Airbrush/Paint issues...

[toofastrobot]

Luckily I haven't started painting my helmet yet, but when testing the new paint, I've found that my airbrush is spraying intermittently. It sprays just fine in a regular spread with no spattering when it does spray, but after about 2 or 3 seconds of spraying only air comes out. Occasionally instead of just spraying air it'll will spray very very fine lines until nothing comes out at all.

I thought it was a paint/thinner ratio issue, I tried 1:1 then 2:1 paint to thinner, both produced the same results. I'm using Humbrol acrylics with humbrol acrylic thinner. I'll try and upload a video to show better what I'm talking about, since googling the problem didn't yield anything useful.
It was spraying just fine with Tamiya paints and since I just dropped about $50 on all these humbrol acrylics I'm really hoping its not the paints themselves. I should also note, when the paint stops spraying, if I release the trigger a little bit, more paint seems to pop out like normal.

 

[toofastrobot]

https://youtu.be/kh0ANBPQWZM

 

[Fettastic]

The first thing I was thinking was your thinner ratio. I also had this problem. Have your tried just spraying water? If you can spray water then you may have small bits of dried paint in your airbrush. Is it gravity fed or siphon fed? Like I said I had this problem too but it turns out it was just my cheap airbrush. I bought a halfway decent one and haven't had any problems since.

 

[toofastrobot]

I've run just water through it too.

It's gravity fed and I've just run the entire airbrush disassembled through an ultrasonic cleaner and the problem persisted. I'm going to try tamiya thinner and see if that's the issue.

 

[Furious]

Ya know I had this problem too. What fixed it for me was I didn't have the head of the brush tight enough. I used the little wrench that came with it and tightened it a little more and it worked.

 

[toofastrobot]

Ya know I had this problem too. What fixed it for me was I didn't have the head of the brush tight enough. I used the little wrench that came with it and tightened it a little more and it worked.

Were you using Humbrol acrylics? I googled a bit more and it looks like Humbrol acrylics are just a nightmare to use. I tried the Tamiya thinner with the humbrol paints and it didn't work, about to run some tamiya and thinner through the brush to see if its the airbrush. Thanks

 

[Furious]

Were you using Humbrol acrylics? I googled a bit more and it looks like Humbrol acrylics are just a nightmare to use. I tried the Tamiya thinner with the humbrol paints and it didn't work, about to run some tamiya and thinner through the brush to see if its the airbrush. Thanks

Hubrol enamel is what I used but when I had that issue I noticed it even with just water.

 

[toofastrobot]

I just ran through the Tamiya acrylics with thinner and it sputtered for a second (I think to get the humbrol out) then sprayed AMAZINGLY. I guess Humbrol acrylics are just not to be used for this!

 

[Major]

Two other things


1 - how new is the paint you're running through it?

2 - when was the last time you changed the needle and other parts in the airbrush?




Sent from my iPhone

 

[Darth Voorhees]

Yea it sounds like there was some dried up acrylic in the brush. If the paints are old like Major was asking, they may have thickened up a bit and may be clumpy. The paints may have been sitting on the shelf a while before you purchased them. I have this issue sometimes with the enamels as well. I usually clean out the brush and put in fresh paint and it works fine.

 

[toofastrobot]

Two other things


1 - how new is the paint you're running through it?

2 - when was the last time you changed the needle and other parts in the airbrush?




Sent from my iPhone

I just got the paints in the mail yesterday. Not sure if they've been sitting for very long.

The parts haven't been changed since I purchased the airbrush, but the humbrol enamels I just finished spraying a couple of months ago went through just fine.

Yea it sounds like there was some dried up acrylic in the brush. If the paints are old like Major was asking, they may have thickened up a bit and may be clumpy. The paints may have been sitting on the shelf a while before you purchased them. I have this issue sometimes with the enamels as well. I usually clean out the brush and put in fresh paint and it works fine.

Like I said though, I had already taken the airbrush apart and ran it through an ultra sonic cleaner after each attempt. I tried humbrol with humbrol thinner, just the humbrol, humbrol with tamiya thinner and each time the humbrol sputtered and then just stopped spraying. I popped the Tamiya in and it sprayed like a dream.

 

[Major]

Sounds to me like you have bad paint then


Sent from my iPhone

 

[toofastrobot]

Yup, just on a whim threw some 78 into my airbrush with a little of the tamiya thinner and had 0 problems. the RLM 76 I've got must just be some problem tins, I'll contact CS and see if I can get a replacement, thanks for helping me troubleshoot, guys!