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How do you colour metal?

  1. Jul 20, 2010 #1
    How do you colour metal?????

    What are some advantages of corrosion???

    What are the methods one can use to stain mental or change the colour of metal as the Apple company does to create the wide range of different beautiful colours that their iPod's come in???
     
  2. jcsd
  3. Jul 20, 2010 #2

    Pythagorean

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    Re: How do you colour metal?????

    It's ironic you brought up corrosion because when I saw the title of this thread, I instantly thought of how well rust accepted several coats of rust-stop primer, and how well the primer accepted several paints of preferred color as well. I was going to make a joke about it, but is controlled corrosion actually a commercialized technique for painting metal?
     
  4. Jul 20, 2010 #3
    Re: How do you colour metal?????

    You can apply electrochemical corrosion to reduce the thickness of sheet metal for airspace applications.

    Anodising.
     
  5. Jul 20, 2010 #4
    Re: How do you colour metal?????

    I was wondering too if maybe they use some sort of acid like with chroming. Most finished metal though I am pretty sure is coated with something. I'll have to look that up.
     
  6. Jul 20, 2010 #5
    Re: How do you colour metal?????

    yes.... its used as a commercialized technique for painting metal!
     
  7. Jul 20, 2010 #6
    Re: How do you colour metal?????

    yeah, with aluminum, you treat it so that it builds up an oxide layer (essentially ceramic, i think) that is thick and even enough to prevent further corrosion. i think there is just a dye in the chemical solution that becomes impregnated in the oxide layer, but it's been about 10 years since i had to worry with it, so the memory is a bit fuzzy. it's not really a "paint", tho. aluminum anodization is fairly common and you should be able to google a bunch of shops, easily.

    if an actual "painting" technique is what you're after, then there's some interesting stuff like epoxy coating (powder coating), but i don't think it's going to look like a metal surface when done, unless maybe clear.
     
  8. Jul 20, 2010 #7
    Re: How do you colour metal?????

    I've had various parts anodized and powder coated.

    Anodizing is applied using electrolysis whereas with powder coating you electrically charge the part, spray it with a dry powder, then bake it to cure.
     
  9. Jul 20, 2010 #8

    Astronuc

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  10. Sep 9, 2010 #9
    Re: How do you colour metal?????

    This might help.
    Do some research on cold and hot patina. Various techniques have been invented to colorize metal.
     
  11. Sep 9, 2010 #10
    Re: How do you colour metal?????

    Maybe this is off topic but I have anodized metal with Coke a Cola and a car battery hahaha
     
  12. Sep 9, 2010 #11

    Pythagorean

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    Re: How do you colour metal?????

    Then there's alway lead based paints :/
     
  13. Sep 9, 2010 #12
    Re: How do you colour metal?????

    Hammerite, great stuff.
     
  14. Sep 9, 2010 #13

    Gokul43201

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    Re: How do you colour metal?????

    I don't own an iPod, but I thought they had plastic bodies.
     
  15. Sep 9, 2010 #14
  16. Sep 9, 2010 #15
    Re: How do you colour metal?????

    Well, after some thought, i guess the best answer is...

    anyway that you like.
     
  17. Sep 9, 2010 #16
    Re: How do you colour metal?????

    and naw...i got an ipod right here and this baby is metal!
     
  18. Oct 14, 2010 #17
    Re: How do you colour metal?????

    Corrosion gets rid of that pesky metal you leave on structural members after machining, and it's free.

    Apple uses "anodizing." Certain metals, like titanium or aluminum, that can be passivated (that is, grow a hermetic oxide layer) can have the passive layer impregnated with dye. The final product produces a very robust coating where the atoms have grown in register with the underlying metal, so you get very good adhesion and protection of your base metal, and an attractive finish. Passivation is, from certain manners of thinking, a TYPE of corrosion, which may lead to your above question.
     
  19. Oct 25, 2010 #18
    Re: How do you colour metal?????

    Paint, Powdercoat, Anodize, Plating (di and tri chromates etc),

    really a broad question. What do you want to do?

    may i suggest: finishing.com it is a great trouble shooting site.


    good luck with whatever it is you're coloring. You can get some real wild powdercoat and anodized stuff out there.
     
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