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  • Ian M
    Administrator
    • Dec 2008
    • 18269
    • Ian
    • Falster, Denmark

    #16
    Penny, Sounds like you are having fun with your new toy!

    I will try to explain the most common problems with airbrush work and hopefully set a bit of light on a few problems.

    Should this not make any sence at all please PM me your e-mail and I will send you a PDF file I have from Badger.

    The most common problem when airbrushing is findint the ballance between airpresure and the viscosity of the medium you wish to use. The thicker the liquid, the more air will be needed to blow it out of the hole!

    Water like paints; inks will need a low air pressure. Acrylic paints will need more air the thicker its mixed- Thus the comparison to milk. You know that white stuff that runs down the side of a glass but leaves a fine film on said glass. ( were talking orinary milk not none of that low fat chalk water cr#9).

    Its all in the wrist. to get an even coat of paint on a surface, you need to man up and stiffen your wrists and use the most of your arm!!! If you keep your arm still and move your wrist, the airbrush is in effect moving towards and away from the subject we are trying to paint. Not good, you end up with too much paint in the middle, and not enough at the ends. Stiff wrist and move your arm and the airbrush stays the same distance from the subject and thus the paint is hitting it with the same density in the whole lenght of the run. With me so far?. Good then I will carry on.

    The problems with paint. The problems with paint are right in front of you. You just need to know how to read the results of your efforts. I will try to explain.

    [ATTACH]20662.vB[/ATTACH]

    1) Grainy spray. The paint is to thick. thin it gradually or adjust the air pressure UP

    2) The paint is to thin, pools up or runs. Add more paint to the mix and or turn the air DOWN.

    3) If you are painting cotton buds, its a coordination thing; you are stating the paint before you move your hand and stopping the paint after your hand has stopped. Remember, Move, Air on, Paint on - Paint off, air off, stop.

    4) Is a bit tricky as often its not easy to see- You are turning your wrist at the stat and end of the run.

    5)Creapy crawlies! One of my favorites. To much air to much paint to close to the work!

    for finer lines you need very little air and very little paint- you just need to hit the same line several times to get a good coverage.

    6)Splatter, Most often caused by stopping the air befor te paint. This leaves small globs of paint in the guard which can be blow off when you start to paint again. OR if you let the trigger go ad the needle snaps back into the nozzle. Or the nozzle is stating to clog up.

    7)You are painting with your wrist and not keeping the brush parallel to the work.

    8) No picture for this one! If the paint bubbles up in the cup or glass, there could be a blockage in the tip, or the paint regulator and or nozzle are not tight enough.

    9) still on picture, so stop looking for it!!! paint comes out of the nozzle even though you have only turned on the air: There is something in the nozzle that is preventing the needle from closing the hole. Time to clean up.

    Hope that helps with some of the issues that we newbies stumble upon from time to time.

    Ian M

    [ATTACH]27728.IPB[/ATTACH]

    Attached Files
    Group builds

    Bismarck

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    • Guest

      #17
      Ian this is brilliant.

      Prior to your post I had a go at priming a fuselage and it turned out slightly bubbled. I looked for help on you tube and found a video that suggests I may have been spraying from too far away. The video suggests 6" away MAX. This kind of figures as the inside of my spray booth (Cardboard box) is excellently primed. The video says that if you are too far away the paint starts to dry before it hits the model. So Im liking that advice. Im also wondering if I should thin the primer down even more, instead of 1:1 (Well actually 4:4) perhaps try 6:5. If no improvement Ill try 7:5 etc etc

      Im also liking your advice about the wrists. I think Ive been moving my wrist AND my arm, which explains why coverage isnt so good on the ends of the model.

      I cant adjust the paint or air flow as its a cheap old revel starter set AB. Im not going to knock it as the guy in the shop said that its got a wide coverage. Its too wide for weathering but for large coverage (such as 1/48 scale wings and fuselages) its good and it does exactly what he said it does. The problem isnt the AB, its me. He also said that he knows people who use a cheap AB like this for large coverage and a better one (Such as the Iwata one) for fine detail and weathering.

      I shall be sending you e-mail too appreciate any hep I can get. If its ok though, nce you send me the PDF I'll publish it here, no point gathering useful info and keeping it to myself.

      Comment

      • stona
        SMF Supporters
        • Jul 2008
        • 9889

        #18
        That's a great reply from Ian. I'd just like to add that everything is a balancing act. The vital components are paint viscosity and air pressure both of which contribute to the spraying distance. I'd say 6" is a maximum for any airbrush. Your brush has limited options but you'll crack it with a bit of practice. It sounds like you are well on the way already.

        Cheers

        Steve

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