way that you don't want. It also accumulates and gets worse. A q-tip fixes the problem.

Mdlbuildr wrote:
Does proper airbrush paint mean that it's been thinned already, or is it somehow a different kind of paint than acrylic? I'm a super newb with this so sorry of that is a silly question.

"Proper airbrush paint" is pigment (the same stuff they use for bristled-brush paints) mixed with a cocktail of medium, thinners, flow improvers, and retarders to make it so that paint flows better in the airbrush, dries less on the tip and in the nozzle, and with the most popular needle sizes (in the range of about 0.25mm - 0.55mm) can be used neat -- that is, with nothing else added. But that doesn't mean that it might not help to thin it, just like a GW layer paint can be used neat, but will often come out better thinned a little, if only with water.

There is totally nothing wrong with thinning your own paints, but Az is right: when you buy premixed Airbrush cocktails, you get a good idea of how it SHOULD work, and then you can go from there.

Potentially, with Vallejo, thinning your own paints is better, because there is terrible color match between VMC and VMA, for instance (most of the colors don't line up....). This is because it's possible to take a VMC paint, and thin it to the correct viscosity for an airbrush, but not really possible to thicken Vallejo Model Air so that it works for the brush applications that require thicker paint. With Citadel Base/Layer/Air, the colors are a perfect match, and in fairness, a good chunk of Vallejo Game Color and Game Air pretty good matches.

The other benefit of premixed airbrush paint is that it's always the same consistency. it's a real pain in the rear when you're mixing your own to always get the same/right proportion.

AllSeeingSkink wrote:
What Az has said is pretty much right, to add to that.

What are you using for a thinner? Are you using the same thinner for both Tamiya and Citadel paints? Tamiya paints are great for airbrushing, they're one of my go-to brands, but they are heavily alcohol based so like to have a different thinner and don't mix particularly well with water based acrylics (like Citadel, Vallejo, P3, etc).

You can try thinning more and maybe get closer to the surface, which will in turn mean you probably want to turn down the pressure.

But on top of that you can also add more drying retarder and/or flow improver to stop the paint drying in the air or on the needle.

I do prefer the tamiya paints as they seem to go through easier. I am using the same thinner accross the two brands but it was just the thinner that my local shop sells.

I'm wondering if it is paint drying. As after a couple of runs across the paper and take my finger off and then just apply air a small spatter of paint will come out. Although im unsure what needle i have. I've just ordered some dropper bottles from the almighty 'bay so once ig et the paint to thinner ratio correct i can just stuff it all in a dropper and be done. Currently using 1ml syringes to apply the thinner. Will have to wait till this evening to have another go

Do you know what thinner it is? I could be wrong, but I think if you use an alcohol based thinner with Citadel paints you are probably more likely to get it drying fast or possibly even not quite mixing properly.

For GW paints, Vallejo airbrush thinner works well in my experience. There are others which others can recommend that I haven't tested though. Humbrol acrylic thinner can work with GW paint but it has a large amount of drying retarder which can make it tricky to work with if you're new to airbrushing.

I personally prefer Tamiya paints as well, Tamiya and Gunze are my favourite paints to spray, the problem is the colour range isn't huge and since they don't mix well with water based acrylics it limits options. Actually, I like Testors model master the most for airbrushing, but enamels and enamel thinners have a smell that lingers long after I finish airbrushing and they take longer to dry, so I usually revert to Tamiya and Gunze.

Tamiya paints thin well with their own X20A thinner and even better with a lacquer thinner, my favourite is Gunze's self levelling thinner (basically a mild lacquer thinner with a slightly slower drying time and flows a bit better). If you want to use a lacquer thinner make sure you have good ventilation and ideally your airbrush should have telfon seals rather than rubber seals (particularly the needle packing seal, my AB has a rubber seal for the cup which I don't really care about, lol).

Some people mix their own thinner for Tamiya paints using alcohol and other goodies, I don't have any experience with that but if you want to go down that road, google it, a lot of scale modellers use Tamiya acrylics so there's a lot of information out there on them.

As after a couple of runs across the paper and take my finger off and then just apply air a small spatter of paint will come out.

That is most likely because you are stopping your air before you stop the paint. I assume you're using a standard dual actual where you pull back for paint and push down for air, if you finish spraying and lift your finger up, you'll stop the air but the needle will still be drawn back so a small bit of paint comes out but isn't blown away because you've stopped the air.

Next time you go to spray, you'll get a splatter because that droplet of paint will be blown off. It's also more likely that you have a bit of dried up paint on the tip of the needle which is very bad, dried paint on the needle will stop you from getting a nice cone of spray because paint has to flow across the grime on the needle, disrupting its flow.

So train yourself when you finish a line of spraying, rock the trigger forward to stop the paint first, then lift off to stop the air.

If you still get a small splatter when you apply air after doing that, it means your needle probably isn't seating correctly in your nozzle.

As Talys mentioned, check the nozzle and needle outlet frequently during your spraying session, that area needs to be clean to produce a good spray pattern, if there's any dried up paint sitting on the needle or nozzle exit it will mess up your pattern. That's part of the reason I like to use Gunze's self levelling thinner with Tamiya acrylics, it goes a long way to eliminating paint drying on the needle and in the nozzle. It also stops paint drying in the air as much so you can spray from further away without causing problems and reduces the natural graininess of Tamiya paint.

I've never tried Gunze's self levelling thinner with citadel paints, I imagine it won't work and at worst will turn it to goop in the airbrush. Tamiya and Gunze acrylics are specifically formulated to be compatible with lacquer based products,

AllSeeingSkink wrote:
Do you know what thinner it is? I could be wrong, but I think if you use an alcohol based thinner with Citadel paints you are probably more likely to get it drying fast or possibly even not quite mixing properly.

Hmm, its called "mr stickys" and the only sort of decent info i can find is actually a fellow dakka post using this thinner and tamiya paints having the exact problem as me.
http://www.dakkadakka.com/dakkaforum/posts/list/512317.page

I'm quite happy to switch to tamiya thinners for tamiya paint. Its just would have been nice to get it all from a local store.

AllSeeingSkink wrote:

As after a couple of runs across the paper and take my finger off and then just apply air a small spatter of paint will come out.

That is most likely because you are stopping your air before you stop the paint. I assume you're using a standard dual actual where you pull back for paint and push down for air, if you finish spraying and lift your finger up, you'll stop the air but the needle will still be drawn back so a small bit of paint comes out but isn't blown away because you've stopped the air.

Next time you go to spray, you'll get a splatter because that droplet of paint will be blown off. It's also more likely that you have a bit of dried up paint on the tip of the needle which is very bad, dried paint on the needle will stop you from getting a nice cone of spray because paint has to flow across the grime on the needle, disrupting its flow.

Ah thanks for pointing that out, i did not know that Thanks

From what I can see Mr Sticky's is an alternative to Tamiya's X20A, I have no idea how it compares, I don't think it's available outside of the UK for me to test it either.

Personally I'd stick to something like Vallejo thinner for thinning Vallejo/Citadel/P3/Reaper paints. For thinning Tamiya, well, maybe Mr Sticky's is fine if it's a good copy of X20A as X20A is good.

But Tamiya paints thin even better with Gunze's self levelling thinner if you can get your hands on it. It sprays almost as good as an enamel but with a fast drying time and without the lingering smell of an enamel (it still has a smell, but it's short lived and evaporates fast, just make sure you have good ventilation while spraying which you should really do for any kind of spraying!).

After seeing how this thread has progressed, the first thing I'd check (even before dumping the Mr Sticky's) is whether your needle is staying clean while you spray. The pictures in your original post can definitely be the result of a dirty needle. Check every few lines you spray that the needle is clean, I usually just pinch the needle with a tissue to clean it off. If that's not the problem, then I'd try an alternative to Mr Sticky. If that doesn't fix it, try thinning more, closer range and adjust pressure accordingly.

AllSeeingSkink wrote:
From what I can see Mr Sticky's is an alternative to Tamiya's X20A, I have no idea how it compares, I don't think it's available outside of the UK for me to test it either.

Personally I'd stick to something like Vallejo thinner for thinning Vallejo/Citadel/P3/Reaper paints. For thinning Tamiya, well, maybe Mr Sticky's is fine if it's a good copy of X20A as X20A is good.

But Tamiya paints thin even better with Gunze's self levelling thinner if you can get your hands on it. It sprays almost as good as an enamel but with a fast drying time and without the lingering smell of an enamel (it still has a smell, but it's short lived and evaporates fast, just make sure you have good ventilation while spraying which you should really do for any kind of spraying!).

After seeing how this thread has progressed, the first thing I'd check (even before dumping the Mr Sticky's) is whether your needle is staying clean while you spray. The pictures in your original post can definitely be the result of a dirty needle. Check every few lines you spray that the needle is clean, I usually just pinch the needle with a tissue to clean it off. If that's not the problem, then I'd try an alternative to Mr Sticky. If that doesn't fix it, try thinning more, closer range and adjust pressure accordingly.

The needle is always clean when i remove it as during that test i made sure to disassemble the whole brush between paints and cant say i noticed any paint on the needle but it got cleaned either way. I will be testing more tonight when my daughter is in bed. I dont want to dump the mr sticky yet but i need to order a few supplies anyway so will include an alternative thinner in the batch

Thank you for the advice

Best I can tell, I agree the paint is drying in the air before hitting the surface.
Try spraying a rattle primer can at a surface some 16" away or more for the same effect "fuzzy model".

Could be any the following:
- too much pressure, try sprays at a comfortable distance and lower the pressure..
- too much air flow (I use a flow regulator at the base of my brush).
- too far away, try sprays progressively closer.
- too much alcohol / too little water in carrier, add water.
- least likely is hot weather can quicken dry time in the air. You can try spraying closer.

I use Liquitex airbrush medium, to each their own.

Any spotty sprays can be paint accumulation at the needle tip.
If paints are old, pouring them through a fine mesh screen (paint shops have them) can help get overly large solids out.

Best I can think of from my experience.

Johnson & The Juice Crew wrote:
The needle is always clean when i remove it as during that test i made sure to disassemble the whole brush between paints and cant say i noticed any paint on the needle but it got cleaned either way. I will be testing more tonight when my daughter is in bed. I dont want to dump the mr sticky yet but i need to order a few supplies anyway so will include an alternative thinner in the batch

Thank you for the advice

Just try cleaning the tip during actual painting and see if paint comes off, whether the needle is clean after it's removed isn't really important (as I assume you flush it through with thinner or cleaner before you disassemble anyway), it's whether it's building up right on the tip during painting. Google "tip dry" and you'll see what I mean. Bad tip dry will cause the brush to clog frequently, but moderate tip dry can simply cause a bad spray pattern without clogging completely. If you're getting tip dry you'll need to be cleaning the tip anywhere from every few minutes to every few seconds. You don't fully disassemble, you just clean off the tip with a tissue or cotton bud or even just your fingers, just be careful not to bend the tip.

I like to moisten the end of the cotton bud with thinner when I need to clean it, helps to loft the paint off.

Ok so i didnt get a chance to try stuff the other day but today i got to see if i could get my brush working nice and smooth.

I thinned the paint down so much it was at the point where you couldnt really use it on a model and it was still coming out blotchy. Now many moons ago i picked up an unamed airbrush from a boot fair/yard sale and thought i would give it a go. Its still a dual action but im unsure of the needle size and its a siphon feed which, as i found out, is a lot messier to clean than my gravity premiair.

However the results ended up being night and day. I mixed up a batch of tamiya black paint and its probably about 5 parts thinner to 1 part paint but it was still coming out blotchy from the g35 so i poured the solution out of the cup into my unamed brush and it works fine. Its super smooth and soft. So soft my phone really had trouble focusing which is why i put a syringe in to try and help it focus. I will get some more pics later and see if i can get my phone to focus better when its dark like it was before

Both attempts where the same paint mix @the same pressure @20psi
G35 attempts



And heres what my unnamed brush managed with the exact same paint mix



And a comparison, with the top being the g35 and the bottom being the unnamed



So any ideas as to why my g35 could be doing this? Im going to use the needle out of the unnamed one and see if it makes a difference but it looks quite a bit thicker. Its currently dissasembled and sitting in a tub of airbrush cleaner to see if its something lodged somewhere but it has always been like this, i have never had a super smooth finish from it.

How do you clean your brush?

It's good to run some pipe cleaners or interdental brushes through the passage that leads from the paint cup to the nozzle to make sure that's clean.

Are you confident the nozzle is clean? The smaller nozzles I clean using a toothbrush, I just carefully stick 1 or 2 bristles through the nozzle and use a flossing motion (while everything is nice and wet with cleaner of course). Larger nozzles that doesn't work because my toothbrush bristles aren't long enough, I shove a pipe cleaner in them to clean the bottom half and then carefully use a needle to clean the top half, pushing dried paint through the nozzle and then spraying it through with some airbrush cleaner once it's reassembled.

If that's clean and your needle is clean, check that the needle tip isn't damaged or bent. It can be hard to see, one of my needles had a bump that was so small I couldn't see it, but I could feel it and when I wiped it with a tissue some of the tissue would catch on the bump and tear. I polished the needle to fix it, but that's not always an option and you may need a new one.

You can inspect your nozzle as well and make sure it's not damaged and the needle is seating well.

When the airbrush is assembled look down it and make sure everything is concentric. Make sure the nozzle is concentric with the aircap and make sure when you pull the trigger, the needle pulls straight back in to the nozzle.

Also are you sure it's not a tip dry problem like we mentioned? Tip dry effects different brushes in different amounts. A brush with a long gradually tapering needle will tip dry much faster than one with a more aggressive taper or a dual taper. It's probably not if you thinned the paint 5:1, but still worth checking.

Your psi is WAY to high, you want to be operating below 17, I'll need to check mine when I get home but iirc mine is set to like 10.

Also it's most likely your paints as wel, GW paints arnt really good in an airbrush imo even when thinned.

Get Vallejo game air, it's pre mixed super fine pigments and does magic, make sure your brush is clear. Don't use anything but acrylics, you can gunk up your brush.

Drop psi, get some Vallejo paints, and shake them well.

 Backspacehacker wrote:
Your psi is WAY to high, you want to be operating below 17, I'll need to check mine when I get home but iirc mine is set to like 10.

Unless you're doing fine detail work, there's a pretty wide range of PSI you can spray over before you start getting issues, so I doubt that is it.

Though it is odd that you spray at 20PSI with 5:1 thinned Tamiya paint, I'd guess that's too thin for that pressure. What far are you spraying from? Maybe you already mentioned it and I forgot/missed it, but long distance spraying will cause problems.

Also one thing to keep in mind, cheap hobby compressor regulators are often wrong. The gauges on them often aren't checked and can be off by several PSI quite easily. I know mine reads 5-10PSI high, but I don't care because even if it's wrong it's repeatable. If you have a long hose and the regulator is on the compressor side of the hose you might also need to set your PSI a touch higher to overcome pressure losses in the hose.

Also it's most likely your paints as wel, GW paints arnt really good in an airbrush imo even when thinned.

Get Vallejo game air, it's pre mixed super fine pigments and does magic, make sure your brush is clear. Don't use anything but acrylics, you can gunk up your brush.

Drop psi, get some Vallejo paints, and shake them well.

I've personally never had any problem spraying GW paints.

But either way, Johnny said he was also using Tamiya, and thinning it quite heavily. Tamiya paint is very good for airbrushing, I rate it higher than Vallejo Air (other than the fact it's not pre-thinned).

AllSeeingSkink wrote:
How do you clean your brush?

Between colours i always dissasemble and run a small pipe cleaner through it.

AllSeeingSkink wrote:

Are you confident the nozzle is clean? The smaller nozzles I clean using a toothbrush, I just carefully stick 1 or 2 bristles through the nozzle and use a flossing motion (while everything is nice and wet with cleaner of course). Larger nozzles that doesn't work because my toothbrush bristles aren't long enough, I shove a pipe cleaner in them to clean the bottom half and then carefully use a needle to clean the top half, pushing dried paint through the nozzle and then spraying it through with some airbrush cleaner once it's reassembled.

I've just moved it all into an ultrasonic cleaner but after that i will get something in there to clean it.

AllSeeingSkink wrote:

If that's clean and your needle is clean, check that the needle tip isn't damaged or bent. It can be hard to see, one of my needles had a bump that was so small I couldn't see it, but I could feel it and when I wiped it with a tissue some of the tissue would catch on the bump and tear. I polished the needle to fix it, but that's not always an option and you may need a new one.

I keep looking at the needle thinking the very tip has a slight bend in it but i cant work out if its my imagination or not because when its in the brush it sitsh flush and pulls back without any resistance.

AllSeeingSkink wrote:

Also are you sure it's not a tip dry problem like we mentioned? Tip dry effects different brushes in different amounts. A brush with a long gradually tapering needle will tip dry much faster than one with a more aggressive taper or a dual taper. It's probably not if you thinned the paint 5:1, but still worth checking.

I dont think its tip dry as even after being dissasembled and cleaned it will spatter like that the moment the trigger is pulled. And honestly the paint coming out in the above example was so thin I'm surprised it even looked black at all.

Johnson & The Juice Crew wrote:
I keep looking at the needle thinking the very tip has a slight bend in it but i cant work out if its my imagination or not because when its in the brush it sitsh flush and pulls back without any resistance.

That could be a problem if it is actually bent. The problem can be so small that you can barely see it by eye, or maybe not at all. For example....

http://communicats.blogspot.com.au/2012/09/why-every-airbrush-artists-should-have.html

AllSeeingSkink wrote:


Though it is odd that you spray at 20PSI with 5:1 thinned Tamiya paint, I'd guess that's too thin for that pressure. What far are you spraying from? Maybe you already mentioned it and I forgot/missed it, but long distance spraying will cause problems.

20psi just happens to be where it is set at at the moment on the guage. The problem still occurs from anywhere between 15 -40 (on my guage) as can be seen in my first post.

Distance varies at the moment as im just spraying on paper to see what happens but with the g35 it makes no difference. I can have the brush resting on the paper or have it at quite some distance the spatter is still the same.

The reason it was 5:1 (or somewhere in that region) was because i started at a 2:1, spray, add thinner, repeat until it got to the point that I could make the assumption that the paint wasnt too thick

After spending all night and most of today sitting in the ultrasonic cleaner in a bath of airbrush cleaner and acrylic thinner it looks like the problem is sorted.

Took it out and wiped it all down and re assembled and spent maybe 30 minutes of just testing on paper and no problems at all. Something must have got stuck or blocked somewhere.

As you've found out, almost all airbrushing problems boil down to 'it's probably dirty', no matter how clean you think it is.

And an ultrasonic cleaner is almost an essential bit of kit.

Glad your problem got resolved.

Looks like you are not mixing enough water and you are having a case of dry tip.

Try adding Vallejo Flow Improver. The stuff isn't dirt cheap but it lasts a while.

Also may want to pick up some Badger Needle Juice. But of these will help.

Also make sure the tip of the needle isn't bent or curved. Hope this helps!

Johnson & The Juice Crew wrote:
After spending all night and most of today sitting in the ultrasonic cleaner in a bath of airbrush cleaner and acrylic thinner it looks like the problem is sorted.

Took it out and wiped it all down and re assembled and spent maybe 30 minutes of just testing on paper and no problems at all. Something must have got stuck or blocked somewhere.

I'm gonna guess it was probably in the nozzle. I don't own one so I'm not sure how good ultrasonic cleaners are for getting that last little bit of paint out of the nozzle, maybe they're sufficient. If not, just figure out a way to mechanically clean it out after each use.