Blotching when airbrushing...

That speckly look can come from paint too thick, or not enough air.  When it's done on purpose, it's called stippling.

Don

Start with paint that looks like/ is as thin as 2% milk. Its a good place to start from. I used to start too thick as well causing this blotchy paint plus it was clogging up the tip, shooting little grains of dried paint as well. Not good...

Try this 2% milk thing and with it, find a pressure setting on your compressor that will work for you and start experimenting from there.

Good luck!

Richard

The picture showed sign of insufficient atomization. As other already said, it is the symptom of paint too thick or pressure too low or combination of both.

When you get a very fine 0.2 mm nozzle airbrush like yours, it is very important to thin the paint enough. When you do thin sufficiently, you will need to paint in misty spray and use multiple passes to get solid coverage. You have to learn to be patient.

If you use Tamiya acrylic paint, start with a 1:1 mixing ratio and increase the thinner if necessary. I found most of the Tamiya acrylic work well in the 1:1 to 2:1 range.

When the paint is properly mixed with thinner, your compressor should work well at the 15-25 psi range. Try different pressure until you get the right setting.

I have a few Badger airbrushes and the 150 (which I think you have). With Tamiya paint I thin it with Tamiya thinners with a 1:1 split and its more than happy at 15psi. I've read some of your posts about what your using as thinners and with all the time it takes you to make a batch of thinners I'd have got a coat of paint on already I think. I agree its not cheap to use Tamiya's but to me ita a whole lot easier

Its easier to add more pain than take it off so do more layers if you need to. Also not sure if anyone has told you this but start with the brush about 2-3 inches from the model and work in one direction per coat, front - back, up - down

Awesome, thanks for the tips guys. I usually spray at around 20 PSI. The hard part for me is the mixing... everything looks like 2% milk in my paint cup - haha. I know it's because I'm very new to this. Do you guys usually mix in your paint cup or in another container then pour in your cup? With the Velocity having a gunmetal-colored cup, sometimes it's hard to see the consistency.

I always mix my paint in a glass bottle (I have a pile of empty Tamiya acrylic paint bottles) so I can see how the paint runs down the side. It also lets me see how transluscent the paint is, another indicator of how much thinner you have in the mix. Keep practicing, it's more black art than science! 

What little tricks do you guys use to make sure it's the right consistency? I am mixing a color in an old glass bottle and running the paint up the side to see how fast it settles back down and how thick a coat it leaves on the side. I just don't know when it's perfect. Grr...

It looks like milk, but I could add 20 more drops of thinner and it'd look the same to me. lol

icer22x

What little tricks do you guys use to make sure it's the right consistency? I am mixing a color in an old glass bottle and running the paint up the side to see how fast it settles back down and how thick a coat it leaves on the side. I just don't know when it's perfect. Grr...

It looks like milk, but I could add 20 more drops of thinner and it'd look the same to me. lol

I hate to tell you this, Icer, but you're doing everything right.  LOL!  That's pretty much how we all get things figured out when it comes to air brushing.  At least that's exactly how I was anyway.  A bit of trial and error before I finally got the "feel" for it.  And it's just that, too.  It's a feel and NOT an exact science. 

One thing I also did was run some water or thinner through the airbrush first.  Partly it was to clean it but mainly it was to get a feel for the effects of pressure, distance held from the model, speed of moving my airbrush left and right, etc.  I sprayed it on some scrap cardboard which usually did a pretty good job at revealing the spray pattern.  Once I got comfy with that, I then "graduated" myself to using paints.

Yes you'll be surprised to see how thin a paint needs to be in order for it to shoot nicely through your airbrush!  And for what it's worth, I typically airbrush around the 18-20 psi range, too.

Keep trying and experimenting and you'll eventually get the hang of it.  One last bit of info, no matter how long you airbrush during your entire airbrushing career, it will never be an exact science!  There's no magic answer or golden key to unlock any secrets.  I went through lots of paint, thinner and cardboard before I finally stopped being scared of the thing.  LOL!

Eric

Thats the hard part my friend... Trial and error. I just try to mimic the settings/ mixtures that worked well for me on a particular model. Doing this several times will give you a " feel" for the paint consistency if you will.

Just looking at paint run down a bottle at this point wont help you one bit unless you know what to look for in it

I'd say just mix stuff until you think it is right, use that and learn from it by trial and error. In this particular case, using the example with the picture you added you have made the paint too thick. So therefore you should mix it up again, use more thinner and see what happens next.

A question on the side though....

Do you use any sort of measuring to mix your paints or do you just mix up paint and thinner as you see fit? It does really help to know exactly what you put in in order to remix it the exact same way next time. I have an aunt into nursing so she gives me a handful of syringes every now and then (without needles ofcourse). Works great everytime and gives very consistently mixed paint every time.

Just a few thoughts...

Richard

Ah! Syringes would be a great idea. I have a bunch of eye droppers right now and I count the drops.

The Velocity's paint cup makes it a little hard to mix the paints IN the cup. I think I am going to start mixing in separate bottles. In the Velocity, I would usually put in thinner first and the first few drops would seep into the main body so I'd end up adding more paint than I needed - I was obviously doing it visually and not using measurements.

I think mixing externally is going to provide me with better results. Thanks for the tips guys!

If the thinner is actually seeping back into the body of the brush then you need to adjust the needle seal. It doesn't take much and you just want to be able to feel that it's there when you slide the needle in by hand. You won't even notice it when you work the trigger. If you need to do that you'll have to disassemble the back end of the brush. Take off the handle, remove the needle, screw out the needle tube and lift out the trigger. Then use a small, fine blade screwdriver to adjust the seal in just a hair. The exploded view in your manual will show what and where it is. It's no big deal. If you need any more info just ask and someone will be happy to help. BUT, if the thinner is just filling the passage at the back and front of the cup you're fine. If you find thinner(or paint) in the body behind the needle seal then you need to adjust it.

As far as mixing your paints, it just takes practice. If you just need a few drops of paint, mixing in the cup on the brush is fine. Don't know how you mix in the cup but I usually just cover the end of the brush and needle and push down on the trigger to blow some air in. The mix in the cup will bubble and mix it all up. Even if you put in the thinner first when you add paint it will go straight to the bottom and into the passage in the front of the brush. Covering the front of the brush and backflushing will push most of it back and mix it.  I still spray a little before actually shooting in on whatever I'm painting. For larger amounts, then mixing in a bottle or jar is the way to go. And don't fret over it. You can always add more thinner or paint. Just keep at it and one day it will all come together for you.

Tony

Another thing to consider is the type of thinner you're using.

Tamiya acrylics can be thinned with a multitude of compatible/semi-compatible thinners which can alter/modify the paint's behaviour.

try mixing ratios and find something that you like. you will know if it's to thick to spray. when you start the paint flow it lags then gets spitting and blobs. 

i usually go 50/50 paint/thinner with tam paints. 

when you stir the paint tap the paint cop with your stir stick and watch is run. if it runs down nicely then it's ready to spray to slow means its still thick and not thinned enough. you want it more like milk then water. 

i had the same problem you did when i was learning. i just sat and tried different things. 

I looked into the needle seal. I shined a light down the body of my airbrush and saw the indentations made for adjustment. I stuck a flat head screw driver down there just to see how tight it was. It was actually a little loose! It took about half a turn to get it GENTLY snug. And I left it at that.

I wonder if it was supposed to be that loose. I definitely didn't mess with it before...

What is the point of that seal? Usually after a couple of sprays when I pull my needle out, there is paint on the needle as far back as the seal. Is it normal for paint to get back that far on the needle? It would make sense that it would since pulling the trigger back draws the needle (and the paint on it) further back into the airbrush... I just don't know if the seal is suppose to prevent that from happening... or if it's suppose to prevent air from escaping back into the brush.

what AB are you using?

How far away are you from the surface when you did this test?

That can also happen from paint drying before hitting the surface which it will do if you are more than a couple of inches away when you spray.

Badger Velocity

make sure your needle tip isn't bent.

Yeh icer, paint will go all the way back to the needle seal. Most other Badger airbrushes use a needle bearing that's inserted from the front of the brush into the passage behind the cup. In that case paint won't flow back quite as far. But when it wears enough to need replacing they recommend sending the brush back to Badger for repair (there's no charge) because it's just a little Teflon sleeve and can be difficult to get in or out. With the type of needle seal used in the Velocity you can adjust and replace it yourself. I believe the original Velocity used a Viton O-ring for a needle seal while the more recent ones use a Teflon ring. Both seat in the front of the screw you adjusted and are compressed against a surface inside the brush when tightened. If it was that loose then it may not have been sealing the needle. Adjust it so that you feel just a slight resistance when you slide the needle in by hand. Just enough so that you can feel that something is there. And I don't think it's unusual to get a brush that needs a little adjustment.

Some older style brushes don't use any type of seal at all other than the clearance between the body of the brush and the needle itself. That's basically a fluid seal. So, if your needle seal is a little on the loose side then plain thinner, alcohol, water or Windex may flow back into the brush a little while mixed paint won't because the paint is thicker.

Tony