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Higher efficiency in spray painting metal tanks.

  1. Aug 10, 2013 #1
    When a hand spray painting gun is used to paint say metal tanks, about 80% of the paint is lost in the air.

    This not only leads to a wastage of paint, but also the paint partivles settle on other stuff causing paint spots.

    What method can be used to reduce this?

    One is ionizing the tank and the paint with opposite charges.

    Can anyone suggest any other method?

  2. jcsd
  3. Aug 10, 2013 #2

    Simon Bridge

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    That's the common one.
    You can stand closer to the tank and use a weaker spray gun, use a narrower jet from the gun, thicker paint, or just don't use a spray gun ... dip the tanks into a pool of paint or use a brush or a roller.
  4. Aug 11, 2013 #3


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    Avoid a very fine spray. Use the biggest paint droplets practical. Big particles are less influenced by local air movement during flight. Economy is important. It will take more skill to avoid runs, but you will not develop that skill without practice.
  5. Aug 11, 2013 #4
    Thanks a lot guys!

    Dipping is not really an option as we don't have a proper paint shop and the tanks are pretty big.

    But the other things can be tried.
  6. Aug 12, 2013 #5

    Simon Bridge

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    Weird that you lose such a high percentage of the paint to the air.
    That would mean you basically get a big cloud of paint around the tank with most of it falling to the ground or blowing away ... there must be a fine coat of paint over nearby fences, walls, buildings, painters.
    Your face-masks and eye protection (and coveralls, and hat) must end up with as much paint (at least!) as the tanks.

    When kids spray-bomb a wall they just stand close and almost all of it goes onto the graffiti.
  7. Aug 12, 2013 #6
    It isn't an exact calculation, but yeah, a lot of it. There was a problem of yellow spots appearing on cars and monitors on account of the floating paint!

    Like I said, it isn't a proper paint shop so the guys doing the paint aren't really trained and saving isn't a big deal to them.
  8. Aug 12, 2013 #7

    Simon Bridge

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    Rigging canvas screens around the painting area is good too - saves getting yellow spots on stuff.

    If the customer is paying for the paint used separately, and they are happy with the price, then there is not a lot of motivation to save paint. If you could get a decent estimate of how much paint is being wasted, then you could work out the dollar saving - which translates into competitiveness or higher profits by reducing materials costs.
    That could persuade them.

    Saving paint, though, may mean taking longer in the painting ... which increases labor costs and the job may be time-critical. You should explore what the trade-offs actually are.
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