Remove seal after washing, What the????

Discussion in 'General Electronics Chat' started by spinnaker, Dec 9, 2012.

  1. spinnaker

    Thread Starter AAC Fanatic!

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    I order a small amount of those piezoelectric buzzers from China. They all have stickers on top of them that say "Remove seal after washing" .

    What on earth does this seal mean? Why would I want to wash my buzzer? :)


    [​IMG]
     
  2. #12

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    Perhaps the chinese think you bought a buzzer for your wife. Women always prefer their buzzers to be properly cleaned.:D
     
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  3. MrChips

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    After components are soldered on to the board, they are washed to remove any traces of flux.
     
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  4. #12

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    Thanks Mr Chips. Better than the answer I thought of. I forgot that a lot of modern fluxes can be cleaned off with water.
     
  5. Audioguru

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    Dirty dirty. But I agree.;)
     
  6. Wendy

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    Funny, but I was documenting one for a PCB project I'm doing, as well as drawing it up for Paint CAD.

    You missed an obvious part, the polarity of the buzzer is on that label, not in the plastic. I may scratch it in myself on my part.
     
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  7. #12

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    Another "Thanks". I couldn't see the polarity marking in the photo. It seems to be hiding under the orange wire.
     
  8. spinnaker

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    Yeah I noticed it. Probably more useful for the buzzer itself to be marked but I guess as long as you don't remove it till after install it would be ok.
     
  9. MrChips

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    Doesn't everyone wash the flux off their buzzers after inserting?
     
  10. Wendy

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    Maybe.....
     
  11. Audioguru

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    Um, this thread is going off-topic, talking about "pron".
    I have been using solder with flux in it for many years. The inserter I was born with has never been covered with flux but I always wash it after it has been inserted.
    The "didlow" buzzers used by some women also have never been covered with flux but they also always wash the buzzer after it has been inserted.;)
     
  12. kubeek

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    Boards can also be washed in isopropyl alcohol or other solvents, not necesarily just water.
     
  13. MrChips

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    I hear some people use lemon juice.
     
  14. Audioguru

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    Vinegar is also a mild acid like lemon juice.
     
  15. Wendy

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    Made another interesting discovery about this component. It is not symmetrical. The + lead is both longer (similar to a LED) and the + lead is further from the wall of the package. The + lead is 0.150" from the wall, while the - lead is 0.100" from the wall.

    So you can identify polarity even after the seal is removed. Makes a slight difference in laying the PCB out.
     
  16. dataman19

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    Dec 26, 2009
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    I think you are "all" over looking some thimg....
    Maybe the Chinese wash their components before they solder them?
    Maybe they insert them after washing to be sure there aren't any stray chemmie ( I mean chemicals).
    From what I have seen lately, I tend to believe that they never go through the trouble of properly cleaning boards (which is why I see tons of solder residue traces on boards we get from Chinacon).
    So They would want to remove the seal after washing and before inserting - otherwise they would have a lower reject rate, and everyone knows "Chinese Labor Organizers - "are" pushing for more labor tasks....
    ..
    Dave
    Phoenix, AZ
     
  17. MMcLaren

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    Does anyone have a link for these buzzers, please?

    TIA, Mike
     
  18. MrChips

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  19. spinnaker

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  20. MMcLaren

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