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Compressor and airbrush driving me nuts!


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Ok, so I got a sweet deal (double thinking it now) on this comepressor a Paasche VL, the problems Im having are these.

1- the regulator reads about 40psi when I turn it on (hose and airbrush attached) but when I spray it almost immediately goes down to about 15psi, is this normal or is the regulator jacked up?

2- the paint wont always come out, I noticed that the paint doesnt always come out, and sometime when it does it come outs in irregular patter, like splash, sprinkle, splash, spray. Is it not coming our because the needle is too tight, because the preasure is too low, or do I need to use a bigger tip and thin the s*** out of the paint?

Thanks for reading, if you can I really need the help! I got lots of body work to do! Hahaha

post-14627-0-11022200-1415524292_thumb.j

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if you could plumb the compressor to a receiver (holding tank) at whatever pressure you can, and then regulate the tank to airbrush pressure I think you would see a vast reduction of the air/ no air pressure problem.

have you cleaned the airbrush inner workings? if the unit is clean and working smoothly, your problem might be thick paint. people use the "thin as milk" analogy. there's about a gazillion YouTube airbrushing videos. you'll get the idea after watching 3 or 4.

and everyone else will give you their best solution, so you can pick the one which best suits your method of work.

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Any compressed fluid system (air is a compressible fluid) will give a higher pressure reading on the regulator gauge when there's no fluid flow. The actual working pressure of the system is the reading you get on the gauge when there IS fluid flow (when you trigger the spray gun or airbrush). This holds for big-car 1:1 spray guns as well.

And Joe is right. A larger tank may help. Make sure your airbrush is clean internally and properly assembled, and make sure your paint viscosity is correct. Too-thick paint, a dirty gun, or incorrect assembly can all cause spitting like you describe.

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Unless you have a humungous air leak, the pressure should only drop a few pounds. That doesn't look like a real regulator to me. Can you adjust the pressure before you spray?

15 psi should work for the VL with a fine or medium nozzle if the paint is thin enough. Try spraying plain water. If that works OK, you probably have a paint problem.

Don

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Awesome, I'll clean the airbrush again and try out thining the paint a bit more, and I dont think I can adjust the preasure, when I pull up nothing really happens! But it does have a small square that looks like a nut under the gauge, would this be it?

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Luis, we need pics.

I had similar difficulties when i began airbrushing (this year!).

I thinned the paint 50%, raised the line pressure to 50 lbs., put in a larger tip, and never looked back.

I still keep paint thin, but vary the tip size and line pressure according to the type of paint.

Like, Alclad needs a very small tip, and little pressure. Acrylic for bodies needs a bigger tip (like 0.5mm), and 50 lbs. This works for my air gun, and I'm happy.

Michael

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Ok, here are some pictures, the needles I have and the tips and heads, also on the drawn diagram, I was wondering if there is suppose to be absolutely no gap between the tip and needle? Or just a tiny bit? And the last one is the regulator, piece I was talking about! Thanks!

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post-14627-0-30690500-1415563079_thumb.j

post-14627-0-21926300-1415563092_thumb.j

post-14627-0-93202900-1415563100_thumb.j

Edited by YoungLuis
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If no air flows at the tip, paint doesn't flow either. 5942549_f520.jpg

It's the air flowing that draws the paint out with it.

And this thing appears to be nothing more than a water trap and a pressure gauge. post-14627-0-93202900-1415563100_thumb.j

A regulator will have some kind of adjustment knob on it as well.

AFR2000.JPG

There are also several types of small regulators that attach at the airbrush itself... 21dvvxiJgXL._SY300_.jpg ...but without a gauge, it's hard to get consistent results.

Did it come with any instructions? If not, you probably ought to get some.

Edited by Ace-Garageguy
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thanks for the help guys, really helping me out here! about the needles and tips I actually dont know which go together, I pretty much matched the number "3" head with the needle that had 3 grooves on it, but I don't know what tip goes with the combination, as to the needles being dirty, can I use some sort of wet sanding with thinner? I used water as a test, but than again the same thing happened, with no gap between the needle and tip, water barely comes out, with a gap between the two the water will come out, but air is constantly going through? by the way where can I get that preasure regulator?

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My guess is the dirty needles are a large part of your problem. Wet sanding is a last resort. Try cleaning them with lacquer thinner or acetone. Judging by the needles, the nozzles are also probably filthy. Soak them in acetone or lacquer thinner and swab with cotton on a whittled down toothpick. Hold them up to a light and look in the large end. You should see nothing but shiny metal. Match the nozzle to the head by comparing the size of the openings. Number 1 is the smallest and 5 the largest. Check the needles for burrs on the end and the nozzles for tiny cracks.

Don't let solvent get in the air valve. If you are getting air all the time, the air valve may be stuck open or the tiny o-ring inside damaged. If you take it apart, be careful not to lose the tiny components.

Don

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Ok, so I ran lots of fluids through the airbrush and this is what happened, with the size 1 needle tip and head, I can shoot water no problem, but I think the compressor doesnt make enough preasure because, A- there is no regulator , and B- the O ring that seals the air in the airbrush is missing, gonna buy both today, lets see how this goes!

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do you have access to another source of air? even if you bit the bullet and buy a can of propellant it might be worth isolating the compressor/ airbrush issues. or a fellow artist who has a compressor you can hook up to for a bit and get the airbrush problem sorted, and then work on your compressor thingie.

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My pressure gauge always shows a drop as soon as I start actually sparaying.

I always adjust the pressure by test spaying.

If it has been a long time, I test with water, set the pressure as I spary the water then run Laguer thinner thru everything.

When I am ready to spray the paint, I test spary and adjust the pressure if need be because the paint is thicker than the water, I will spray a few seconds to make sure the piant takes over and has washed out any left over thinner.

Now, if I could just quit jumping when the compressor kicks on and surprises me as I spray...LOL.

Practice practice practice.WATER, THINNER, then PAINT.

Good luck.

Edited by DavidChampagne
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There is only one o-ring in the VL, and that's in the air valve. If it's the old style, it's part number A52. The new style air valve gets part number A53. Have a look at this diagram. There is a packing nut, but that's not likely to be your problem.

If you can spray OK with the #1 nozzle, but not the larger sizes, I think your compressor is tired. The seals do wear out.

A little air leak at airbrush joints is normal. It can usually be stopped with a little bees wax or Chapstick on the threads.

Don

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So this is something I have wondered about since I bought my airbrush: what is the actual air pressure in the circuit both when the airbrush is idle and when it is wide open. normally I set my regulator at 25 psi because that is what I am told is appropriate. I then point and open my airbrush and immediately the pressure drops to 12 psi or so. there are no leaks or anything other than the obvious leak in the airbrush. the question is, which reading is accurate, and further, which reading is what one should pay attention to when receiving advice on the optimum pressure to shoot paint.

I had figured it was the pressure with the system closed (airbrush idle). I guess it makes more sense to use the pressure when it is being used and the circuit is open.

the thing there is that means to run the pressure up around 40 or more psi at idle so it will drop to the correct range when the airbrush is opened. and it also means that when I get advice about optimum pressure I have to wonder where exactly they are measuring the pressure.

by the way, original poster, I think if you soak that stuff in real lacquer thinner (might be difficult to locate in your state) for a couple of days and then clean it with a towel or something, you will see a big difference.

jb

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The right pressure is the one that works the best for you with your airbrush and paint. Some airbrushes need more than others. Bottom fed airbrushes generally need a little more than the gravity fed type. External mix airbrushes usually need more than internal mix. Thicker paint needs more to spray well. Detail work is usually easier with lower pressure than needed for general coverage. It doesn't matter what the gauge says if you adjust pressure to get the output you want. It could range from 8 to 40psi. Once you determine the sweet spot for you, the gauge makes a handy reference, whether you set it with trigger up or trigger down. For my Badger 155 with a 1/4oz. cup and paint thinned the way I like it, somewhere around 15psi works for me.

Don

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I was told by a fellow at work that the only way to actually get the preasure that you see on the gauge on your air brush is to get a tank, but anyways, I got the O ring and that solved everything, the psi it shoots at is normally 35 and 25-30 with the bigger #3 tip, now the question is......why am I getting half inch thick spray areas with the finest tip? Can I make it give me finer lines?

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